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workqueue: cannot queue hci_cmd_timeout on wq hci3
WARNING: CPU: 0 PID: 3 at kernel/workqueue.c:2255 __queue_work+0xd03/0x1160 kernel/workqueue.c:2254
Modules linked in:
CPU: 0 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__queue_work+0xd03/0x1160 kernel/workqueue.c:2254
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 4b 04 00 00 48 8b 75 18 4c 89 fa 48 c7 c7 20 01 ac 8b e8 be 1e f7 ff 90 <0f> 0b 90 90 e9 2f f7 ff ff e8 8f 7b 38 00 90 0f 0b 90 e9 b4 f5 ff
RSP: 0018:ffffc90000007be8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817a3388
RDX: ffff888100684880 RSI: ffffffff817a3395 RDI: 0000000000000001
RBP: ffff888055bf4970 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000000f8f
R13: 0000000000000100 R14: ffffffff81832490 R15: ffff888046265978
FS:  0000000000000000(0000) GS:ffff8880d66b5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f44d5f9ed58 CR3: 000000000e380000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 call_timer_fn+0x197/0x620 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1793 [inline]
 __run_timers+0x569/0x960 kernel/time/timer.c:2372
 __run_timer_base kernel/time/timer.c:2384 [inline]
 __run_timer_base kernel/time/timer.c:2376 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2393
 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2403
 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lockdep_unregister_key+0xe9/0x140 kernel/locking/lockdep.c:6616
Code: 48 89 ef e8 b9 e5 ff ff 48 83 2d 89 11 5f 14 01 89 c3 e8 da ee ff ff 9c 58 f6 c4 02 75 52 41 f7 c4 00 02 00 00 74 01 fb 84 db <75> 1b 5b 5d 41 5c e9 4c 76 0a 00 8b 05 4a 35 14 0f 31 db 85 c0 74
RSP: 0018:ffffc90000067d98 EFLAGS: 00000246
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8df45976 RDI: ffffffff8c162d00
RBP: ffffffff975b7a38 R08: 000000000001197f R09: ffffffff95f8acde
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000246
R13: ffff888106b36c00 R14: ffff888106b36c08 R15: ffff888029cf2001
 wq_unregister_lockdep kernel/workqueue.c:4816 [inline]
 pwq_release_workfn+0x5e6/0xa70 kernel/workqueue.c:5112
 kthread_worker_fn+0x30d/0xc50 kernel/kthread.c:1010
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	e8 b9 e5 ff ff       	call   0xffffe5c1
   8:	48 83 2d 89 11 5f 14 	subq   $0x1,0x145f1189(%rip)        # 0x145f1199
   f:	01
  10:	89 c3                	mov    %eax,%ebx
  12:	e8 da ee ff ff       	call   0xffffeef1
  17:	9c                   	pushf
  18:	58                   	pop    %rax
  19:	f6 c4 02             	test   $0x2,%ah
  1c:	75 52                	jne    0x70
  1e:	41 f7 c4 00 02 00 00 	test   $0x200,%r12d
  25:	74 01                	je     0x28
  27:	fb                   	sti
  28:	84 db                	test   %bl,%bl
* 2a:	75 1b                	jne    0x47 <-- trapping instruction
  2c:	5b                   	pop    %rbx
  2d:	5d                   	pop    %rbp
  2e:	41 5c                	pop    %r12
  30:	e9 4c 76 0a 00       	jmp    0xa7681
  35:	8b 05 4a 35 14 0f    	mov    0xf14354a(%rip),%eax        # 0xf143585
  3b:	31 db                	xor    %ebx,%ebx
  3d:	85 c0                	test   %eax,%eax
  3f:	74                   	.byte 0x74