------------[ cut here ]------------
workqueue: cannot queue hci_conn_timeout on wq hci6
WARNING: kernel/workqueue.c:2251 at __queue_work+0xc9d/0x10e0 kernel/workqueue.c:2250, CPU#0: kworker/0:3/5991
Modules linked in:
CPU: 0 UID: 0 PID: 5991 Comm: kworker/0:3 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events l2cap_chan_timeout
RIP: 0010:__queue_work+0xca1/0x10e0 kernel/workqueue.c:2250
Code: 78 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 0c 04 00 00 48 8d 3d 53 f1 06 0f 48 8b 75 18 <67> 48 0f b9 3a e9 90 f7 ff ff e8 d0 31 3a 00 90 0f 0b 90 e9 15 f6
RSP: 0018:ffffc9000346f9c8 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff88801b49d800 RCX: 1ffff1100c36414b
RDX: ffff88802aac9178 RSI: ffffffff8a6f27d0 RDI: ffffffff908ba5e0
RBP: ffff888061b20a40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000200000 R11: ffff8880229cd4b0 R12: 0000000000000000
R13: ffff88802aac9000 R14: ffff888061b20a88 R15: ffff88802aac9000
FS:  0000000000000000(0000) GS:ffff8880d68f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe7ade8058 CR3: 000000000e184000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __queue_delayed_work+0x35b/0x460 kernel/workqueue.c:2503
 queue_delayed_work_on+0x1b5/0x200 kernel/workqueue.c:2555
 queue_delayed_work include/linux/workqueue.h:684 [inline]
 hci_conn_drop include/net/bluetooth/hci_core.h:1710 [inline]
 hci_conn_drop include/net/bluetooth/hci_core.h:1684 [inline]
 l2cap_chan_del+0x5a0/0x940 net/bluetooth/l2cap_core.c:672
 l2cap_chan_close+0xfe/0xa80 net/bluetooth/l2cap_core.c:845
 l2cap_chan_timeout+0x196/0x340 net/bluetooth/l2cap_core.c:431
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
----------------
Code disassembly (best guess):
   0:	78 01                	js     0x3
   2:	00 00                	add    %al,(%rax)
   4:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   b:	fc ff df
   e:	48 89 f9             	mov    %rdi,%rcx
  11:	48 c1 e9 03          	shr    $0x3,%rcx
  15:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  19:	0f 85 0c 04 00 00    	jne    0x42b
  1f:	48 8d 3d 53 f1 06 0f 	lea    0xf06f153(%rip),%rdi        # 0xf06f179
  26:	48 8b 75 18          	mov    0x18(%rbp),%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 90 f7 ff ff       	jmp    0xfffff7c4
  34:	e8 d0 31 3a 00       	call   0x3a3209
  39:	90                   	nop
  3a:	0f 0b                	ud2
  3c:	90                   	nop
  3d:	e9                   	.byte 0xe9
  3e:	15                   	.byte 0x15
  3f:	f6                   	.byte 0xf6