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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 15:07:57 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
tree-wide: fix assorted typos all over the place That is "success", "unknown", "through", "performance", "[re|un]mapping" , "access", "default", "reasonable", "[con]currently", "temperature" , "channel", "[un]used", "application", "example","hierarchy", "therefore" , "[over|under]flow", "contiguous", "threshold", "enough" and others. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-11-14 13:09:05 -02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] kdump: Accessing dump file in linear raw format (/dev/oldmem) Hariprasad Nellitheertha <hari@in.ibm.com> This patch contains the code that enables us to access the previous kernel's memory as /dev/oldmem. Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 14:58:23 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
splice: divorce the splice structure/function definitions from the pipe header We need to move even more stuff into the header so that folks can use the splice_to_pipe() implementation instead of open-coding a lot of pipe knowledge (see relay implementation), so move to our own header file finally. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-06-04 09:59:47 +02:00
Include proper header file for PFN_DOWN() The recent commit (99a10a60ba9bedcf5d70ef81414d3e03816afa3f) to fix up mmap_kmem() broke compiles because it used PFN_DOWN() without including <linux/pfn.h>. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-13 08:42:10 -07:00
drivers/char: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required They will need it called out explicitly in the near future due to a module.h usage cleanup that removes its implicit presence everywhere. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-07-10 12:14:53 -04:00
powerpc: Disable /dev/port interface on systems without an ISA bridge Some power systems do not have legacy ISA devices. So, /dev/port is not a valid interface on these systems. User level tools such as kbdrate is trying to access the device using this interface which is causing the system crash. This patch will fix this issue by not creating this interface on these powerpc systems. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-11 15:18:44 +10:00
fs: move struct kiocb to fs.h struct kiocb now is a generic I/O container, so move it to fs.h. Also do a #include diet for aio.h while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 08:58:50 -08:00
drivers: char: mem: Replace usage of asm include Replaces the use of asm/uaccess.h with linux/uaccess.h. Signed-off-by: Rob Ward <robert.ward114@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-20 18:28:35 +00:00
lockdown: Restrict /dev/{mem,kmem,port} when the kernel is locked down Allowing users to read and write to core kernel memory makes it possible for the kernel to be subverted, avoiding module loading restrictions, and also to steal cryptographic information. Disallow /dev/mem and /dev/kmem from being opened this when the kernel has been locked down to prevent this. Also disallow /dev/port from being opened to prevent raw ioport access and thus DMA from being used to accomplish the same thing. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: x86@kernel.org Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 17:17:41 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Revoke mappings when a driver claims the region Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit 90a545e98126 ("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-21 14:06:17 -07:00
powerpc: Disable /dev/port interface on systems without an ISA bridge Some power systems do not have legacy ISA devices. So, /dev/port is not a valid interface on these systems. User level tools such as kbdrate is trying to access the device using this interface which is causing the system crash. This patch will fix this issue by not creating this interface on these powerpc systems. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-11 15:18:44 +10:00
/dev/mem: introduce size_inside_page() Introduce size_inside_page() to replace duplicate /dev/mem code. Also apply it to /dev/kmem, whose alignment logic was buggy. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:07 -08:00
/dev/mem: make size_inside_page() logic straight Also convert more size_inside_page() users. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Avi Kivity <avi@qumranet.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:09 -08:00
/dev/mem: introduce size_inside_page() Introduce size_inside_page() to replace duplicate /dev/mem code. Also apply it to /dev/kmem, whose alignment logic was buggy. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:07 -08:00
/dev/mem: make size_inside_page() logic straight Also convert more size_inside_page() users. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Avi Kivity <avi@qumranet.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:09 -08:00
/dev/mem: introduce size_inside_page() Introduce size_inside_page() to replace duplicate /dev/mem code. Also apply it to /dev/kmem, whose alignment logic was buggy. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:07 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: use phys_addr_t for physical addresses This patch fixes the /dev/mem driver to use phys_addr_t for physical addresses. This is required on PAE systems, especially those that run entirely out of >4G physical memory space. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12 14:05:58 -04:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: clean up the code Reduce the lines of code and simplify the logic. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 16:42:58 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] /dev/mem: validate mmap requests Add a hook so architectures can validate /dev/mem mmap requests. This is analogous to validation we already perform in the read/write paths. The identity mapping scheme used on ia64 requires that each 16MB or 64MB granule be accessed with exactly one attribute (write-back or uncacheable). This avoids "attribute aliasing", which can cause a machine check. Sample problem scenario: - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K - efi_memmap_init() discards any write-back (WB) memory in the first granule - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0 - hwinfo receives UC mapping (the default, since memmap says "no WB here") - Machine check abort (on chipsets that don't support UC access to WB memory, e.g., sx1000) In the scenario above, the only choices are - Use WB for hwinfo mmap. Can't do this because it causes attribute aliasing with the UC mapping for the VGA MMIO space. - Use UC for hwinfo mmap. Can't do this because the chipset may not support UC for that region. - Disallow the hwinfo mmap with -EINVAL. That's what this patch does. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:13 -08:00
[PATCH] make valid_mmap_phys_addr_range() take a pfn Newer ARMs have a 40 bit physical address space, but mapping physical memory above 4G needs a special page table format which we (currently?) do not use for userspace mappings, so what happens instead is that mapping an address >= 4G will happily discard the upper bits and wrap. There is a valid_mmap_phys_addr_range() arch hook where we could check for >= 4G addresses and deny the mapping, but this hook takes an unsigned long address: static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size); And drivers/char/mem.c:mmap_mem() calls it like this: static int mmap_mem(struct file * file, struct vm_area_struct * vma) { size_t size = vma->vm_end - vma->vm_start; if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size)) So that's not much help either. This patch makes the hook take a pfn instead of a phys address. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 04:45:27 -07:00
[PATCH] /dev/mem: validate mmap requests Add a hook so architectures can validate /dev/mem mmap requests. This is analogous to validation we already perform in the read/write paths. The identity mapping scheme used on ia64 requires that each 16MB or 64MB granule be accessed with exactly one attribute (write-back or uncacheable). This avoids "attribute aliasing", which can cause a machine check. Sample problem scenario: - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K - efi_memmap_init() discards any write-back (WB) memory in the first granule - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0 - hwinfo receives UC mapping (the default, since memmap says "no WB here") - Machine check abort (on chipsets that don't support UC access to WB memory, e.g., sx1000) In the scenario above, the only choices are - Use WB for hwinfo mmap. Can't do this because it causes attribute aliasing with the UC mapping for the VGA MMIO space. - Use UC for hwinfo mmap. Can't do this because the chipset may not support UC for that region. - Disallow the hwinfo mmap with -EINVAL. That's what this patch does. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:13 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
Subject: devmem, x86: fix rename of CONFIG_NONPROMISC_DEVMEM From: Arjan van de Ven <arjan@infradead.org> Date: Sat, 19 Jul 2008 15:47:17 -0700 CONFIG_NONPROMISC_DEVMEM was a rather confusing name - but renaming it to CONFIG_PROMISC_DEVMEM causes problems on architectures that do not support this feature; this patch renames it to CONFIG_STRICT_DEVMEM, so that architectures can opt-in into it. ( the polarity of the option is still the same as it was originally; it needs to be for now to not break architectures that don't have the infastructure yet to support this feature) Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "V.Radhakrishnan" <rk@atr-labs.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> ---
2008-07-18 00:26:59 +02:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: introduce /dev/mem restrictions with a config option This patch introduces a restriction on /dev/mem: Only non-memory can be read or written unless the newly introduced config option is set. The X server needs access to /dev/mem for the PCI space, but it doesn't need access to memory; both the file permissions and SELinux permissions of /dev/mem just make X effectively super-super powerful. With the exception of the BIOS area, there's just no valid app that uses /dev/mem on actual memory. Other popular users of /dev/mem are rootkits and the like. (note: mmap access of memory via /dev/mem was already not allowed since a really long time) People who want to use /dev/mem for kernel debugging can enable the config option. The restrictions of this patch have been in the Fedora and RHEL kernels for at least 4 years without any problems. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:40:47 +02:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: introduce /dev/mem restrictions with a config option This patch introduces a restriction on /dev/mem: Only non-memory can be read or written unless the newly introduced config option is set. The X server needs access to /dev/mem for the PCI space, but it doesn't need access to memory; both the file permissions and SELinux permissions of /dev/mem just make X effectively super-super powerful. With the exception of the BIOS area, there's just no valid app that uses /dev/mem on actual memory. Other popular users of /dev/mem are rootkits and the like. (note: mmap access of memory via /dev/mem was already not allowed since a really long time) People who want to use /dev/mem for kernel debugging can enable the config option. The restrictions of this patch have been in the Fedora and RHEL kernels for at least 4 years without any problems. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:40:47 +02:00
