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1,309,163 commits

Author SHA1 Message Date
Carlos Bilbao
96408beeef docs/sp_SP: Add translation of process/maintainer-kvm-x86.rst
Translate Documentation/process/maintainer-kvm-x86.rst into Spanish.

Co-developed-by: Juan Embid <jembid@ucm.es>
Signed-off-by: Juan Embid <jembid@ucm.es>
Signed-off-by: Carlos Bilbao <carlos.bilbao.osdev@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
[jc: fixed apply- and build-time warnings]
Link: https://lore.kernel.org/r/20240626221942.2780668-1-carlos.bilbao.osdev@gmail.com
2024-07-03 16:34:59 -06:00
Florian Westphal
9f6958ba2e netfilter: nf_tables: unconditionally flush pending work before notifier
syzbot reports:

KASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831
KASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530
KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597
Read of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45
[..]
Workqueue: events nf_tables_trans_destroy_work
Call Trace:
 nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline]
 nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline]
 nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597

Problem is that the notifier does a conditional flush, but its possible
that the table-to-be-removed is still referenced by transactions being
processed by the worker, so we need to flush unconditionally.

We could make the flush_work depend on whether we found a table to delete
in nf-next to avoid the flush for most cases.

AFAICS this problem is only exposed in nf-next, with
commit e169285f8c ("netfilter: nf_tables: do not store nft_ctx in transaction objects"),
with this commit applied there is an unconditional fetch of
table->family which is whats triggering the above splat.

Fixes: 2c9f029328 ("netfilter: nf_tables: flush pending destroy work before netlink notifier")
Reported-and-tested-by: syzbot+4fd66a69358fc15ae2ad@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4fd66a69358fc15ae2ad
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-07-04 00:28:27 +02:00
Matthew Brost
627c961d67 drm/xe: Add timeout to preempt fences
To adhere to dma fencing rules that fences must signal within a
reasonable amount of time, add a 5 second timeout to preempt fences. If
this timeout occurs, kill the associated VM as this fatal to the VM.

v2:
 - Add comment for smp_wmb (Checkpatch)
 - Fix kernel doc typo (Inspection)
 - Add comment for killed check (Niranjana)
v3:
 - Drop smp_wmb (Matthew Auld)
 - Don't take vm->lock in preempt fence worker (Matthew Auld)
 - Drop RB given changes to patch
v4:
 - Add WRITE/READ_ONCE (Niranjana)
 - Don't export xe_vm_kill (Niranjana)

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Tested-by: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240626004137.4060806-1-matthew.brost@intel.com
2024-07-03 15:27:50 -07:00
Daniel Watson
6b2fa426df docs/admin-guide/mm: correct typo 'quired' to 'queried'
Convert the word "quired" to the word "queried" which makes more
sense in this context.

Signed-off-by: Daniel Watson <ozzloy@each.do>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/878qymrjrg.fsf@trent-reznor
2024-07-03 16:22:36 -06:00
Dmitry Torokhov
df472c2b69 Add libps2 to the input section of driver-api
libps2 has been using kerneldoc to document its methods, but was not
actually plugged into driver-api.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/ZoMQhkyUQYi1Bx4t@google.com
2024-07-03 16:20:49 -06:00
SeongJae Park
d436a97181 Docs/mm/index: move allocation profiling document to unsorted documents chapter
The memory allocation profiling document was added to the bottom of the
new outline.  Apparently it was not decided by well-defined guidelines
or a thorough discussions.  Rather than that, it was added there just
because there was no place for such unsorted documents.  Now there is
the chapter.  Move the document to the new place.

Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240701190512.49379-5-sj@kernel.org
2024-07-03 16:19:15 -06:00
SeongJae Park
9472274c92 Docs/mm/index: rename 'Legacy Documentation' to 'Unsorted Documentation'
The intention of 'Legacy Documentation' chapter is to keep the old
documents that not yet sorted into the new outline, and encourage new
documents to be integrated in the new outline from the beginning.

However, the new outline will take some more time to be completed.  It
has started about two years ago, and still many parts are not yet
written.  Also, there is no clear guidline for placing each document for
all cases, for not only the 'legacy' documents, but also for new
documents.  For example, memory allocation profiling document has been
added to the bottom of the new outline.  Apparently it was not following
some well-defined guideliens or a result of a discussion.

Furthermore, the title ("legacy") makes people feel the documents on the
chapter might be outdated or not actively maintained.

Rename 'Legacy Documentation' to 'Unsorted Documentation' and remove the
description saying it is for 'older' documents.  After this change, new
documents that not clear enough where it should be placed on the new
outline can be added on the chapter while well-defined guidelines or
discussion for the new outline is made.

Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240701190512.49379-4-sj@kernel.org
2024-07-03 16:19:15 -06:00
SeongJae Park
8c678c9ca7 Docs/mm/index: Remove 'Memory Management Guide' chapter marker
'Memory Management Guide' chapter aims to be not an additional chapter
of the document, but the ultimate single outline of the document.  In
the sense, marking it as a chapter under the document makes no sense,
and the rendered document looks odd.  Remove the chapter marker.

Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240701190512.49379-3-sj@kernel.org
2024-07-03 16:19:15 -06:00
SeongJae Park
51c702b0ae Docs/mm/allocation-profiling: mark 'Theory of operation' as chapter
'Theory of operation' part of allocation-profiling document is
apparently a chapter.  However, it is mistakenly marked as a document
title.  As a result, rendered mm document index page shows two items for
the document.  Fix it to be marked as a chapter.

Signed-off-by: SeongJae Park <sj@kernel.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240701190512.49379-2-sj@kernel.org
2024-07-03 16:19:15 -06:00
Piotr Wojtaszczyk
f63b94be69 i2c: pnx: Fix potential deadlock warning from del_timer_sync() call in isr
When del_timer_sync() is called in an interrupt context it throws a warning
because of potential deadlock. The timer is used only to exit from
wait_for_completion() after a timeout so replacing the call with
wait_for_completion_timeout() allows to remove the problematic timer and
its related functions altogether.

Fixes: 41561f28e7 ("i2c: New Philips PNX bus driver")
Signed-off-by: Piotr Wojtaszczyk <piotr.wojtaszczyk@timesys.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2024-07-04 00:17:47 +02:00
Ian Rogers
1059fb5291 perf dsos: When adding a dso into sorted dsos maintain the sort order
dsos__add would add at the end of the dso array possibly requiring a
later find to re-sort the array. Patterns of find then add were
becoming O(n*log n) due to the sorts. Change the add routine to be
O(n) rather than O(1) but to maintain the sorted-ness of the dsos
array so that later finds don't need the O(n*log n) sort.

Fixes: 3f4ac23a99 ("perf dsos: Switch backing storage to array from rbtree/list")
Reported-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Steinar Gunderson <sesse@google.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Matt Fleming <matt@readmodwrite.com>
Link: https://lore.kernel.org/r/20240703172117.810918-3-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-07-03 15:02:53 -07:00
Ian Rogers
feaaa8be0b perf comm str: Avoid sort during insert
The array is sorted, so just move the elements and insert in order.

Fixes: 13ca628716 ("perf comm: Add reference count checking to 'struct comm_str'")
Reported-by: Matt Fleming <matt@readmodwrite.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Matt Fleming <matt@readmodwrite.com>
Cc: Steinar Gunderson <sesse@google.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20240703172117.810918-2-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-07-03 14:59:15 -07:00
Linus Torvalds
795c58e4c7 tracing: Fix ioctl conflict with memmapped ring buffer ioctl
It was reported that the ioctl() number used to update the ring buffer
 memory mapping conflicted with the TCGETS ioctl causing strace to report:
 
   $ strace -e ioctl stty
   ioctl(0, TCGETS or TRACE_MMAP_IOCTL_GET_READER, {c_iflag=ICRNL|IXON, c_oflag=NL0|CR0|TAB0|BS0|VT0|FF0|OPOST|ONLCR, c_cflag=B38400|CS8|CREAD, c_lflag=ISIG|ICANON|ECHO|ECHOE|ECHOK|IEXTEN|ECHOCTL|ECHOKE, ...}) = 0
 
 Since this ioctl hasn't been in a full release yet, change it from "T", 0x1
 to "R" 0x20, and also reserve 0x20-0x2F for future ioctl commands, as
 some more are being worked on for the future.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZoW49RQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qhnxAP9gKeqaiBFcPQ9fVJB3pBfP960asb8b
 UfAR0BwxjrLn3AD/Wv7HpzawRmirdeDL2sx7XIKdLCY8hknWWNot/CGibww=
 =BKeF
 -----END PGP SIGNATURE-----

Merge tag 'trace-v6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fix from Steven Rostedt:
 "Fix ioctl conflict with memmapped ring buffer ioctl

  It was reported that the ioctl() number used to update the ring buffer
  memory mapping conflicted with the TCGETS ioctl causing strace to
  report:

    $ strace -e ioctl stty
    ioctl(0, TCGETS or TRACE_MMAP_IOCTL_GET_READER, {c_iflag=ICRNL|IXON, c_oflag=NL0|CR0|TAB0|BS0|VT0|FF0|OPOST|ONLCR, c_cflag=B38400|CS8|CREAD, c_lflag=ISIG|ICANON|ECHO|ECHOE|ECHOK|IEXTEN|ECHOCTL|ECHOKE, ...}) = 0

  Since this ioctl hasn't been in a full release yet, change it from
  "T", 0x1 to "R" 0x20, and also reserve 0x20-0x2F for future ioctl
  commands, as some more are being worked on for the future"

* tag 'trace-v6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Have memmapped ring buffer use ioctl of "R" range 0x20-2F
2024-07-03 14:54:35 -07:00
Wei Liu
fea93a3e5d
PCI: hv: Return zero, not garbage, when reading PCI_INTERRUPT_PIN
The intent of the code snippet is to always return 0 for both
PCI_INTERRUPT_LINE and PCI_INTERRUPT_PIN.

