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Wei Yang ad3c79df5e mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM
commit 18e19f195c upstream.

When we use SPARSEMEM instead of SPARSEMEM_VMEMMAP, pfn_to_page()
doesn't work before sparse_init_one_section() is called.

This leads to a crash when hotplug memory:

    BUG: unable to handle page fault for address: 0000000006400000
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 3 PID: 221 Comm: kworker/u16:1 Tainted: G        W         5.5.0-next-20200205+ #343
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
    Workqueue: kacpi_hotplug acpi_hotplug_work_fn
    RIP: 0010:__memset+0x24/0x30
    Code: cc cc cc cc cc cc 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3
    RSP: 0018:ffffb43ac0373c80 EFLAGS: 00010a87
    RAX: ffffffffffffffff RBX: ffff8a1518800000 RCX: 0000000000050000
    RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000006400000
    RBP: 0000000000140000 R08: 0000000000100000 R09: 0000000006400000
    R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000
    R13: 0000000000000028 R14: 0000000000000000 R15: ffff8a153ffd9280
    FS:  0000000000000000(0000) GS:ffff8a153ab00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000006400000 CR3: 0000000136fca000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     sparse_add_section+0x1c9/0x26a
     __add_pages+0xbf/0x150
     add_pages+0x12/0x60
     add_memory_resource+0xc8/0x210
     __add_memory+0x62/0xb0
     acpi_memory_device_add+0x13f/0x300
     acpi_bus_attach+0xf6/0x200
     acpi_bus_scan+0x43/0x90
     acpi_device_hotplug+0x275/0x3d0
     acpi_hotplug_work_fn+0x1a/0x30
     process_one_work+0x1a7/0x370
     worker_thread+0x30/0x380
     kthread+0x112/0x130
     ret_from_fork+0x35/0x40

We should use memmap as it did.

On x86 the impact is limited to x86_32 builds, or x86_64 configurations
that override the default setting for SPARSEMEM_VMEMMAP.

Other memory hotplug archs (arm64, ia64, and ppc) also default to
SPARSEMEM_VMEMMAP=y.

[dan.j.williams@intel.com: changelog update]
{rppt@linux.ibm.com: changelog update]
Link: http://lkml.kernel.org/r/20200219030454.4844-1-bhe@redhat.com
Fixes: ba72b4c8cf ("mm/sparsemem: support sub-section hotplug")
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2020-02-28 17:23:36 +01:00
arch MIPS: ingenic: DTS: Fix watchdog nodes 2020-02-28 17:23:35 +01:00
block block, bfq: do not plug I/O for bfq_queues with no proc refs 2020-02-24 08:38:09 +01:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto crypto: essiv - fix AEAD capitalization and preposition use in help text 2020-02-24 08:38:32 +01:00
Documentation fbdev: fix numbering of fbcon options 2020-02-24 08:38:21 +01:00
drivers nvme-multipath: Fix memory leak with ana_log_buf 2020-02-28 17:23:36 +01:00
fs jbd2: fix ocfs2 corrupt when clearing block group bits 2020-02-28 17:23:34 +01:00
include genirq/irqdomain: Make sure all irq domain flags are distinct 2020-02-28 17:23:36 +01:00
init Revert "um: Enable CONFIG_CONSTRUCTORS" 2020-02-01 09:33:00 +00:00
ipc Revert "ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()" 2020-02-28 17:23:36 +01:00
kernel tracing: Fix now invalid var_ref_vals assumption in trace action 2020-02-24 08:38:47 +01:00
lib lib/scatterlist.c: adjust indentation in __sg_alloc_table 2020-02-24 08:38:47 +01:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM 2020-02-28 17:23:36 +01:00
net sunrpc: Fix potential leaks in sunrpc_cache_unhash() 2020-02-24 08:38:40 +01:00
samples samples/bpf: Set -fno-stack-protector when building BPF programs 2020-02-24 08:38:15 +01:00
scripts bpf, btf: Always output invariant hit in pahole DWARF to BTF transform 2020-02-24 08:38:40 +01:00
security selinux: ensure we cleanup the internal AVC counters on error in avc_update() 2020-02-24 08:38:19 +01:00
sound ASoC: sun8i-codec: Fix setting DAI data format 2020-02-28 17:23:27 +01:00
tools tc-testing: add missing 'nsPlugin' to basic.json 2020-02-24 08:38:49 +01:00
usr gen_initramfs_list.sh: fix 'bad variable name' error 2020-01-04 00:00:48 +09:00
virt KVM: arm64: Treat emulated TVAL TimerValue as a signed 32-bit integer 2020-02-14 16:53:04 -05:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap MAINTAINERS: update my email address 2020-01-11 14:33:39 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS MAINTAINERS: Update drm/i915 bug filing URL 2020-02-28 17:23:36 +01:00
Makefile Linux 5.5.6 2020-02-24 08:38:51 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.