/dev/mem: Bail out upon SIGKILL. syzbot found that a thread can stall for minutes inside read_mem() or write_mem() after that thread was killed by SIGKILL [1]. Reading from iomem areas of /dev/mem can be slow, depending on the hardware. While reading 2GB at one read() is legal, delaying termination of killed thread for minutes is bad. Thus, allow reading/writing /dev/mem and /dev/kmem to be preemptible and killable. [ 1335.912419][T20577] read_mem: sz=4096 count=2134565632 [ 1335.943194][T20577] read_mem: sz=4096 count=2134561536 [ 1335.978280][T20577] read_mem: sz=4096 count=2134557440 [ 1336.011147][T20577] read_mem: sz=4096 count=2134553344 [ 1336.041897][T20577] read_mem: sz=4096 count=2134549248 Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@vger.kernel.org> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com> Link: https://lore.kernel.org/r/1566825205-10703-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-26 22:13:25 +09:00
/dev/mem: make reads and writes interruptible In 8619e5bdeee8 ("/dev/mem: Bail out upon SIGKILL."), /dev/mem became killable, and that commit noted: Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. So now we take the next step in making it "interruptible", by changing fatal_signal_pending() into signal_pending(). Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20220407122638.490660-1-Jason@zx2c4.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-07 14:26:38 +02:00
/dev/mem: Bail out upon SIGKILL. syzbot found that a thread can stall for minutes inside read_mem() or write_mem() after that thread was killed by SIGKILL [1]. Reading from iomem areas of /dev/mem can be slow, depending on the hardware. While reading 2GB at one read() is legal, delaying termination of killed thread for minutes is bad. Thus, allow reading/writing /dev/mem and /dev/kmem to be preemptible and killable. [ 1335.912419][T20577] read_mem: sz=4096 count=2134565632 [ 1335.943194][T20577] read_mem: sz=4096 count=2134561536 [ 1335.978280][T20577] read_mem: sz=4096 count=2134557440 [ 1336.011147][T20577] read_mem: sz=4096 count=2134553344 [ 1336.041897][T20577] read_mem: sz=4096 count=2134549248 Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@vger.kernel.org> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com> Link: https://lore.kernel.org/r/1566825205-10703-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-26 22:13:25 +09:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: use phys_addr_t for physical addresses This patch fixes the /dev/mem driver to use phys_addr_t for physical addresses. This is required on PAE systems, especially those that run entirely out of >4G physical memory space. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12 14:05:58 -04:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Use more consistent data types The xlate_dev_{kmem,mem}_ptr() functions take either a physical address or a kernel virtual address, so data types should be phys_addr_t and void *. They both return a kernel virtual address which is only ever used in calls to copy_{from,to}_user(), so make variables that store it void * rather than char * for consistency. Also only define a weak unxlate_dev_mem_ptr() function if architectures haven't overridden them in the asm/io.h header file. Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-07-28 17:20:33 +02:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: handle out-of-bounds read/write The loff_t type may be wider than phys_addr_t (e.g. on 32-bit systems). Consequently, the file offset may be truncated in the assignment. Currently, /dev/mem wraps around, which may cause applications to read or write incorrect regions of memory by accident. Let's follow POSIX file semantics here and return 0 when reading from and -EFBIG when writing to an offset that cannot be represented by a phys_addr_t. Note that the conditional is optimized out by the compiler if loff_t has the same size as phys_addr_t. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-30 09:48:02 +01:00
[PATCH] EFI, /dev/mem: simplify efi_mem_attribute_range() Pass the size, not a pointer to the size, to efi_mem_attribute_range(). This function validates memory regions for the /dev/mem read/write/mmap paths. The pointer allows arches to reduce the size of the range, but I think that's unnecessary complexity. Simplifying it will let me use efi_mem_attribute_range() to improve the ia64 ioremap() implementation. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Matt Domsch <Matt_Domsch@dell.com> Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com> Cc: "Brown, Len" <len.brown@intel.com> Cc: Andi Kleen <ak@muc.de> Acked-by: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 01:37:05 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: make size_inside_page() logic straight Also convert more size_inside_page() users. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Avi Kivity <avi@qumranet.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:09 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: cleanup unxlate_dev_mem_ptr() calls No behaviour change. [akpm@linux-foundation.org: cleanuplets] [akpm@linux-foundation.org: remove unused `ret'] Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:08 -08:00
/dev/mem: Avoid overwriting "err" in read_mem() Successes in probe_kernel_read() would mask failures in copy_to_user() during read_mem(). Reported-by: Brad Spengler <spender@grsecurity.net> Fixes: 22ec1a2aea73 ("/dev/mem: Add bounce buffer for copy-out") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-27 14:06:14 -07:00
/dev/mem: cleanup unxlate_dev_mem_ptr() calls No behaviour change. [akpm@linux-foundation.org: cleanuplets] [akpm@linux-foundation.org: remove unused `ret'] Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:08 -08:00
/dev/mem: introduce size_inside_page() Introduce size_inside_page() to replace duplicate /dev/mem code. Also apply it to /dev/kmem, whose alignment logic was buggy. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:07 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 09:37:53 +02:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
/dev/mem: Avoid overwriting "err" in read_mem() Successes in probe_kernel_read() would mask failures in copy_to_user() during read_mem(). Reported-by: Brad Spengler <spender@grsecurity.net> Fixes: 22ec1a2aea73 ("/dev/mem: Add bounce buffer for copy-out") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-27 14:06:14 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: PAT avoid aliasing in /dev/mem read/write Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:15 -07:00
/dev/mem: cleanup unxlate_dev_mem_ptr() calls No behaviour change. [akpm@linux-foundation.org: cleanuplets] [akpm@linux-foundation.org: remove unused `ret'] Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:08 -08:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
x86: PAT avoid aliasing in /dev/mem read/write Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:15 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Bail out upon SIGKILL. syzbot found that a thread can stall for minutes inside read_mem() or write_mem() after that thread was killed by SIGKILL [1]. Reading from iomem areas of /dev/mem can be slow, depending on the hardware. While reading 2GB at one read() is legal, delaying termination of killed thread for minutes is bad. Thus, allow reading/writing /dev/mem and /dev/kmem to be preemptible and killable. [ 1335.912419][T20577] read_mem: sz=4096 count=2134565632 [ 1335.943194][T20577] read_mem: sz=4096 count=2134561536 [ 1335.978280][T20577] read_mem: sz=4096 count=2134557440 [ 1336.011147][T20577] read_mem: sz=4096 count=2134553344 [ 1336.041897][T20577] read_mem: sz=4096 count=2134549248 Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@vger.kernel.org> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com> Link: https://lore.kernel.org/r/1566825205-10703-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-26 22:13:25 +09:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Add bounce buffer for copy-out As done for /proc/kcore in commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data") this adds a bounce buffer when reading memory via /dev/mem. This is needed to allow kernel text memory to be read out when built with CONFIG_HARDENED_USERCOPY (which refuses to read out kernel text) and without CONFIG_STRICT_DEVMEM (which would have refused to read any RAM contents at all). Since this build configuration isn't common (most systems with CONFIG_HARDENED_USERCOPY also have CONFIG_STRICT_DEVMEM), this also tries to inform Kconfig about the recommended settings. This patch is modified from Brad Spengler/PaX Team's changes to /dev/mem code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Fixes: f5509cc18daa ("mm: Hardened usercopy") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 13:19:39 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: use phys_addr_t for physical addresses This patch fixes the /dev/mem driver to use phys_addr_t for physical addresses. This is required on PAE systems, especially those that run entirely out of >4G physical memory space. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12 14:05:58 -04:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: handle out-of-bounds read/write The loff_t type may be wider than phys_addr_t (e.g. on 32-bit systems). Consequently, the file offset may be truncated in the assignment. Currently, /dev/mem wraps around, which may cause applications to read or write incorrect regions of memory by accident. Let's follow POSIX file semantics here and return 0 when reading from and -EFBIG when writing to an offset that cannot be represented by a phys_addr_t. Note that the conditional is optimized out by the compiler if loff_t has the same size as phys_addr_t. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-30 09:48:02 +01:00
