[moderation] [block?] KCSAN: data-race in delete_from_page_cache_batch / nr_blockdev_pages (11)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 02c438bbfffe Merge tag 'for-6.10-tag' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16bbb6dc980000
kernel config: https://syzkaller.appspot.com/x/.config?x=1147418d170c6139
dashboard link: https://syzkaller.appspot.com/bug?extid=a342be28c76a8c322aa6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ax...@kernel.dk linux...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e9239cdefd0b/disk-02c438bb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/21294656ce11/vmlinux-02c438bb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f829e43e9cde/bzImage-02c438bb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a342be...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in delete_from_page_cache_batch / nr_blockdev_pages

read-write to 0xffff8881004c0bb8 of 8 bytes by task 22451 on cpu 0:
page_cache_delete_batch mm/filemap.c:324 [inline]
delete_from_page_cache_batch+0x4f4/0x710 mm/filemap.c:343
truncate_inode_pages_range+0x1c5/0x6b0 mm/truncate.c:359
truncate_inode_pages+0x24/0x30 mm/truncate.c:439
kill_bdev block/bdev.c:90 [inline]
blkdev_flush_mapping+0xa5/0x1a0 block/bdev.c:664
blkdev_put_whole block/bdev.c:671 [inline]
bdev_release+0x305/0x430 block/bdev.c:1096
blkdev_release+0x15/0x20 block/fops.c:623
__fput+0x2c2/0x660 fs/file_table.c:422
____fput+0x15/0x20 fs/file_table.c:450
task_work_run+0x13a/0x1a0 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0x5d5/0x1710 kernel/exit.c:874
do_group_exit+0x142/0x150 kernel/exit.c:1023
__do_sys_exit_group kernel/exit.c:1034 [inline]
__se_sys_exit_group kernel/exit.c:1032 [inline]
__x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1032
x64_sys_call+0x27c1/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:232
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

read to 0xffff8881004c0bb8 of 8 bytes by task 4694 on cpu 1:
nr_blockdev_pages+0x7c/0xd0 block/bdev.c:475
si_meminfo+0x87/0xd0 mm/show_mem.c:80
update_defense_level+0x49/0x5b0 net/netfilter/ipvs/ip_vs_ctl.c:102
defense_work_handler+0x1f/0x80 net/netfilter/ipvs/ip_vs_ctl.c:235
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
worker_thread+0x526/0x730 kernel/workqueue.c:3393
kthread+0x1d1/0x210 kernel/kthread.c:389
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4694 Comm: kworker/1:11 Not tainted 6.9.0-syzkaller-12220-g02c438bbfffe #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: events_long defense_work_handler
==================================================================


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