The check misses PCI_INTERRUPT_PIN. This patch fixes that.

This is discovered by this call in VFIO:

    pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);

The old code does not set *val to 0 because it misses the check for
PCI_INTERRUPT_PIN. Garbage is returned in that case.

Fixes: 4daace0d8c ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs")
Link: https://lore.kernel.org/linux-pci/20240701202606.129606-1-wei.liu@kernel.org
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Cc: stable@kernel.org
2024-07-03 21:11:14 +00:00
Andreas Kemnade
80e64b6d34
dt-bindings: mfd: twl: Fix example
Fix example to also conform to rules specified in the separate
not-included gpadc binding.

Fixes: 62e4f33961 ("dt-bindings: regulator: twl-regulator: convert to yaml")
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Reported-by: Rob Herring (Arm) <robh@kernel.org>
Acked-by: Lee Jones <lee@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240612134039.1089839-1-andreas@kemnade.info
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 22:01:26 +01:00
Dmitry Torokhov
5e13bea78d Input: cypress_ps2 - use u8 when dealing with byte data
When dealing with byte data use u8 instead of unsigned char or int.
Stop layering error handling in cypress_ps2_sendbyte() and simply
pass on error code from ps2_sendbyte().

Additionally use u8 instead of unisgned char throughout the code.

Link: https://lore.kernel.org/r/20240628224728.2180126-5-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-07-03 13:48:53 -07:00
Dmitry Torokhov
93f25f92fc Input: cypress_ps2 - propagate errors from lower layers
Do not override errors reported by lower layers with generic "-1",
but propagate them to the callers. Change the checks for errors to be
in the form of "if (error)" to maintain consistency.

Link: https://lore.kernel.org/r/20240628224728.2180126-4-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-07-03 13:48:53 -07:00
Dmitry Torokhov
8bccf667f6 Input: cypress_ps2 - report timeouts when reading command status
Report -ETIMEDOUT error code from cypress_ps2_read_cmd_status() when
device does not send enough data within the allotted time in response
to a command.

Link: https://lore.kernel.org/r/20240628224728.2180126-3-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-07-03 13:48:53 -07:00
Dmitry Torokhov
e8688b93ce Input: cypress_ps2 - fix error handling when sending command fails
Stop layering error handling in cypress_ps2_sendbyte() and simply
pass on error code from ps2_sendbyte() and use it in the callers.

This fixes mishandling of error condition in
cypress_ps2_read_cmd_status() which expects errors to be negative.

Reported-by: Igor Artemiev <Igor.A.Artemiev@mcst.ru>
Link: https://lore.kernel.org/r/20240628224728.2180126-2-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-07-03 13:48:53 -07:00
Dmitry Torokhov
c1a3390011 Input: cypress_ps2 - clean up setting reporting rate
Casting an integer field containing desired rate to a pointer to bytes
works on little endian architectures where the driver is used, but not
a good practice. Use a temporary of proper type instead.

Link: https://lore.kernel.org/r/20240628224728.2180126-1-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-07-03 13:48:53 -07:00
Krzysztof Kozlowski
67820eb9f4
ASoC: codecs: lpass-wsa-macro: Simplify with cleanup.h
Driver's probe() has two allocations which are needed only within the
probe() itself - for devm_regmap_init_mmio().

Usage of devm interface is a bit misleading here, because these can be
freed right after each scope finishes.

This makes the code a bit more obvious and self documenting.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-6-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:42 +01:00
Krzysztof Kozlowski
c72585d792
ASoC: codecs: lpass-rx-macro: Use unsigned for number of widgets
Driver uses ARRAY_SIZE() to get number of widgets later passed to
snd_soc_dapm_new_controls(), which is an 'unsigned int'.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-5-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:41 +01:00
Krzysztof Kozlowski
bf95919fe1
ASoC: dapm: Use unsigned for number of widgets in snd_soc_dapm_new_controls()
Number of widgets in array passed to snd_soc_dapm_new_controls() cannot
be negative, so make it explicit by using 'unsigned int', just like
snd_soc_add_component_controls() is doing.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-4-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:40 +01:00
Krzysztof Kozlowski
0c02cacf62
ASoC: codecs: lpass-rx-macro: Keep static regmap_config as const
The driver has static 'struct regmap_config', which is then customized
depending on device version.  This works fine, because there should not
be two devices in a system simultaneously and even less likely that such
two devices would have different versions, thus different regmap config.
However code is cleaner and more obvious when static data in the driver
is also const - it serves as a template.

Mark the 'struct regmap_config' as const and duplicate it in the probe()
with kmemdup to allow customizing per detected device variant.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-3-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:39 +01:00
Krzysztof Kozlowski
ee5e13b2c9
ASoC: codecs: lpass-rx-macro: Simplify with cleanup.h
Allocate the default register values array with scoped/cleanup.h to
reduce number of error paths and make code a bit simpler.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-2-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:38 +01:00
Krzysztof Kozlowski
891168dc4a
ASoC: codecs: lpass-rx-macro: Simplify PDS cleanup with devm
Eliminate PDS cleanup by using devm_add_action_or_reset() which results
in one less error path and smaller cleanup in remove().