[PATCH] EFI, /dev/mem: simplify efi_mem_attribute_range() Pass the size, not a pointer to the size, to efi_mem_attribute_range(). This function validates memory regions for the /dev/mem read/write/mmap paths. The pointer allows arches to reduce the size of the range, but I think that's unnecessary complexity. Simplifying it will let me use efi_mem_attribute_range() to improve the ia64 ioremap() implementation. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Matt Domsch <Matt_Domsch@dell.com> Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com> Cc: "Brown, Len" <len.brown@intel.com> Cc: Andi Kleen <ak@muc.de> Acked-by: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 01:37:05 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: make size_inside_page() logic straight Also convert more size_inside_page() users. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Avi Kivity <avi@qumranet.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:09 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
/dev/mem: introduce size_inside_page() Introduce size_inside_page() to replace duplicate /dev/mem code. Also apply it to /dev/kmem, whose alignment logic was buggy. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14 17:58:07 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: PAT avoid aliasing in /dev/mem read/write Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:15 -07:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: PAT avoid aliasing in /dev/mem read/write Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:15 -07:00
mm: Tighten x86 /dev/mem with zeroing reads Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-05 09:39:08 -07:00
x86: PAT avoid aliasing in /dev/mem read/write Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:15 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Bail out upon SIGKILL. syzbot found that a thread can stall for minutes inside read_mem() or write_mem() after that thread was killed by SIGKILL [1]. Reading from iomem areas of /dev/mem can be slow, depending on the hardware. While reading 2GB at one read() is legal, delaying termination of killed thread for minutes is bad. Thus, allow reading/writing /dev/mem and /dev/kmem to be preemptible and killable. [ 1335.912419][T20577] read_mem: sz=4096 count=2134565632 [ 1335.943194][T20577] read_mem: sz=4096 count=2134561536 [ 1335.978280][T20577] read_mem: sz=4096 count=2134557440 [ 1336.011147][T20577] read_mem: sz=4096 count=2134553344 [ 1336.041897][T20577] read_mem: sz=4096 count=2134549248 Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@vger.kernel.org> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com> Link: https://lore.kernel.org/r/1566825205-10703-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-26 22:13:25 +09:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
x86: PAT phys_mem_access_prot_allowed for dev/mem mmap Introduce phys_mem_access_prot_allowed(), which checks whether the mapping is possible, without any conflicts and returns success or failure based on that. phys_mem_access_prot() by itself does not allow failure case. This ability to return error is needed for PAT where we may have aliasing conflicts. x86 setup __HAVE_PHYS_MEM_ACCESS_PROT and move x86 specific code out of /dev/mem into arch specific area. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:20 -07:00
[PATCH] /dev/mem __HAVE_PHYS_MEM_ACCESS_PROT tidy-up Tidy up __HAVE_PHYS_MEM_ACCESS_PROT usage to make mmap_mem() easier to read. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:10 -08:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
frv: hide uncached_access() when pgprot_noncached is not #defined Hide uncached_access() when pgprot_noncached is not #defined. This prevents the following warning: CC drivers/char/mem.o drivers/char/mem.c:229: warning: 'uncached_access' defined but not used Repairs d7d4d849b4e3acc405ec222884936800ffb26d48 ("drivers/char/mem.c: cleanups"). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-06 14:35:08 -07:00
/dev/mem: use phys_addr_t for physical addresses This patch fixes the /dev/mem driver to use phys_addr_t for physical addresses. This is required on PAE systems, especially those that run entirely out of >4G physical memory space. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12 14:05:58 -04:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
frv: hide uncached_access() when pgprot_noncached is not #defined Hide uncached_access() when pgprot_noncached is not #defined. This prevents the following warning: CC drivers/char/mem.o drivers/char/mem.c:229: warning: 'uncached_access' defined but not used Repairs d7d4d849b4e3acc405ec222884936800ffb26d48 ("drivers/char/mem.c: cleanups"). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-06 14:35:08 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
[PATCH] /dev/mem __HAVE_PHYS_MEM_ACCESS_PROT tidy-up Tidy up __HAVE_PHYS_MEM_ACCESS_PROT usage to make mmap_mem() easier to read. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:10 -08:00
/dev/mem: use phys_addr_t for physical addresses This patch fixes the /dev/mem driver to use phys_addr_t for physical addresses. This is required on PAE systems, especially those that run entirely out of >4G physical memory space. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12 14:05:58 -04:00
[PATCH] /dev/mem __HAVE_PHYS_MEM_ACCESS_PROT tidy-up Tidy up __HAVE_PHYS_MEM_ACCESS_PROT usage to make mmap_mem() easier to read. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:10 -08:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
fix bogon in /dev/mem mmap'ing on nommu While digging through my MAP_FIXED changes, I found that rather obvious bug in /dev/mem mmap implementation for nommu archs. get_unmapped_area() is expected to return an address, not a pfn. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-By: David Howells <dhowells@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-16 22:53:16 -07:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
mm: update all remaining mmap_prepare users to use vma_flags_t We will be shortly removing the vm_flags_t field from vm_area_desc so we need to update all mmap_prepare users to only use the dessc->vma_flags field. This patch achieves that and makes all ancillary changes required to make this possible. This lays the groundwork for future work to eliminate the use of vm_flags_t in vm_area_desc altogether and more broadly throughout the kernel. While we're here, we take the opportunity to replace VM_REMAP_FLAGS with VMA_REMAP_FLAGS, the vma_flags_t equivalent. No functional changes intended. Link: https://lkml.kernel.org/r/fb1f55323799f09fe6a36865b31550c9ec67c225.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Damien Le Moal <dlemoal@kernel.org> [zonefs] Acked-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Pedro Falcato <pfalcato@suse.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:18 +00:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
const: mark struct vm_struct_operations * mark struct vm_area_struct::vm_ops as const * mark vm_ops in AGP code But leave TTM code alone, something is fishy there with global vm_ops being used. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 22:29:37 +04:00
use generic_access_phys for /dev/mem mappings Use generic_access_phys as the access_process_vm access function for /dev/mem mappings. This makes it possible to debug the X server. [akpm@linux-foundation.org: repair all the architectures which broke] Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Benjamin Herrensmidt <benh@kernel.crashing.org> Cc: Dave Airlie <airlied@linux.ie> Cc: Hugh Dickins <hugh@veritas.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-23 21:27:07 -07:00
x86: PAT use reserve free memtype in mmap of /dev/mem Use reserve_memtype and free_memtype wrappers for /dev/mem mmaps. The memtype is slightly complicated here, given that we have to support existing X mappings. We fallback on UC_MINUS for that. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:21 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
drivers: char: mem: Check for address space wraparound with mmap() /dev/mem currently allows mmap() mappings that wrap around the end of the physical address space, which should probably be illegal. It circumvents the existing STRICT_DEVMEM permission check because the loop immediately terminates (as the start address is already higher than the end address). On the x86_64 architecture it will then cause a panic (from the BUG(start >= end) in arch/x86/mm/pat.c:reserve_memtype()). This patch adds an explicit check to make sure offset + size will not wrap around in the physical address type. Signed-off-by: Julius Werner <jwerner@chromium.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-12 14:42:58 -07:00
x86/mm: Limit mmap() of /dev/mem to valid physical addresses One thing /dev/mem access APIs should verify is that there's no way that excessively large pfn's can leak into the high bits of the page table entry. In particular, if people can use "very large physical page addresses" through /dev/mem to set the bits past bit 58 - SOFTW4 and permission key bits and NX bit, that could *really* confuse the kernel. We had an earlier attempt: ce56a86e2ade ("x86/mm: Limit mmap() of /dev/mem to valid physical addresses") ... which turned out to be too restrictive (breaking mem=... bootups for example) and had to be reverted in: 90edaac62729 ("Revert "x86/mm: Limit mmap() of /dev/mem to valid physical addresses"") This v2 attempt modifies the original patch and makes sure that mmap(/dev/mem) limits the pfns so that it at least fits in the actual pteval_t architecturally: - Make sure mmap_mem() actually validates that the offset fits in phys_addr_t ( This may be indirectly true due to some other check, but it's not entirely obvious. ) - Change valid_mmap_phys_addr_range() to just use phys_addr_valid() on the top byte ( Top byte is sufficient, because mmap_mem() has already checked that it cannot wrap. ) - Add a few comments about what the valid_phys_addr_range() vs. valid_mmap_phys_addr_range() difference is. Signed-off-by: Craig Bergstrom <craigb@google.com> [ Fixed the checks and added comments. ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [ Collected the discussion and patches into a commit. ] Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sander Eikelenboom <linux@eikelenboom.it> Cc: Sean Young <sean@mess.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/CA+55aFyEcOMb657vWSmrM13OxmHxC-XxeBmNis=DwVvpJUOogQ@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-15 15:29:51 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
