KCSAN: data-race in futex_wait_queue_me / io_fail_links

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 68d3fa23 Merge tag 'efi-urgent-for-v5.10-rc3' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=158387f5500000
kernel config: https://syzkaller.appspot.com/x/.config?x=89a86a84f1254241
dashboard link: https://syzkaller.appspot.com/bug?extid=86eb5e48369b89ab0252
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+86eb5e...@syzkaller.appspotmail.com

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

read-write to 0xffff888139729064 of 4 bytes by task 15713 on cpu 1:
freezer_count include/linux/freezer.h:121 [inline]
freezable_schedule include/linux/freezer.h:173 [inline]
futex_wait_queue_me+0x198/0x240 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 0xffff888139729064 of 4 bytes by task 15718 on cpu 0:
io_req_task_work_add fs/io_uring.c:2007 [inline]
io_free_req_deferred fs/io_uring.c:2201 [inline]
io_put_req_deferred fs/io_uring.c:2214 [inline]
io_fail_links+0x1b4/0x650 fs/io_uring.c:1964
__io_req_find_next fs/io_uring.c:1989 [inline]
io_req_find_next fs/io_uring.c:1997 [inline]
io_steal_work fs/io_uring.c:2229 [inline]
io_wq_submit_work+0x716/0x760 fs/io_uring.c:6081
io_worker_handle_work+0xd2a/0x1000 fs/io-wq.c:572
io_wqe_worker+0x202/0x810 fs/io-wq.c:614
kthread+0x1fa/0x220 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15718 Comm: io_wqe_worker-0 Not tainted 5.10.0-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.