KCSAN: data-race in __io_async_wake / futex_wait_queue_me

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4df91062 mm: memcg: relayout structure mem_cgroup to avoid..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=164921ae500000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9b19d1bde60f8d
dashboard link: https://syzkaller.appspot.com/bug?extid=c9d7b6deabea55a1ec7a
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [dvh...@infradead.org linux-...@vger.kernel.org mi...@redhat.com pet...@infradead.org tg...@linutronix.de]

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+c9d7b6...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __io_async_wake / futex_wait_queue_me

read-write to 0xffff888041450024 of 4 bytes by task 9131 on cpu 1:
freezer_do_not_count include/linux/freezer.h:109 [inline]
freezable_schedule include/linux/freezer.h:171 [inline]
futex_wait_queue_me+0x17e/0x240 kernel/futex.c:2604
futex_wait+0x145/0x390 kernel/futex.c:2706
do_futex+0x10ff/0x2140 kernel/futex.c:3765
__do_sys_futex kernel/futex.c:3828 [inline]
__se_sys_futex+0x2a8/0x390 kernel/futex.c:3794
__x64_sys_futex+0x74/0x80 kernel/futex.c:3794
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888041450024 of 4 bytes by task 9127 on cpu 0:
io_req_task_work_add fs/io_uring.c:2007 [inline]
__io_async_wake+0x188/0x370 fs/io_uring.c:4891
io_poll_wake+0x2d/0x40 fs/io_uring.c:5363
__wake_up_common+0xbc/0x130 kernel/sched/wait.c:93
__wake_up_common_lock kernel/sched/wait.c:123 [inline]
__wake_up+0x80/0xc0 kernel/sched/wait.c:142
pipe_release+0x102/0x1c0 fs/pipe.c:711
__fput+0x243/0x4d0 fs/file_table.c:281
____fput+0x11/0x20 fs/file_table.c:314
task_work_run+0x8e/0x110 kernel/task_work.c:151
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191
syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9127 Comm: syz-executor.3 Not tainted 5.10.0-rc5-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.