x86/mm: Limit mmap() of /dev/mem to valid physical addresses One thing /dev/mem access APIs should verify is that there's no way that excessively large pfn's can leak into the high bits of the page table entry. In particular, if people can use "very large physical page addresses" through /dev/mem to set the bits past bit 58 - SOFTW4 and permission key bits and NX bit, that could *really* confuse the kernel. We had an earlier attempt: ce56a86e2ade ("x86/mm: Limit mmap() of /dev/mem to valid physical addresses") ... which turned out to be too restrictive (breaking mem=... bootups for example) and had to be reverted in: 90edaac62729 ("Revert "x86/mm: Limit mmap() of /dev/mem to valid physical addresses"") This v2 attempt modifies the original patch and makes sure that mmap(/dev/mem) limits the pfns so that it at least fits in the actual pteval_t architecturally: - Make sure mmap_mem() actually validates that the offset fits in phys_addr_t ( This may be indirectly true due to some other check, but it's not entirely obvious. ) - Change valid_mmap_phys_addr_range() to just use phys_addr_valid() on the top byte ( Top byte is sufficient, because mmap_mem() has already checked that it cannot wrap. ) - Add a few comments about what the valid_phys_addr_range() vs. valid_mmap_phys_addr_range() difference is. Signed-off-by: Craig Bergstrom <craigb@google.com> [ Fixed the checks and added comments. ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [ Collected the discussion and patches into a commit. ] Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hans Verkuil <hans.verkuil@cisco.com> Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sander Eikelenboom <linux@eikelenboom.it> Cc: Sean Young <sean@mess.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/CA+55aFyEcOMb657vWSmrM13OxmHxC-XxeBmNis=DwVvpJUOogQ@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-15 15:29:51 -07:00
drivers: char: mem: Check for address space wraparound with mmap() /dev/mem currently allows mmap() mappings that wrap around the end of the physical address space, which should probably be illegal. It circumvents the existing STRICT_DEVMEM permission check because the loop immediately terminates (as the start address is already higher than the end address). On the x86_64 architecture it will then cause a panic (from the BUG(start >= end) in arch/x86/mm/pat.c:reserve_memtype()). This patch adds an explicit check to make sure offset + size will not wrap around in the physical address type. Signed-off-by: Julius Werner <jwerner@chromium.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-12 14:42:58 -07:00
drivers: char: mem: Fix wraparound check to allow mappings up to the end A recent fix to /dev/mem prevents mappings from wrapping around the end of physical address space. However, the check was written in a way that also prevents a mapping reaching just up to the end of physical address space, which may be a valid use case (especially on 32-bit systems). This patch fixes it by checking the last mapped address (instead of the first address behind that) for overflow. Fixes: b299cde245 ("drivers: char: mem: Check for address space wraparound with mmap()") Cc: <stable@vger.kernel.org> Reported-by: Nico Huber <nico.h@gmx.de> Signed-off-by: Julius Werner <jwerner@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-02 15:36:39 -07:00
drivers: char: mem: Check for address space wraparound with mmap() /dev/mem currently allows mmap() mappings that wrap around the end of the physical address space, which should probably be illegal. It circumvents the existing STRICT_DEVMEM permission check because the loop immediately terminates (as the start address is already higher than the end address). On the x86_64 architecture it will then cause a panic (from the BUG(start >= end) in arch/x86/mm/pat.c:reserve_memtype()). This patch adds an explicit check to make sure offset + size will not wrap around in the physical address type. Signed-off-by: Julius Werner <jwerner@chromium.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-12 14:42:58 -07:00
[PATCH] /dev/mem: validate mmap requests Add a hook so architectures can validate /dev/mem mmap requests. This is analogous to validation we already perform in the read/write paths. The identity mapping scheme used on ia64 requires that each 16MB or 64MB granule be accessed with exactly one attribute (write-back or uncacheable). This avoids "attribute aliasing", which can cause a machine check. Sample problem scenario: - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K - efi_memmap_init() discards any write-back (WB) memory in the first granule - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0 - hwinfo receives UC mapping (the default, since memmap says "no WB here") - Machine check abort (on chipsets that don't support UC access to WB memory, e.g., sx1000) In the scenario above, the only choices are - Use WB for hwinfo mmap. Can't do this because it causes attribute aliasing with the UC mapping for the VGA MMIO space. - Use UC for hwinfo mmap. Can't do this because the chipset may not support UC for that region. - Disallow the hwinfo mmap with -EINVAL. That's what this patch does. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:13 -08:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
[PATCH] /dev/mem: validate mmap requests Add a hook so architectures can validate /dev/mem mmap requests. This is analogous to validation we already perform in the read/write paths. The identity mapping scheme used on ia64 requires that each 16MB or 64MB granule be accessed with exactly one attribute (write-back or uncacheable). This avoids "attribute aliasing", which can cause a machine check. Sample problem scenario: - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K - efi_memmap_init() discards any write-back (WB) memory in the first granule - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0 - hwinfo receives UC mapping (the default, since memmap says "no WB here") - Machine check abort (on chipsets that don't support UC access to WB memory, e.g., sx1000) In the scenario above, the only choices are - Use WB for hwinfo mmap. Can't do this because it causes attribute aliasing with the UC mapping for the VGA MMIO space. - Use UC for hwinfo mmap. Can't do this because the chipset may not support UC for that region. - Disallow the hwinfo mmap with -EINVAL. That's what this patch does. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 01:04:13 -08:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
devmem: add range_is_allowed() check to mmap of /dev/mem Earlier patch that introduced CONFIG_NONPROMISC_DEVMEM, did the range_is_allowed() check only for read and write. Add range_is_allowed() check to mmap of /dev/mem as well. Changes the paramaters of range_is_allowed() to pfn and size to handle more than 32 bits of physical address on 32 bit arch cleanly. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-06 23:01:47 -08:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
x86: PAT phys_mem_access_prot_allowed for dev/mem mmap Introduce phys_mem_access_prot_allowed(), which checks whether the mapping is possible, without any conflicts and returns success or failure based on that. phys_mem_access_prot() by itself does not allow failure case. This ability to return error is needed for PAT where we may have aliasing conflicts. x86 setup __HAVE_PHYS_MEM_ACCESS_PROT and move x86 specific code out of /dev/mem into arch specific area. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:20 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
mm: update all remaining mmap_prepare users to use vma_flags_t We will be shortly removing the vm_flags_t field from vm_area_desc so we need to update all mmap_prepare users to only use the dessc->vma_flags field. This patch achieves that and makes all ancillary changes required to make this possible. This lays the groundwork for future work to eliminate the use of vm_flags_t in vm_area_desc altogether and more broadly throughout the kernel. While we're here, we take the opportunity to replace VM_REMAP_FLAGS with VMA_REMAP_FLAGS, the vma_flags_t equivalent. No functional changes intended. Link: https://lkml.kernel.org/r/fb1f55323799f09fe6a36865b31550c9ec67c225.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Damien Le Moal <dlemoal@kernel.org> [zonefs] Acked-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Pedro Falcato <pfalcato@suse.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:18 +00:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
mm/vma: eliminate mmap_action->error_hook, introduce error_override Rather than providing a hook, simplify things by providing the ability to override mmap action errors. This allows us to more carefully validate the value provided and thus ensure only a valid error code is specified, and simplifies the interface. This way, we eliminate all hooks but mmap_prepare and allow only mmap actions to be specified (which core mm controls). This significantly improves robustness and eliminates any unnecessary code duplication in driver mmap hooks. We also update the /dev/mem logic (the only user) to use mmap_action->error_override instead. Link: https://lore.kernel.org/55d13f7d016b827c459946d46a56105635be111c.1780397980.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jann Horn <jannh@google.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02 12:06:27 +01:00
x86: PAT use reserve free memtype in mmap of /dev/mem Use reserve_memtype and free_memtype wrappers for /dev/mem mmaps. The memtype is slightly complicated here, given that we have to support existing X mappings. We fallback on UC_MINUS for that. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-18 17:00:21 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/port: don't compile file operations without CONFIG_DEVPORT In the future inb() and friends will not be available when compiling with CONFIG_HAS_IOPORT=n so we must only try to access them here if CONFIG_DEVPORT is set which depends on HAS_IOPORT. Co-developed-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Link: https://lore.kernel.org/r/20240404114917.3627747-2-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-04 13:49:17 +02:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
Remove 'type' argument from access_ok() function Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: fix small coding style issues This patch fixes four foo * bar errors, and one trailing whitespace complaint from checkpatch.pl Signed-off-by: Hans Grob <H.Grob@physik.uni-muenchen.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-06 11:37:20 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
Remove 'type' argument from access_ok() function Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers: char: mem: Fix Missing blank line issues Fixes "Missing a blank line after declarations" reported by checkpatch. This patch introduces no functional changes. Signed-off-by: Rob Ward <robert.ward114@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-20 18:28:36 +00:00
