[syzbot] WARNING in io_try_cancel_userdata (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 40c93d7fff6f Merge tag 'x86-urgent-2021-11-21' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13cac4deb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=152798d01fe6adcd
dashboard link: https://syzkaller.appspot.com/bug?extid=ab0cfe96c2b3cd1c1153
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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+ab0cfe...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 20 at fs/io_uring.c:6269 io_try_cancel_userdata+0x3c5/0x640 fs/io_uring.c:6269
Modules linked in:
CPU: 1 PID: 20 Comm: kworker/1:0 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events io_fallback_req_func
RIP: 0010:io_try_cancel_userdata+0x3c5/0x640 fs/io_uring.c:6269
Code: 44 89 f0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 92 db 95 ff 65 48 8b 04 25 40 70 02 00 49 39 c6 0f 84 a0 fd ff ff e8 7b db 95 ff <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02
RSP: 0018:ffffc90000da7bc8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88803a80d3c0 RCX: 0000000000000000
RDX: ffff888011a38000 RSI: ffffffff81e1bde5 RDI: 0000000000000003
RBP: 1ffff920001b4f7a R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81e1bb37 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88807eaf7000 R14: ffff88803b203a00 R15: ffff88803a80d420
FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2d3db37718 CR3: 000000001c339000 CR4: 0000000000350ee0
Call Trace:
<TASK>
io_req_task_link_timeout+0x6b/0x1e0 fs/io_uring.c:6886
io_fallback_req_func+0xf9/0x1ae fs/io_uring.c:1334
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>


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