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240701-b4-qcom-audio-lpass-codec-cleanups-v3-1-6d98d4dd1ef5@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:43:37 +01:00
Steven Rostedt (Google)
4ecaf7e98a tracing: Have memmapped ring buffer use ioctl of "R" range 0x20-2F
To prevent conflicts with other ioctl numbers to allow strace to have an
idea of what is happening, add the range of ioctls for the trace buffer
mapping from _IO("T", 0x1) to the range of "R" 0x20 - 0x2F.

Link: https://lore.kernel.org/linux-trace-kernel/20240630105322.GA17573@altlinux.org/
Link: https://lore.kernel.org/linux-trace-kernel/20240630213626.GA23566@altlinux.org/

Cc: Jonathan Corbet <corbet@lwn.net>
Fixes: cf9f0f7c4c ("tracing: Allow user-space mapping of the ring-buffer")
Link: https://lore.kernel.org/20240702153354.367861db@rorschach.local.home
Reported-by: "Dmitry V. Levin" <ldv@strace.io>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-07-03 16:40:45 -04:00
Linus Walleij
3b628e617b
ASoC: tas5086: Convert to GPIO descriptors
Switch the driver to use GPIO descriptors.

Notice that we let the gpiolib handle line inversion for the
active low reset line (nreset !reset).

There are no upstream device trees using the tas5086 compatible
string, if there were, we would need to ascertain that they all
set the GPIO_ACTIVE_LOW flag on their GPIO lines.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patch.msgid.link/20240701-asoc-tas-gpios-v1-1-d69ec5d79939@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-03 21:28:36 +01:00
Song Shuai
c562ba719d
riscv: kexec: Avoid deadlock in kexec crash path
If the kexec crash code is called in the interrupt context, the
machine_kexec_mask_interrupts() function will trigger a deadlock while
trying to acquire the irqdesc spinlock and then deactivate irqchip in
irq_set_irqchip_state() function.

Unlike arm64, riscv only requires irq_eoi handler to complete EOI and
keeping irq_set_irqchip_state() will only leave this possible deadlock
without any use. So we simply remove it.

Link: https://lore.kernel.org/linux-riscv/20231208111015.173237-1-songshuaishuai@tinylab.org/
Fixes: b17d19a531 ("riscv: kexec: Fixup irq controller broken in kexec crash path")
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Reviewed-by: Ryo Takakura <takakura@valinux.co.jp>
Link: https://lore.kernel.org/r/20240626023316.539971-1-songshuaishuai@tinylab.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 13:11:30 -07:00
Puranjay Mohan
393da6cbb2
riscv: stacktrace: fix usage of ftrace_graph_ret_addr()
ftrace_graph_ret_addr() takes an `idx` integer pointer that is used to
optimize the stack unwinding. Pass it a valid pointer to utilize the
optimizations that might be available in the future.

The commit is making riscv's usage of ftrace_graph_ret_addr() match
x86_64.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20240618145820.62112-1-puranjay@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 13:10:03 -07:00
Charlie Jenkins
3582ce0d7c
riscv: selftests: Fix vsetivli args for clang
Clang does not support implicit LMUL in the vset* instruction sequences.
Introduce an explicit LMUL in the vsetivli instruction.

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Fixes: 9d5328eeb1 ("riscv: selftests: Add signal handling vector tests")
Link: https://lore.kernel.org/r/20240702-fix_sigreturn_test-v1-1-485f88a80612@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 13:04:54 -07:00
Palmer Dabbelt
210ac17ded
Merge patch series "Assorted fixes in RISC-V PMU driver"
Atish Patra <atishp@rivosinc.com> says:

This series contains 3 fixes out of which the first one is a new fix
for invalid event data reported in lkml[2]. The last two are v3 of Samuel's
patch[1]. I added the RB/TB/Fixes tag and moved 1 unrelated change
to its own patch. I also changed an error message in kvm vcpu_pmu from
pr_err to pr_debug to avoid redundant failure error messages generated
due to the boot time quering of events implemented in the patch[1]

Here is the original cover letter for the patch[1]

Before this patch:
$ perf list hw

List of pre-defined events (to be used in -e or -M):

  branch-instructions OR branches                    [Hardware event]
  branch-misses                                      [Hardware event]
  bus-cycles                                         [Hardware event]
  cache-misses                                       [Hardware event]
  cache-references                                   [Hardware event]
  cpu-cycles OR cycles                               [Hardware event]
  instructions                                       [Hardware event]
  ref-cycles                                         [Hardware event]
  stalled-cycles-backend OR idle-cycles-backend      [Hardware event]
  stalled-cycles-frontend OR idle-cycles-frontend    [Hardware event]

$ perf stat -ddd true

 Performance counter stats for 'true':