[PATCH] adjust /dev/{kmem,mem,port} write handlers The /dev/mem and /dev/kmem write handlers weren't fully POSIX compliant in that they wouldn't always force the file pointer to be updated when returning success status. The /dev/port write handler was inconsistent with the /dev/mem and /dev/kmem handlers in that when encountering a -EFAULT condition after already having written a number of items it would return -EFAULT rather than the number of bytes written. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 03:07:31 -08:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
[PATCH] adjust /dev/{kmem,mem,port} write handlers The /dev/mem and /dev/kmem write handlers weren't fully POSIX compliant in that they wouldn't always force the file pointer to be updated when returning success status. The /dev/port write handler was inconsistent with the /dev/mem and /dev/kmem handlers in that when encountering a -EFAULT condition after already having written a number of items it would return -EFAULT rather than the number of bytes written. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 03:07:31 -08:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/port: don't compile file operations without CONFIG_DEVPORT In the future inb() and friends will not be available when compiling with CONFIG_HAS_IOPORT=n so we must only try to access them here if CONFIG_DEVPORT is set which depends on HAS_IOPORT. Co-developed-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Link: https://lore.kernel.org/r/20240404114917.3627747-2-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-04 13:49:17 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
[PATCH] splice: add ->splice_write support for /dev/null Useful for testing. Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-26 14:40:08 +02:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
[PATCH] splice: add ->splice_write support for /dev/null Useful for testing. Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-26 14:40:08 +02:00
/dev/null: add IORING_OP_URING_CMD support This patch adds support for the io_uring command pass through, aka IORING_OP_URING_CMD, to the /dev/null driver. As with all of the /dev/null functionality, the implementation is just a simple sink where commands go to die, but it should be useful for developers who need a simple IORING_OP_URING_CMD test device that doesn't require any special hardware. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-08-19 16:20:33 -04:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
drivers: char: mem: Fix Missing blank line issues Fixes "Missing a blank line after declarations" reported by checkpatch. This patch introduces no functional changes. Signed-off-by: Rob Ward <robert.ward114@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-20 18:28:36 +00:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
/dev/mem: nowait zero/null ops Make read_iter_zero() to honor IOCB_NOWAIT, so /dev/zero can be advertised as FMODE_NOWAIT. It's useful for io_uring, which needs it to apply certain optimisations when doing I/O against the device. Set FMODE_NOWAIT for /dev/null as well, it never waits and therefore trivially meets the criteria. Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/f11090f97ddc2b2ce49ea1211258658ddfbc5563.1631127867.git.asml.silence@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-08 20:10:38 +01:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
char: add aio_{read,write} to /dev/{null,zero} These are handy for measuring the cost of the aio infrastructure with operations that do very little and complete immediately. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:18:27 -07:00
/dev/zero: also implement ->read Christophe reported a major speedup due to avoiding the iov_iter overhead, so just add this trivial function. Note that /dev/zero already implements both an iter and non-iter writes so this just makes it more symmetric. Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200903155922.1111551-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 17:59:22 +02:00
/dev/zero: fixups for ->read Reported the cleared bytes in case of a partial clear_user instead of -EFAULT, and remove a pointless conditional, as cleared must be non-zero by the time we hit the signal_pending check. Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200907082700.2057137-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-07 10:27:00 +02:00
/dev/zero: also implement ->read Christophe reported a major speedup due to avoiding the iov_iter overhead, so just add this trivial function. Note that /dev/zero already implements both an iter and non-iter writes so this just makes it more symmetric. Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200903155922.1111551-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 17:59:22 +02:00
/dev/zero: fixups for ->read Reported the cleared bytes in case of a partial clear_user instead of -EFAULT, and remove a pointless conditional, as cleared must be non-zero by the time we hit the signal_pending check. Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200907082700.2057137-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-07 10:27:00 +02:00
/dev/zero: also implement ->read Christophe reported a major speedup due to avoiding the iov_iter overhead, so just add this trivial function. Note that /dev/zero already implements both an iter and non-iter writes so this just makes it more symmetric. Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200903155922.1111551-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 17:59:22 +02:00
/dev/zero: fixups for ->read Reported the cleared bytes in case of a partial clear_user instead of -EFAULT, and remove a pointless conditional, as cleared must be non-zero by the time we hit the signal_pending check. Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200907082700.2057137-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-07 10:27:00 +02:00
/dev/zero: also implement ->read Christophe reported a major speedup due to avoiding the iov_iter overhead, so just add this trivial function. Note that /dev/zero already implements both an iter and non-iter writes so this just makes it more symmetric. Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200903155922.1111551-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 17:59:22 +02:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
remove ZERO_PAGE The commit b5810039a54e5babf428e9a1e89fc1940fabff11 contains the note A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and thus mapcounted and count towards shared rss). These writes to the struct page could cause excessive cacheline bouncing on big systems. There are a number of ways this could be addressed if it is an issue. And indeed this cacheline bouncing has shown up on large SGI systems. There was a situation where an Altix system was essentially livelocked tearing down ZERO_PAGE pagetables when an HPC app aborted during startup. This situation can be avoided in userspace, but it does highlight the potential scalability problem with refcounting ZERO_PAGE, and corner cases where it can really hurt (we don't want the system to livelock!). There are several broad ways to fix this problem: 1. add back some special casing to avoid refcounting ZERO_PAGE 2. per-node or per-cpu ZERO_PAGES 3. remove the ZERO_PAGE completely I will argue for 3. The others should also fix the problem, but they result in more complex code than does 3, with little or no real benefit that I can see. Why? Inserting a ZERO_PAGE for anonymous read faults appears to be a false optimisation: if an application is performance critical, it would not be doing many read faults of new memory, or at least it could be expected to write to that memory soon afterwards. If cache or memory use is critical, it should not be working with a significant number of ZERO_PAGEs anyway (a more compact representation of zeroes should be used). As a sanity check -- mesuring on my desktop system, there are never many mappings to the ZERO_PAGE (eg. 2 or 3), thus memory usage here should not increase much without it. When running a make -j4 kernel compile on my dual core system, there are about 1,000 mappings to the ZERO_PAGE created per second, but about 1,000 ZERO_PAGE COW faults per second (less than 1 ZERO_PAGE mapping per second is torn down without being COWed). So removing ZERO_PAGE will save 1,000 page faults per second when running kbuild, while keeping it only saves less than 1 page clearing operation per second. 1 page clear is cheaper than a thousand faults, presumably, so there isn't an obvious loss. Neither the logical argument nor these basic tests give a guarantee of no regressions. However, this is a reasonable opportunity to try to remove the ZERO_PAGE from the pagefault path. If it is found to cause regressions, we can reintroduce it and just avoid refcounting it. The /dev/zero ZERO_PAGE usage and TLB tricks also get nuked. I don't see much use to them except on benchmarks. All other users of ZERO_PAGE are converted just to use ZERO_PAGE(0) for simplicity. We can look at replacing them all and maybe ripping out ZERO_PAGE completely when we are more satisfied with this solution. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus "snif" Torvalds <torvalds@linux-foundation.org>
2007-10-16 01:24:40 -07:00
drivers/char/mem: mmap readonly MAP_SHARED-/dev/zero correctly Rather surprisingly, opening /dev/zero read-only then mmap()'ing it MAP_SHARED gets you true anonymous memory (albeit in a VMA with non-NULL vma->vm_file). This is a by-product of MAP_PRIVATE-/dev/zero being how anonymous memory was mapped in Linux's distant past. It happens because mmap_zero_prepare() gates on VMA_SHARED_BIT and when mapping a read-only file MAP_SHARED, do_mmap() clears VMA_SHARED_BIT and VMA_MAYWRITE_BIT. The gating is incorrect - the (poorly named) VMA_MAYSHARE_BIT flag exists explicitly to tell you if something was originally mapped MAP_SHARED. So the fix is simple - gate on this instead. This isn't exactly a common use case, but it's unexpected behaviour which now causes an assert if CONFIG_DEBUG_VM is set. While this bug has existed since the dawn of time for linux (or at least since 2.6.12), it hasn't caused issues in the past, so while it's incorrect behaviour, it doesn't seem necessary to backport that far. The mapping is now accounted at mmap time and can fail with -ENOMEM under strict overcommit, and read faults allocate folios. However this is normal behaviour for a read-only shmem mapping. Commit 93c0c8dc87f6 ("mm/rmap: use anon pgoff to track MAP_PRIVATE file-backed anon folios") is the first patch at which the debug assert fires, so target that instead. Link: https://lore.kernel.org/20260924-fix-dev-zero-readonly-shared-v1-1-153c2111e323@kernel.org Fixes: 93c0c8dc87f6 ("mm/rmap: use anon pgoff to track MAP_PRIVATE file-backed anon folios") Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reported-by: <syzbot+c181d3198e98f8aef8b9@syzkaller.appspotmail.com> Closes: https://lore.kernel.org/linux-mm/6ab4ae75.80e1c6cc.1e8e5f.000d.GAE@google.com/ Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Lance Yang <lance.yang@linux.dev>
