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Jeongjun Park 8001070cfb mm: migrate: annotate data-race in migrate_folio_unmap()
I found a report from syzbot [1]

This report shows that the value can be changed, but in reality, the
value of __folio_set_movable() cannot be changed because it holds the
folio refcount.

Therefore, it is appropriate to add an annotate to make KCSAN
ignore that data-race.

[1]

==================================================================
BUG: KCSAN: data-race in __filemap_remove_folio / migrate_pages_batch

write to 0xffffea0004b81dd8 of 8 bytes by task 6348 on cpu 0:
 page_cache_delete mm/filemap.c:153 [inline]
 __filemap_remove_folio+0x1ac/0x2c0 mm/filemap.c:233
 filemap_remove_folio+0x6b/0x1f0 mm/filemap.c:265
 truncate_inode_folio+0x42/0x50 mm/truncate.c:178
 shmem_undo_range+0x25b/0xa70 mm/shmem.c:1028
 shmem_truncate_range mm/shmem.c:1144 [inline]
 shmem_evict_inode+0x14d/0x530 mm/shmem.c:1272
 evict+0x2f0/0x580 fs/inode.c:731
 iput_final fs/inode.c:1883 [inline]
 iput+0x42a/0x5b0 fs/inode.c:1909
 dentry_unlink_inode+0x24f/0x260 fs/dcache.c:412
 __dentry_kill+0x18b/0x4c0 fs/dcache.c:615
 dput+0x5c/0xd0 fs/dcache.c:857
 __fput+0x3fb/0x6d0 fs/file_table.c:439
 ____fput+0x1c/0x30 fs/file_table.c:459
 task_work_run+0x13a/0x1a0 kernel/task_work.c:228
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004b81dd8 of 8 bytes by task 6342 on cpu 1:
 __folio_test_movable include/linux/page-flags.h:699 [inline]
 migrate_folio_unmap mm/migrate.c:1199 [inline]
 migrate_pages_batch+0x24c/0x1940 mm/migrate.c:1797
 migrate_pages_sync mm/migrate.c:1963 [inline]
 migrate_pages+0xff1/0x1820 mm/migrate.c:2072
 do_mbind mm/mempolicy.c:1390 [inline]
 kernel_mbind mm/mempolicy.c:1533 [inline]
 __do_sys_mbind mm/mempolicy.c:1607 [inline]
 __se_sys_mbind+0xf76/0x1160 mm/mempolicy.c:1603
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1603
 x64_sys_call+0x2b4d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:238
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888127601078 -> 0x0000000000000000

Link: https://lkml.kernel.org/r/20240924130053.107490-1-aha310510@gmail.com
Fixes: 7e2a5e5ab2 ("mm: migrate: use __folio_test_movable()")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-26 14:01:44 -07:00
arch i2c-for-6.12-rc1 2024-09-23 14:34:19 -07:00
block vfs-6.12.blocksize 2024-09-20 17:53:17 -07:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto crypto: aegis128 - Fix indentation issue in crypto_aegis128_process_crypt() 2024-09-13 18:26:52 +08:00
Documentation media updates for v6.12-rc1 2024-09-23 15:27:58 -07:00
drivers media updates for v6.12-rc1 2024-09-23 15:27:58 -07:00
fs NFSD 6.12 Release Notes 2024-09-23 12:01:45 -07:00
include mm/hugetlb: fix memfd_pin_folios resv_huge_pages leak 2024-09-26 14:01:43 -07:00
init sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
io_uring struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
ipc struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
kernel pci-v6.12-changes 2024-09-23 12:47:06 -07:00
lib The core clk framework is left largely untouched this time around except for 2024-09-23 15:01:48 -07:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm mm: migrate: annotate data-race in migrate_folio_unmap() 2024-09-26 14:01:44 -07:00
net NFSD 6.12 Release Notes 2024-09-23 12:01:45 -07:00
rust Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-09-05 20:37:20 -07:00
samples bpf-next-6.12 2024-09-21 09:27:50 -07:00
scripts bpf-next-6.12 2024-09-21 09:27:50 -07:00
security struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
sound firewire updates for v6.12 2024-09-23 12:55:27 -07:00
tools tools: fix shared radix-tree build 2024-09-26 14:01:43 -07:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
.clang-format Docs: Move clang-format from process/ to dev-tools/ 2024-06-26 16:36:00 -06:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: add .gcda files 2024-08-09 13:18:46 +01:00
.mailmap NFSD 6.12 Release Notes 2024-09-23 12:01:45 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Mark powerpc spufs as orphaned 2024-08-19 21:27:56 +10:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS media updates for v6.12-rc1 2024-09-23 15:27:58 -07:00
Makefile Linux 6.11 2024-09-15 16:57:56 +02:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.