              4.36 msec task-clock                       #    0.744 CPUs utilized
                 1      context-switches                 #  229.325 /sec
                 0      cpu-migrations                   #    0.000 /sec
                38      page-faults                      #    8.714 K/sec
         4,375,694      cycles                           #    1.003 GHz                         (60.64%)
           728,945      instructions                     #    0.17  insn per cycle
            79,199      branches                         #   18.162 M/sec
            17,709      branch-misses                    #   22.36% of all branches
           181,734      L1-dcache-loads                  #   41.676 M/sec
             5,547      L1-dcache-load-misses            #    3.05% of all L1-dcache accesses
     <not counted>      LLC-loads                                                               (0.00%)
     <not counted>      LLC-load-misses                                                         (0.00%)
     <not counted>      L1-icache-loads                                                         (0.00%)
     <not counted>      L1-icache-load-misses                                                   (0.00%)
     <not counted>      dTLB-loads                                                              (0.00%)
     <not counted>      dTLB-load-misses                                                        (0.00%)
     <not counted>      iTLB-loads                                                              (0.00%)
     <not counted>      iTLB-load-misses                                                        (0.00%)
     <not counted>      L1-dcache-prefetches                                                    (0.00%)
     <not counted>      L1-dcache-prefetch-misses                                               (0.00%)

       0.005860375 seconds time elapsed

       0.000000000 seconds user
       0.010383000 seconds sys

After this patch:
$ perf list hw

List of pre-defined events (to be used in -e or -M):

  branch-instructions OR branches                    [Hardware event]
  branch-misses                                      [Hardware event]
  cache-misses                                       [Hardware event]
  cache-references                                   [Hardware event]
  cpu-cycles OR cycles                               [Hardware event]
  instructions                                       [Hardware event]

$ perf stat -ddd true

 Performance counter stats for 'true':

              5.16 msec task-clock                       #    0.848 CPUs utilized
                 1      context-switches                 #  193.817 /sec
                 0      cpu-migrations                   #    0.000 /sec
                37      page-faults                      #    7.171 K/sec
         5,183,625      cycles                           #    1.005 GHz
           961,696      instructions                     #    0.19  insn per cycle
            85,853      branches                         #   16.640 M/sec
            20,462      branch-misses                    #   23.83% of all branches
           243,545      L1-dcache-loads                  #   47.203 M/sec
             5,974      L1-dcache-load-misses            #    2.45% of all L1-dcache accesses
   <not supported>      LLC-loads
   <not supported>      LLC-load-misses
   <not supported>      L1-icache-loads
   <not supported>      L1-icache-load-misses
   <not supported>      dTLB-loads
            19,619      dTLB-load-misses
   <not supported>      iTLB-loads
             6,831      iTLB-load-misses
   <not supported>      L1-dcache-prefetches
   <not supported>      L1-dcache-prefetch-misses

       0.006085625 seconds time elapsed

       0.000000000 seconds user
       0.013022000 seconds sys

[1] https://lore.kernel.org/linux-riscv/20240418014652.1143466-1-samuel.holland@sifive.com/
[2] https://lore.kernel.org/all/CC51D53B-846C-4D81-86FC-FBF969D0A0D6@pku.edu.cn/

* b4-shazam-merge:
  perf: RISC-V: Check standard event availability
  drivers/perf: riscv: Reset the counter to hpmevent mapping while starting cpus
  drivers/perf: riscv: Do not update the event data if uptodate

Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-0-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 12:57:41 -07:00
Samuel Holland
16d3b1af09
perf: RISC-V: Check standard event availability
The RISC-V SBI PMU specification defines several standard hardware and
cache events. Currently, all of these events are exposed to userspace,
even when not actually implemented. They appear in the `perf list`
output, and commands like `perf stat` try to use them.

This is more than just a cosmetic issue, because the PMU driver's .add
function fails for these events, which causes pmu_groups_sched_in() to
prematurely stop scheduling in other (possibly valid) hardware events.

Add logic to check which events are supported by the hardware (i.e. can
be mapped to some counter), so only usable events are reported to
userspace. Since the kernel does not know the mapping between events and
possible counters, this check must happen during boot, when no counters
are in use. Make the check asynchronous to minimize impact on boot time.

Fixes: e999143459 ("RISC-V: Add perf platform driver based on SBI PMU extension")

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-3-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 12:56:22 -07:00
Samuel Holland
7dd646cf74
drivers/perf: riscv: Reset the counter to hpmevent mapping while starting cpus
Currently, we stop all the counters while a new cpu is brought online.
However, the hpmevent to counter mappings are not reset. The firmware may
have some stale encoding in their mapping structure which may lead to
undesirable results. We have not encountered such scenario though.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-2-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 12:56:21 -07:00
Atish Patra
a3f24e83d1
drivers/perf: riscv: Do not update the event data if uptodate
In case of an counter overflow, the event data may get corrupted
if called from an external overflow handler. This happens because
we can't update the counter without starting it when SBI PMU
extension is in use. However, the prev_count has been already
updated at the first pass while the counter value is still the
old one.