2026-09-24 15:48:24 +01:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
drivers/char/mem: eliminate unnecessary use of success_hook Patch series "remove mmap_action success, error hooks", v3. The mmap_action->success_hook was a strange beast added to enable code which appeared to absolutely require access to a VMA pointer to work correctly. Primarily this was for hugetlb, however a different approach will be taken there, as clearly more work is required to figure out a sensible way of converting hugetlb to use mmap_prepare. The other user was the memory char driver, specifically /dev/zero which has the unusual property of explicitly setting file-backed VMAs anonymous. Providing the success hook was always foolish, as it allowed drivers a way to workaround the restriction that they should not access a pointer to a not-yet-correctly-initialised VMA - which defeats the purpose of the mmap_prepare work. We can achieve the same thing in memory char driver without needing the success hook, so this series removes that, then removes the success hook altogether. The error hook is also unnecessary - the motivation for this was for functions which need to override the error code when performing an mmap action in order to avoid breaking userspace. We can achieve this by just providing a field for the error code. Doing this means we don't have to worry about the hook doing anything odd. We also add a check to ensure the error code is in fact valid. Again the memory char driver is the only current user of this, so this series updates it to use that. After this change mmap_action has no custom hooks at all, which seems rather more cromulent than before. This patch (of 3): /dev/zero, uniquely, marks memory mapped there as anonymous. This is currently achieved using the mmap_action->success_hook. However this hook circumvents the abstraction of VMA initialisation so it's preferable to do things a different way. To achieve this, this patch firstly defaults the VMA descriptor's vm_ops field to the dummy VMA operations, which is what file-backed VMAs default this field to. That way, we can detect whether a driver sets this field to NULL in order to mark it anonymous. We then introduce vma_desc_set_anonymous() to do this explicitly, and invoke it in mmap_zero_prepare(). This way, any driver which does not explicitly set desc->vm_ops, retains the dummy vm_ops as they would previously. We also update set_vma_user_defined_fields() to make clear that we are either setting vma->vm_ops to what is provided by the driver (or defaulting to dummy_vm_ops if not set), or setting the VMA anonymous. This lays the groundwork for removing the success hook. Link: https://lore.kernel.org/cover.1780397980.git.ljs@kernel.org Link: https://lore.kernel.org/010579cca6787cf7bb057ab1f7228978b10601c8.1780397980.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jann Horn <jannh@google.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02 12:06:25 +01:00
remove ZERO_PAGE The commit b5810039a54e5babf428e9a1e89fc1940fabff11 contains the note A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and thus mapcounted and count towards shared rss). These writes to the struct page could cause excessive cacheline bouncing on big systems. There are a number of ways this could be addressed if it is an issue. And indeed this cacheline bouncing has shown up on large SGI systems. There was a situation where an Altix system was essentially livelocked tearing down ZERO_PAGE pagetables when an HPC app aborted during startup. This situation can be avoided in userspace, but it does highlight the potential scalability problem with refcounting ZERO_PAGE, and corner cases where it can really hurt (we don't want the system to livelock!). There are several broad ways to fix this problem: 1. add back some special casing to avoid refcounting ZERO_PAGE 2. per-node or per-cpu ZERO_PAGES 3. remove the ZERO_PAGE completely I will argue for 3. The others should also fix the problem, but they result in more complex code than does 3, with little or no real benefit that I can see. Why? Inserting a ZERO_PAGE for anonymous read faults appears to be a false optimisation: if an application is performance critical, it would not be doing many read faults of new memory, or at least it could be expected to write to that memory soon afterwards. If cache or memory use is critical, it should not be working with a significant number of ZERO_PAGEs anyway (a more compact representation of zeroes should be used). As a sanity check -- mesuring on my desktop system, there are never many mappings to the ZERO_PAGE (eg. 2 or 3), thus memory usage here should not increase much without it. When running a make -j4 kernel compile on my dual core system, there are about 1,000 mappings to the ZERO_PAGE created per second, but about 1,000 ZERO_PAGE COW faults per second (less than 1 ZERO_PAGE mapping per second is torn down without being COWed). So removing ZERO_PAGE will save 1,000 page faults per second when running kbuild, while keeping it only saves less than 1 page clearing operation per second. 1 page clear is cheaper than a thousand faults, presumably, so there isn't an obvious loss. Neither the logical argument nor these basic tests give a guarantee of no regressions. However, this is a reasonable opportunity to try to remove the ZERO_PAGE from the pagefault path. If it is found to cause regressions, we can reintroduce it and just avoid refcounting it. The /dev/zero ZERO_PAGE usage and TLB tricks also get nuked. I don't see much use to them except on benchmarks. All other users of ZERO_PAGE are converted just to use ZERO_PAGE(0) for simplicity. We can look at replacing them all and maybe ripping out ZERO_PAGE completely when we are more satisfied with this solution. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus "snif" Torvalds <torvalds@linux-foundation.org>
2007-10-16 01:24:40 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/zero: try to align PMD_SIZE for private mapping Attempt to map aligned to huge page size for private mapping which could achieve performance gains, the mprot_tw4m in libMicro average execution time on arm64: - Test case: mprot_tw4m - Before the patch: 22 us - After the patch: 17 us If THP config is not set, we fall back to system page size mappings. Link: https://lkml.kernel.org/r/20250731122305.2669090-1-zhangqilong3@huawei.com Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-31 20:23:05 +08:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
/dev/zero: try to align PMD_SIZE for private mapping Attempt to map aligned to huge page size for private mapping which could achieve performance gains, the mprot_tw4m in libMicro average execution time on arm64: - Test case: mprot_tw4m - Before the patch: 22 us - After the patch: 17 us If THP config is not set, we fall back to system page size mappings. Link: https://lkml.kernel.org/r/20250731122305.2669090-1-zhangqilong3@huawei.com Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-31 20:23:05 +08:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
mm: consistently use current->mm in mm_get_unmapped_area() mm_get_unmapped_area() is a wrapper around arch_get_unmapped_area() / arch_get_unmapped_area_topdown(), both of which search current->mm for some free space. Neither take an mm_struct - they implicitly operate on current->mm. But the wrapper takes an mm_struct and uses it to decide whether to search bottom up or top down. All callers pass in current->mm for this, so everything is working consistently. But it feels like an accident waiting to happen; eventually someone will call that function with a different mm, expecting to find free space in it, but what gets returned is free space in the current mm. So let's simplify by removing the parameter and have the wrapper use current->mm to decide which end to start at. Now everything is consistent and self-documenting. Link: https://lkml.kernel.org/r/20251003155306.2147572-1-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-03 16:53:04 +01:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
/dev/zero: try to align PMD_SIZE for private mapping Attempt to map aligned to huge page size for private mapping which could achieve performance gains, the mprot_tw4m in libMicro average execution time on arm64: - Test case: mprot_tw4m - Before the patch: 22 us - After the patch: 17 us If THP config is not set, we fall back to system page size mappings. Link: https://lkml.kernel.org/r/20250731122305.2669090-1-zhangqilong3@huawei.com Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-31 20:23:05 +08:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
treewide: Use fallthrough pseudo-keyword Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
drivers: char: mem: fix IS_ERROR_VALUE usage IS_ERR_VALUE macro should be used only with unsigned long type. Specifically it works incorrectly with longer types. The patch follows conclusion from discussion on LKML [1][2]. [1]: http://permalink.gmane.org/gmane.linux.kernel/2120927 [2]: http://permalink.gmane.org/gmane.linux.kernel/2150581 Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15 15:35:21 +01:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: fix small coding style issues This patch fixes four foo * bar errors, and one trailing whitespace complaint from checkpatch.pl Signed-off-by: Hans Grob <H.Grob@physik.uni-muenchen.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-06 11:37:20 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: Revoke mappings when a driver claims the region Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit 90a545e98126 ("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-21 14:06:17 -07:00
lockdown: Restrict /dev/{mem,kmem,port} when the kernel is locked down Allowing users to read and write to core kernel memory makes it possible for the kernel to be subverted, avoiding module loading restrictions, and also to steal cryptographic information. Disallow /dev/mem and /dev/kmem from being opened this when the kernel has been locked down to prevent this. Also disallow /dev/port from being opened to prevent raw ioport access and thus DMA from being used to accomplish the same thing. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: x86@kernel.org Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 17:17:41 -07:00
/dev/mem: Revoke mappings when a driver claims the region Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit 90a545e98126 ("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-21 14:06:17 -07:00
