[moderation] [io-uring?] KCSAN: data-race in io_sq_thread / io_uring_try_cancel_requests (8)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c2d5304e6c64 Merge tag 'platform-drivers-x86-v6.7-2' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10bab900e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c1151391aefc0c3
dashboard link: https://syzkaller.appspot.com/bug?extid=b4ed079d9cc43ee311ca
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [asml.s...@gmail.com ax...@kernel.dk io-u...@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/40c3b752a9c1/disk-c2d5304e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6ab3363b9f46/vmlinux-c2d5304e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e1685e2593f6/bzImage-c2d5304e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b4ed07...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in io_sq_thread / io_uring_try_cancel_requests

write to 0xffff888158025c38 of 8 bytes by task 21281 on cpu 0:
io_sq_thread+0xbd5/0xc50 io_uring/sqpoll.c:316
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff888158025c38 of 8 bytes by task 20990 on cpu 1:
io_uring_try_cancel_requests+0x1e4/0x680 io_uring/io_uring.c:3351
io_ring_exit_work+0x126/0x4f0 io_uring/io_uring.c:3107
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0xffff8881478a8000 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20990 Comm: kworker/u4:3 Not tainted 6.7.0-rc2-syzkaller-00014-gc2d5304e6c64 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_unbound io_ring_exit_work
==================================================================


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[syzbot]

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