KCSAN: data-race in __lru_add_drain_all / __pagevec_lru_add

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 90d9fbc16b69 Merge tag 'usb-5.16-rc5' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=146e0cf5b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9a2598dd2cfceb9b
dashboard link: https://syzkaller.appspot.com/bug?extid=a5ff8b97fcf389a296c4
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a5ff8b...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / __pagevec_lru_add

write to 0xffff888237d277c8 of 1 bytes by task 14525 on cpu 1:
pagevec_reinit include/linux/pagevec.h:56 [inline]
__pagevec_lru_add+0x243/0x270 mm/swap.c:1076
lru_add_drain_cpu+0x6a/0x260 mm/swap.c:613
lru_add_drain+0x21/0x60 mm/swap.c:717
exit_mmap+0x218/0x470 mm/mmap.c:3165
__mmput+0x27/0x1b0 kernel/fork.c:1113
mmput+0x3d/0x50 kernel/fork.c:1134
exit_mm+0xdb/0x170 kernel/exit.c:507
do_exit+0x608/0x17a0 kernel/exit.c:819
do_group_exit+0xce/0x180 kernel/exit.c:929
get_signal+0xfc3/0x1550 kernel/signal.c:2852
arch_do_signal_or_restart+0x8c/0x2e0 arch/x86/kernel/signal.c:868
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
exit_to_user_mode_prepare+0x113/0x190 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237d277c8 of 1 bytes by task 14507 on cpu 0:
pagevec_count include/linux/pagevec.h:61 [inline]
__lru_add_drain_all+0x12c/0x3e0 mm/swap.c:835
lru_add_drain_all+0xc/0x10 mm/swap.c:857
invalidate_bdev+0x56/0x80 block/bdev.c:88
invalidate_disk+0x25/0xb0 block/genhd.c:651
__loop_clr_fd+0x41f/0x6c0 drivers/block/loop.c:1147
loop_clr_fd drivers/block/loop.c:1237 [inline]
lo_ioctl+0x985/0x1270 drivers/block/loop.c:1562
blkdev_ioctl+0x20e/0x440 block/ioctl.c:609
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
__x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x09 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14507 Comm: syz-executor.2 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.