resource: Move devmem revoke code to resource framework We want all iomem mmaps to consistently revoke ptes when the kernel takes over and CONFIG_IO_STRICT_DEVMEM is enabled. This includes the pci bar mmaps available through procfs and sysfs, which currently do not revoke mappings. To prepare for this, move the code from the /dev/kmem driver to kernel/resource.c. During review Jason spotted that barriers are used somewhat inconsistently. Fix that up while we shuffle this code, since it doesn't have an actual impact at runtime. Otherwise no semantic and behavioural changes intended, just code extraction and adjusting comments and names. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Hildenbrand <david@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-11-daniel.vetter@ffwll.ch
2020-11-27 17:41:24 +01:00
/dev/mem: Revoke mappings when a driver claims the region Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit 90a545e98126 ("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-21 14:06:17 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
drivers/char/mem: implement splice() for /dev/zero, /dev/full This allows splicing zeroed pages into a pipe, and allows discarding pages from a pipe by splicing them to /dev/zero. Writing to /dev/zero should have the same effect as writing to /dev/null, and a "splice_write" implementation exists only for /dev/null. (The /dev/zero splice_read implementation could be optimized by pushing references to the global zero page to the pipe, but that's an optimization for another day.) Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Link: https://lore.kernel.org/r/20230919073743.1066313-1-max.kellermann@ionos.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19 09:37:42 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers: char: mem: Make /dev/mem an optional device Adds Kconfig option CONFIG_DEVMEM that allows the /dev/mem device to be disabled. Option defaults to /dev/mem enabled. Signed-off-by: Rob Ward <robert.ward114@googlemail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-07 15:40:33 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 01:50:16 -07:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
fs: move FMODE_UNSIGNED_OFFSET to fop_flags This is another flag that is statically set and doesn't need to use up an FMODE_* bit. Move it to ->fop_flags and free up another FMODE_* bit. (1) mem_open() used from proc_mem_operations (2) adi_open() used from adi_fops (3) drm_open_helper(): (3.1) accel_open() used from DRM_ACCEL_FOPS (3.2) drm_open() used from (3.2.1) amdgpu_driver_kms_fops (3.2.2) psb_gem_fops (3.2.3) i915_driver_fops (3.2.4) nouveau_driver_fops (3.2.5) panthor_drm_driver_fops (3.2.6) radeon_driver_kms_fops (3.2.7) tegra_drm_fops (3.2.8) vmwgfx_driver_fops (3.2.9) xe_driver_fops (3.2.10) DRM_GEM_FOPS (3.2.11) DEFINE_DRM_GEM_DMA_FOPS (4) struct memdev sets fmode flags based on type of device opened. For devices using struct mem_fops unsigned offset is used. Mark all these file operations as FOP_UNSIGNED_OFFSET and add asserts into the open helper to ensure that the flag is always set. Link: https://lore.kernel.org/r/20240809-work-fop_unsigned-v1-1-658e054d893e@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-09 12:38:56 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] make more file_operation structs static Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 00:24:21 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
[PATCH] splice: add ->splice_write support for /dev/null Useful for testing. Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-26 14:40:08 +02:00
/dev/null: add IORING_OP_URING_CMD support This patch adds support for the io_uring command pass through, aka IORING_OP_URING_CMD, to the /dev/null driver. As with all of the /dev/null functionality, the implementation is just a simple sink where commands go to die, but it should be useful for developers who need a simple IORING_OP_URING_CMD test device that doesn't require any special hardware. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-08-19 16:20:33 -04:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/port: don't compile file operations without CONFIG_DEVPORT In the future inb() and friends will not be available when compiling with CONFIG_HAS_IOPORT=n so we must only try to access them here if CONFIG_DEVPORT is set which depends on HAS_IOPORT. Co-developed-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Link: https://lore.kernel.org/r/20240404114917.3627747-2-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-04 13:49:17 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/port: don't compile file operations without CONFIG_DEVPORT In the future inb() and friends will not be available when compiling with CONFIG_HAS_IOPORT=n so we must only try to access them here if CONFIG_DEVPORT is set which depends on HAS_IOPORT. Co-developed-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Link: https://lore.kernel.org/r/20240404114917.3627747-2-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-04 13:49:17 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] make more file_operation structs static Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 00:24:21 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
/dev/zero: also implement ->read Christophe reported a major speedup due to avoiding the iov_iter overhead, so just add this trivial function. Note that /dev/zero already implements both an iter and non-iter writes so this just makes it more symmetric. Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20200903155922.1111551-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-03 17:59:22 +02:00
switch drivers/char/mem.c to ->read_iter/->write_iter Note that _these_ guys have ->read() and ->write() left in place - they are eqiuvalent to what we'd get if we replaced those with NULL, but we are talking about hot paths here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-03 15:57:04 -04:00
drivers/char/mem: implement splice() for /dev/zero, /dev/full This allows splicing zeroed pages into a pipe, and allows discarding pages from a pipe by splicing them to /dev/zero. Writing to /dev/zero should have the same effect as writing to /dev/null, and a "splice_write" implementation exists only for /dev/null. (The /dev/zero splice_read implementation could be optimized by pushing references to the global zero page to the pipe, but that's an optimization for another day.) Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Link: https://lore.kernel.org/r/20230919073743.1066313-1-max.kellermann@ionos.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19 09:37:42 +02:00
mm: update mem char driver to use mmap_prepare Update the mem char driver (backing /dev/mem and /dev/zero) to use f_op->mmap_prepare hook rather than the deprecated f_op->mmap. The /dev/zero implementation has a very unique and rather concerning characteristic in that it converts MAP_PRIVATE mmap() mappings anonymous when they are, in fact, not. The new f_op->mmap_prepare() can support this, but rather than introducing a helper function to perform this hack (and risk introducing other users), utilise the success hook to do so. We utilise the newly introduced shmem_zero_setup_desc() to allow for the shared mapping case via an f_op->mmap_prepare() hook. We also use the desc->action_error_hook to filter the remap error to -EAGAIN to keep behaviour consistent. Link: https://lkml.kernel.org/r/48f60764d7a6901819d1af778fa33b775d2e8c77.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:31 +01:00
shmem: get_unmapped_area align huge page Provide a shmem_get_unmapped_area method in file_operations, called at mmap time to decide the mapping address. It could be conditional on CONFIG_TRANSPARENT_HUGEPAGE, but save #ifdefs in other places by making it unconditional. shmem_get_unmapped_area() first calls the usual mm->get_unmapped_area (which we treat as a black box, highly dependent on architecture and config and executable layout). Lots of conditions, and in most cases it just goes with the address that chose; but when our huge stars are rightly aligned, yet that did not provide a suitable address, go back to ask for a larger arena, within which to align the mapping suitably. There have to be some direct calls to shmem_get_unmapped_area(), not via the file_operations: because of the way shmem_zero_setup() is called to create a shmem object late in the mmap sequence, when MAP_SHARED is requested with MAP_ANONYMOUS or /dev/zero. Though this only matters when /proc/sys/vm/shmem_huge has been set. Link: http://lkml.kernel.org/r/1466021202-61880-29-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 15:26:15 -07:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] make more file_operation structs static Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 00:24:21 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
switch /dev/zero and /dev/full to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-18 10:04:12 -04:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem: implement splice() for /dev/zero, /dev/full This allows splicing zeroed pages into a pipe, and allows discarding pages from a pipe by splicing them to /dev/zero. Writing to /dev/zero should have the same effect as writing to /dev/null, and a "splice_write" implementation exists only for /dev/null. (The /dev/zero splice_read implementation could be optimized by pushing references to the global zero page to the pipe, but that's an optimization for another day.) Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Link: https://lore.kernel.org/r/20230919073743.1066313-1-max.kellermann@ionos.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-19 09:37:42 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
drivers/char/mem.c: shrink character device's devlist[] array Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 17:54:05 +03:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
drivers: char: mem: Make /dev/mem an optional device Adds Kconfig option CONFIG_DEVMEM that allows the /dev/mem device to be disabled. Option defaults to /dev/mem enabled. Signed-off-by: Rob Ward <robert.ward114@googlemail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-07 15:40:33 +00:00
fs: move FMODE_UNSIGNED_OFFSET to fop_flags This is another flag that is statically set and doesn't need to use up an FMODE_* bit. Move it to ->fop_flags and free up another FMODE_* bit. (1) mem_open() used from proc_mem_operations (2) adi_open() used from adi_fops (3) drm_open_helper(): (3.1) accel_open() used from DRM_ACCEL_FOPS (3.2) drm_open() used from (3.2.1) amdgpu_driver_kms_fops (3.2.2) psb_gem_fops (3.2.3) i915_driver_fops (3.2.4) nouveau_driver_fops (3.2.5) panthor_drm_driver_fops (3.2.6) radeon_driver_kms_fops (3.2.7) tegra_drm_fops (3.2.8) vmwgfx_driver_fops (3.2.9) xe_driver_fops (3.2.10) DRM_GEM_FOPS (3.2.11) DEFINE_DRM_GEM_DMA_FOPS (4) struct memdev sets fmode flags based on type of device opened. For devices using struct mem_fops unsigned offset is used. Mark all these file operations as FOP_UNSIGNED_OFFSET and add asserts into the open helper to ensure that the flag is always set. Link: https://lore.kernel.org/r/20240809-work-fop_unsigned-v1-1-658e054d893e@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-09 12:38:56 +02:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
