WARNING: locking bug in process_one_work

WARNING: locking bug in process_one_work

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    63623fd4 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=155d3529e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5d2e033af114153f
dashboard link: https://syzkaller.appspot.com/bug?extid=5396b943a2f03ed3d510
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+5396b943a2f03ed3d510@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 2895 at kernel/locking/lockdep.c:840 look_up_lock_class+0x1ac/0x2a0 kernel/locking/lockdep.c:839
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 2895 Comm: kworker/0:41 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: rcu_gp srcu_invoke_callbacks
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 panic+0x264/0x7a9 kernel/panic.c:221
 __warn+0x209/0x210 kernel/panic.c:582
 report_bug+0x1b6/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0xcf/0x1c0 arch/x86/kernel/traps.c:267
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:look_up_lock_class+0x1ac/0x2a0 kernel/locking/lockdep.c:839
Code: 57 00 4c 3b 33 74 7d 48 8b 45 c8 42 80 3c 28 00 48 8b 5d d0 74 08 48 89 df e8 00 9c 57 00 48 c7 c0 30 08 a0 89 48 39 03 74 5a <0f> 0b eb 56 e8 8b 0e 41 02 45 31 e4 48 c7 c7 4f 3f e5 88 44 89 fe
RSP: 0018:ffffc90008f3fa10 EFLAGS: 00010002
RAX: ffffffff89a00830 RBX: ffffc90008f3fd78 RCX: ffffc90008f3fd78
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90008f3fd78
RBP: ffffc90008f3fa48 R08: 0000000000000001 R09: 0000000000000000
R10: fffffbfff12d372d R11: 0000000000000000 R12: ffffffff89c2f670
R13: dffffc0000000000 R14: ffffffff88e58667 R15: 0000000000000000
 register_lock_class+0x99/0xeb0 kernel/locking/lockdep.c:1184
 __lock_acquire+0x116/0x1bc0 kernel/locking/lockdep.c:3836
 lock_acquire+0x154/0x250 kernel/locking/lockdep.c:4484
 process_one_work+0x7c8/0x10f0 kernel/workqueue.c:2240
 worker_thread+0xbbc/0x1630 kernel/workqueue.c:2410
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


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