The solution is simple where we don't need to update it again
if it is already updated which can be detected using hwc state.
The event state in the overflow handler is updated in the following
patch. Thus, this fix can't be backported to kernel version where
overflow support was added.

Fixes: a8625217a0 ("drivers/perf: riscv: Implement SBI PMU snapshot function")

Closes:https://lore.kernel.org/all/CC51D53B-846C-4D81-86FC-FBF969D0A0D6@pku.edu.cn/

Reported-by: garthlei@pku.edu.cn
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-1-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-03 12:56:15 -07:00
Luca Boccassi
6fce1f40e9 dm verity: add support for signature verification with platform keyring
Add a new configuration CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG_PLATFORM_KEYRING
that enables verifying dm-verity signatures using the platform keyring,
which is populated using the UEFI DB certificates. This is useful for
self-enrolled systems that do not use MOK, as the secondary keyring which
is already used for verification, if the relevant kconfig is enabled, is
linked to the machine keyring, which gets its certificates loaded from MOK.
On datacenter/virtual/cloud deployments it is more common to deploy one's
own certificate chain directly in DB on first boot in unattended mode,
rather than relying on MOK, as the latter typically requires interactive
authentication to enroll, and is more suited for personal machines.

Default to the same value as DM_VERITY_VERIFY_ROOTHASH_SIG_SECONDARY_KEYRING
if not otherwise specified, as it is likely that if one wants to use
MOK certificates to verify dm-verity volumes, DB certificates are
going to be used too. Keys in DB are allowed to load a full kernel
already anyway, so they are already highly privileged.

Signed-off-by: Luca Boccassi <bluca@debian.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:11 +02:00
Benjamin Marzinski
3199a34bfa dm-raid: Fix WARN_ON_ONCE check for sync_thread in raid_resume
rm-raid devices will occasionally trigger the following warning when
being resumed after a table load because DM_RECOVERY_RUNNING is set:

WARNING: CPU: 7 PID: 5660 at drivers/md/dm-raid.c:4105 raid_resume+0xee/0x100 [dm_raid]

The failing check is:
WARN_ON_ONCE(test_bit(MD_RECOVERY_RUNNING, &mddev->recovery));

This check is designed to make sure that the sync thread isn't
registered, but md_check_recovery can set MD_RECOVERY_RUNNING without
the sync_thread ever getting registered. Instead of checking if
MD_RECOVERY_RUNNING is set, check if sync_thread is non-NULL.

Fixes: 16c4770c75 ("dm-raid: really frozen sync_thread during suspend")
Suggested-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:11 +02:00
Eric Biggers
b76ad88442 dm-verity: hash blocks with shash import+finup when possible
Currently dm-verity computes the hash of each block by using multiple
calls to the "ahash" crypto API.  While the exact sequence depends on
the chosen dm-verity settings, in the vast majority of cases it is:

    1. crypto_ahash_init()
    2. crypto_ahash_update() [salt]
    3. crypto_ahash_update() [data]
    4. crypto_ahash_final()

This is inefficient for two main reasons:

- It makes multiple indirect calls, which is expensive on modern CPUs
  especially when mitigations for CPU vulnerabilities are enabled.

  Since the salt is the same across all blocks on a given dm-verity
  device, a much more efficient sequence would be to do an import of the
  pre-salted state, then a finup.

- It uses the ahash (asynchronous hash) API, despite the fact that
  CPU-based hashing is almost always used in practice, and therefore it
  experiences the overhead of the ahash-based wrapper for shash.

  Because dm-verity was intentionally converted to ahash to support
  off-CPU crypto accelerators, a full reversion to shash might not be
  acceptable.  Yet, we should still provide a fast path for shash with
  the most common dm-verity settings.

  Another reason for shash over ahash is that the upcoming multibuffer
  hashing support, which is specific to CPU-based hashing, is much
  better suited for shash than for ahash.  Supporting it via ahash would
  add significant complexity and overhead.  And it's not possible for
  the "same" code to properly support both multibuffer hashing and HW
  accelerators at the same time anyway, given the different computation
  models.  Unfortunately there will always be code specific to each
  model needed (for users who want to support both).

Therefore, this patch adds a new shash import+finup based fast path to
dm-verity.  It is used automatically when appropriate.  This makes
dm-verity optimized for what the vast majority of users want: CPU-based
hashing with the most common settings, while still retaining support for
rarer settings and off-CPU crypto accelerators.

In benchmarks with veritysetup's default parameters (SHA-256, 4K data
and hash block sizes, 32-byte salt), which also match the parameters
that Android currently uses, this patch improves block hashing
performance by about 15% on x86_64 using the SHA-NI instructions, or by
about 5% on arm64 using the ARMv8 SHA2 instructions.  On x86_64 roughly
two-thirds of the improvement comes from the use of import and finup,
while the remaining third comes from the switch from ahash to shash.