drivers/char/mem.c: shrink character device's devlist[] array Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 17:54:05 +03:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
drivers/char/mem.c: shrink character device's devlist[] array Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 17:54:05 +03:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
drivers/char/mem.c: shrink character device's devlist[] array Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 17:54:05 +03:00
printk - fix compilation for CONFIG_PRINTK=n Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-09 01:37:51 +02:00
drivers/char/mem.c: shrink character device's devlist[] array Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 17:54:05 +03:00
printk - fix compilation for CONFIG_PRINTK=n Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-09 01:37:51 +02:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
mem_class: Drop the bkl from memory_open() The generic open callback for the mem class devices is "protected" by the bkl. Let's look at the datas manipulated inside memory_open: - inode and file: safe - the devlist: safe because it is constant - the memdev classes inside this array are safe too (constant) After we find out which memdev file operation we need to use, we call its open callback. Depending on the targeted memdev, we call either open_port() that doesn't manipulate any racy data (just a capable() check), or we call nothing. So it's safe to remove the big kernel lock there. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1255113062-5835-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-09 20:31:02 +02:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
mem_class: Drop the bkl from memory_open() The generic open callback for the mem class devices is "protected" by the bkl. Let's look at the datas manipulated inside memory_open: - inode and file: safe - the devlist: safe because it is constant - the memdev classes inside this array are safe too (constant) After we find out which memdev file operation we need to use, we call its open callback. Depending on the targeted memdev, we call either open_port() that doesn't manipulate any racy data (just a capable() check), or we call nothing. So it's safe to remove the big kernel lock there. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1255113062-5835-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-09 20:31:02 +02:00
drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 16:27:48 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:32 +01:00
vfs: introduce FMODE_UNSIGNED_OFFSET for allowing negative f_pos Now, rw_verify_area() checsk f_pos is negative or not. And if negative, returns -EINVAL. But, some special files as /dev/(k)mem and /proc/<pid>/mem etc.. has negative offsets. And we can't do any access via read/write to the file(device). So introduce FMODE_UNSIGNED_OFFSET to allow negative file offsets. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-01 14:20:22 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
mem_class: Drop the bkl from memory_open() The generic open callback for the mem class devices is "protected" by the bkl. Let's look at the datas manipulated inside memory_open: - inode and file: safe - the devlist: safe because it is constant - the memdev classes inside this array are safe too (constant) After we find out which memdev file operation we need to use, we call its open callback. Depending on the targeted memdev, we call either open_port() that doesn't manipulate any racy data (just a capable() check), or we call nothing. So it's safe to remove the big kernel lock there. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1255113062-5835-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-09 20:31:02 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] make more file_operation structs static Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 00:24:21 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-15 18:52:59 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
driver core: make struct class.devnode() take a const * The devnode() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <axboe@kernel.dk> Cc: Justin Sanders <justin@coraid.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com> Cc: Liam Mark <lmark@codeaurora.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Brian Starkey <Brian.Starkey@arm.com> Cc: John Stultz <jstultz@google.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Sean Young <sean@mess.org> Cc: Frank Haverkamp <haver@linux.ibm.com> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Xie Yongji <xieyongji@bytedance.com> Cc: Gautam Dawar <gautam.dawar@xilinx.com> Cc: Dan Carpenter <error27@gmail.com> Cc: Eli Cohen <elic@nvidia.com> Cc: Parav Pandit <parav@nvidia.com> Cc: Maxime Coquelin <maxime.coquelin@redhat.com> Cc: alsa-devel@alsa-project.org Cc: dri-devel@lists.freedesktop.org Cc: kvm@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-block@vger.kernel.org Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23 13:25:20 +01:00
Driver-Core: extend devnode callbacks to provide permissions This allows subsytems to provide devtmpfs with non-default permissions for the device node. Instead of the default mode of 0600, null, zero, random, urandom, full, tty, ptmx now have a mode of 0666, which allows non-privileged processes to access standard device nodes in case no other userspace process applies the expected permissions. This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-18 23:01:12 +02:00
/dev/mem: make mem_class a static const structure Now that the driver core allows for struct class to be in read-only memory, move the mem_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Cc: Arnd Bergmann <arnd@arndb.de> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620143751.578239-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-20 16:37:55 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: make mem_class a static const structure Now that the driver core allows for struct class to be in read-only memory, move the mem_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Cc: Arnd Bergmann <arnd@arndb.de> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620143751.578239-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-20 16:37:55 +02:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
drivers/char/mem.c: cleanups - fix switch statement layout - fix whitespace stuff - fix comment layout - remove unneeded inlining - use __weak - remove trailing whitespace - move uncached_access() inside `#ifndef __HAVE_PHYS_MEM_ACCESS_PROT' - it is otherwise unused. Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-10 15:21:52 -08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/dev/mem: make mem_class a static const structure Now that the driver core allows for struct class to be in read-only memory, move the mem_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Cc: Arnd Bergmann <arnd@arndb.de> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620143751.578239-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-20 16:37:55 +02:00
devmem: handle class_create() failure I hit this when we had a bug in IDR for a few days. Basically sysfs would fail to create new inodes since it uses an IDR and therefore class_create would fail. While we are unlikely to see this fail we may as well handle it instead of oopsing. Signed-off-by: Anton Blanchard <anton@samba.org> Reviewed-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-06 14:34:55 -07:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
powerpc: Disable /dev/port interface on systems without an ISA bridge Some power systems do not have legacy ISA devices. So, /dev/port is not a valid interface on these systems. User level tools such as kbdrate is trying to access the device using this interface which is causing the system crash. This patch will fix this issue by not creating this interface on these powerpc systems. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-11 15:18:44 +10:00
drivers/char/mem.c: fix small coding style issues This patch fixes four foo * bar errors, and one trailing whitespace complaint from checkpatch.pl Signed-off-by: Hans Grob <H.Grob@physik.uni-muenchen.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-06 11:37:20 +01:00
powerpc: Disable /dev/port interface on systems without an ISA bridge Some power systems do not have legacy ISA devices. So, /dev/port is not a valid interface on these systems. User level tools such as kbdrate is trying to access the device using this interface which is causing the system crash. This patch will fix this issue by not creating this interface on these powerpc systems. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-11 15:18:44 +10:00
/dev/mem: make mem_class a static const structure Now that the driver core allows for struct class to be in read-only memory, move the mem_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Cc: Arnd Bergmann <arnd@arndb.de> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620143751.578239-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-20 16:37:55 +02:00
mem_class: use minor as index instead of searching the array Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-04 16:51:29 +02:00
Driver core: change mem class_devices to be real devices Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-25 17:13:31 -07:00
Fix init ordering of /dev/console vs callers of modprobe Make /dev/console get initialised before any initialisation routine that invokes modprobe because if modprobe fails, it's going to want to open /dev/console, presumably to write an error message to. The problem with that is that if the /dev/console driver is not yet initialised, the chardev handler will call request_module() to invoke modprobe, which will fail, because we never compile /dev/console as a module. This will lead to a modprobe loop, showing the following in the kernel log: request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 This can happen, for example, when the built in md5 module can't find the built in cryptomgr module (because the latter fails to initialise). The md5 module comes before the call to tty_init(), presumably because 'crypto' comes before 'drivers' alphabetically. Fix this by calling tty_init() from chrdev_init(). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-06 16:34:43 +01:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00