[syzbot] WARNING in pwq_unbound_release_workfn (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2734d6c1b1a0 Linux 5.14-rc2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1518d3bc300000
kernel config: https://syzkaller.appspot.com/x/.config?x=f7dfeb6dfc05ea19
dashboard link: https://syzkaller.appspot.com/bug?extid=d04950c1e97f51d0068a

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+d04950...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 3 PID: 32 at kernel/locking/lockdep.c:6305 lockdep_unregister_key+0x19a/0x250 kernel/locking/lockdep.c:6305
Modules linked in:
CPU: 3 PID: 32 Comm: kworker/3:0 Not tainted 5.14.0-rc2-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: events pwq_unbound_release_workfn
RIP: 0010:lockdep_unregister_key+0x19a/0x250 kernel/locking/lockdep.c:6305
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 8f 00 00 00 4d 89 7d 08 48 b8 22 01 00 00 00 00 ad de 48 89 43 08 eb 02 <0f> 0b 4c 89 f7 ba 01 00 00 00 48 89 ee e8 44 fd ff ff 4c 89 f7 e8
RSP: 0018:ffffc900007bfcb0 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffffffff1ad87cd
RDX: 1ffffffff1fcad55 RSI: 0000000000000004 RDI: ffffffff8fe56aa8
RBP: ffff88801416e928 R08: 0000000000000001 R09: 0000000000000003
R10: fffff520000f7f8c R11: 0000000000086088 R12: 0000000000000246
R13: dffffc0000000000 R14: ffffffff8fcd1868 R15: ffff888047033870
FS: 0000000000000000(0000) GS:ffff88802cd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000014a53ad CR3: 00000000479f1000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
wq_unregister_lockdep kernel/workqueue.c:3468 [inline]
pwq_unbound_release_workfn+0x223/0x2d0 kernel/workqueue.c:3700
process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295


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[Pavel Skripkin]

I think, this should be fixed by:

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a9a2e0482d647b07b4d45033f4be0854d3ea201e

Unfortunately, syzbot didn't provide any reproducer, so no chance to
test it :(



With regards,
Pavel Skripkin

[syzbot]

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