Note that another benefit of using "import" to handle the salt is that
if the salt size is equal to the input size of the hash algorithm's
compression function, e.g. 64 bytes for SHA-256, then the performance is
exactly the same as no salt.  This doesn't seem to be much better than
veritysetup's current default of 32-byte salts, due to the way SHA-256's
finalization padding works, but it should be marginally better.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:11 +02:00
Eric Biggers
e8f5e93301 dm-verity: make verity_hash() take dm_verity_io instead of ahash_request
In preparation for adding shash support to dm-verity, change
verity_hash() to take a pointer to a struct dm_verity_io instead of a
pointer to the ahash_request embedded inside it.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:11 +02:00
Eric Biggers
cf715f4b7e dm-verity: always "map" the data blocks
dm-verity needs to access data blocks by virtual address in three
different cases (zeroization, recheck, and forward error correction),
and one more case (shash support) is coming.  Since it's guaranteed that
dm-verity data blocks never cross pages, and kmap_local_page and
kunmap_local are no-ops on modern platforms anyway, just unconditionally
"map" every data block's page and work with the virtual buffer directly.
This simplifies the code and eliminates unnecessary overhead.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:11 +02:00
Eric Biggers
09d1430896 dm-verity: provide dma_alignment limit in io_hints
Since Linux v6.1, some filesystems support submitting direct I/O that is
aligned to only dma_alignment instead of the logical_block_size
alignment that was required before.  I/O that is not aligned to the
logical_block_size is difficult to handle in device-mapper targets that
do cryptographic processing of data, as it makes the units of data that
are hashed or encrypted possibly be split across pages, creating rarely
used and rarely tested edge cases.

As such, dm-crypt and dm-integrity have already opted out of this by
setting dma_alignment to 'logical_block_size - 1'.

Although dm-verity does have code that handles these cases (or at least
is intended to do so), supporting direct I/O with such a low amount of
alignment is not really useful on dm-verity devices.  So, opt dm-verity
out of it too so that it's not necessary to handle these edge cases.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:41:08 +02:00
Eric Biggers
a7ddb3d49d dm-verity: make real_digest and want_digest fixed-length
Change the digest fields in struct dm_verity_io from variable-length to
fixed-length, since their maximum length is fixed at
HASH_MAX_DIGESTSIZE, i.e. 64 bytes, which is not too big.  This is
simpler and makes the fields a bit faster to access.

(HASH_MAX_DIGESTSIZE did not exist when this code was written, which may
explain why it wasn't used.)

This makes the verity_io_real_digest() and verity_io_want_digest()
functions trivial, but this patch leaves them in place temporarily since
most of their callers will go away in a later patch anyway.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:33:17 +02:00
Anna-Maria Behnsen
59dbee7d4d tick/sched: Combine WARN_ON_ONCE and print_once
When the WARN_ON_ONCE() triggers, the printk() of the additional
information related to the warning will not happen in print level
"warn". When reading dmesg with a restriction to level "warn", the
information published by the printk_once() will not show up there.

Transform WARN_ON_ONCE() and printk_once() into a WARN_ONCE().

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240610103552.25252-1-anna-maria@linutronix.de
2024-07-03 21:32:55 +02:00
Eric Biggers
e41e52e59e dm-verity: move data hash mismatch handling into its own function
Move the code that handles mismatches of data block hashes into its own
function so that it doesn't clutter up verity_verify_io().

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-03 21:32:15 +02:00
Ryusuke Konishi
93aef9eda1 nilfs2: fix incorrect inode allocation from reserved inodes
If the bitmap block that manages the inode allocation status is corrupted,
nilfs_ifile_create_inode() may allocate a new inode from the reserved
inode area where it should not be allocated.

Previous fix commit d325dc6eb7 ("nilfs2: fix use-after-free bug of
struct nilfs_root"), fixed the problem that reserved inodes with inode
numbers less than NILFS_USER_INO (=11) were incorrectly reallocated due to
bitmap corruption, but since the start number of non-reserved inodes is
read from the super block and may change, in which case inode allocation
may occur from the extended reserved inode area.

If that happens, access to that inode will cause an IO error, causing the
file system to degrade to an error state.

Fix this potential issue by adding a wraparound option to the common
metadata object allocation routine and by modifying
nilfs_ifile_create_inode() to disable the option so that it only allocates
inodes with inode numbers greater than or equal to the inode number read
in "nilfs->ns_first_ino", regardless of the bitmap status of reserved
inodes.

Link: https://lkml.kernel.org/r/20240623051135.4180-4-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:25 -07:00
Ryusuke Konishi
bb76c6c274 nilfs2: add missing check for inode numbers on directory entries
Syzbot reported that mounting and unmounting a specific pattern of
corrupted nilfs2 filesystem images causes a use-after-free of metadata
file inodes, which triggers a kernel bug in lru_add_fn().

As Jan Kara pointed out, this is because the link count of a metadata file
gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(),
tries to delete that inode (ifile inode in this case).

The inconsistency occurs because directories containing the inode numbers
of these metadata files that should not be visible in the namespace are
read without checking.

Fix this issue by treating the inode numbers of these internal files as
errors in the sanity check helper when reading directory folios/pages.

Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer
analysis.

Link: https://lkml.kernel.org/r/20240623051135.4180-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+d79afb004be235636ee8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d79afb004be235636ee8
Reported-by: Jan Kara <jack@suse.cz>
Closes: https://lkml.kernel.org/r/20240617075758.wewhukbrjod5fp5o@quack3
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:24 -07:00
Ryusuke Konishi
e2fec219a3 nilfs2: fix inode number range checks
Patch series "nilfs2: fix potential issues related to reserved inodes".

This series fixes one use-after-free issue reported by syzbot, caused by
nilfs2's internal inode being exposed in the namespace on a corrupted
filesystem, and a couple of flaws that cause problems if the starting
number of non-reserved inodes written in the on-disk super block is
intentionally (or corruptly) changed from its default value.  


This patch (of 3):

In the current implementation of nilfs2, "nilfs->ns_first_ino", which
gives the first non-reserved inode number, is read from the superblock,
but its lower limit is not checked.

As a result, if a number that overlaps with the inode number range of
reserved inodes such as the root directory or metadata files is set in the
super block parameter, the inode number test macros (NILFS_MDT_INODE and
NILFS_VALID_INODE) will not function properly.

In addition, these test macros use left bit-shift calculations using with
the inode number as the shift count via the BIT macro, but the result of a
shift calculation that exceeds the bit width of an integer is undefined in
the C specification, so if "ns_first_ino" is set to a large value other
than the default value NILFS_USER_INO (=11), the macros may potentially
malfunction depending on the environment.

Fix these issues by checking the lower bound of "nilfs->ns_first_ino" and
by preventing bit shifts equal to or greater than the NILFS_USER_INO
constant in the inode number test macros.

Also, change the type of "ns_first_ino" from signed integer to unsigned
integer to avoid the need for type casting in comparisons such as the
lower bound check introduced this time.

Link: https://lkml.kernel.org/r/20240623051135.4180-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20240623051135.4180-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:24 -07:00
Jan Kara
385d838df2 mm: avoid overflows in dirty throttling logic
The dirty throttling logic is interspersed with assumptions that dirty
limits in PAGE_SIZE units fit into 32-bit (so that various multiplications
fit into 64-bits).  If limits end up being larger, we will hit overflows,
possible divisions by 0 etc.  Fix these problems by never allowing so
large dirty limits as they have dubious practical value anyway.  For
dirty_bytes / dirty_background_bytes interfaces we can just refuse to set
so large limits.  For dirty_ratio / dirty_background_ratio it isn't so
simple as the dirty limit is computed from the amount of available memory
which can change due to memory hotplug etc.  So when converting dirty
limits from ratios to numbers of pages, we just don't allow the result to
exceed UINT_MAX.

This is root-only triggerable problem which occurs when the operator
sets dirty limits to >16 TB.

Link: https://lkml.kernel.org/r/20240621144246.11148-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-By: Zach O'Keefe <zokeefe@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:24 -07:00
Jan Kara
30139c7020 Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again"
Patch series "mm: Avoid possible overflows in dirty throttling".

Dirty throttling logic assumes dirty limits in page units fit into
32-bits.  This patch series makes sure this is true (see patch 2/2 for
more details).


This patch (of 2):

This reverts commit 9319b64790.

The commit is broken in several ways.  Firstly, the removed (u64) cast
from the multiplication will introduce a multiplication overflow on 32-bit
archs if wb_thresh * bg_thresh >= 1<<32 (which is actually common - the
default settings with 4GB of RAM will trigger this).  Secondly, the
div64_u64() is unnecessarily expensive on 32-bit archs.  We have
div64_ul() in case we want to be safe & cheap.  Thirdly, if dirty
thresholds are larger than 1<<32 pages, then dirty balancing is going to
blow up in many other spectacular ways anyway so trying to fix one
possible overflow is just moot.

Link: https://lkml.kernel.org/r/20240621144017.30993-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240621144246.11148-1-jack@suse.cz
Fixes: 9319b64790 ("mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-By: Zach O'Keefe <zokeefe@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:24 -07:00
Jinliang Zheng
cf3f9a593d mm: optimize the redundant loop of mm_update_owner_next()
When mm_update_owner_next() is racing with swapoff (try_to_unuse()) or
/proc or ptrace or page migration (get_task_mm()), it is impossible to
find an appropriate task_struct in the loop whose mm_struct is the same as
the target mm_struct.

If the above race condition is combined with the stress-ng-zombie and
stress-ng-dup tests, such a long loop can easily cause a Hard Lockup in
write_lock_irq() for tasklist_lock.

Recognize this situation in advance and exit early.

Link: https://lkml.kernel.org/r/20240620122123.3877432-1-alexjlzheng@tencent.com
Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tycho Andersen <tandersen@netflix.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 12:29:24 -07:00