------------[ cut here ]------------
workqueue: cannot queue hci_tx_work on wq hci0
WARNING: kernel/workqueue.c:2271 at __queue_work+0xd53/0x1020 kernel/workqueue.c:2269, CPU#0: kworker/0:5/5328
Modules linked in:
CPU: 0 UID: 0 PID: 5328 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: events l2cap_info_timeout
RIP: 0010:__queue_work+0xd7e/0x1020 kernel/workqueue.c:2269
Code: 83 c5 18 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 23 25 a4 00 49 8b 75 00 49 81 c7 78 01 00 00 4c 89 f7 4c 89 fa <67> 48 0f b9 3a 48 83 c4 58 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc
RSP: 0018:ffffc9000f4f7818 EFLAGS: 00010086
RAX: 1ffff110039b298d RBX: 0000000000000008 RCX: ffff888012198000
RDX: ffff888012818978 RSI: ffffffff8aa1a650 RDI: ffffffff9014cf00
RBP: 0000000000000020 R08: ffff88801cd94c57 R09: 1ffff110039b298a
R10: dffffc0000000000 R11: ffffed10039b298b R12: dffffc0000000000
R13: ffff88801cd94c68 R14: ffffffff9014cf00 R15: ffff888012818978
FS:  0000000000000000(0000) GS:ffff88808ca51000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f10c45b63a0 CR3: 000000000e54c000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x106/0x1d0 kernel/workqueue.c:2405
 l2cap_conn_start+0x5b1/0xff0 net/bluetooth/l2cap_core.c:1552
 l2cap_info_timeout+0x68/0xa0 net/bluetooth/l2cap_core.c:1662
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	83 c5 18             	add    $0x18,%ebp
   3:	4c 89 e8             	mov    %r13,%rax
   6:	48 c1 e8 03          	shr    $0x3,%rax
   a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
   f:	74 08                	je     0x19
  11:	4c 89 ef             	mov    %r13,%rdi
  14:	e8 23 25 a4 00       	call   0xa4253c
  19:	49 8b 75 00          	mov    0x0(%r13),%rsi
  1d:	49 81 c7 78 01 00 00 	add    $0x178,%r15
  24:	4c 89 f7             	mov    %r14,%rdi
  27:	4c 89 fa             	mov    %r15,%rdx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	48 83 c4 58          	add    $0x58,%rsp
  33:	5b                   	pop    %rbx
  34:	41 5c                	pop    %r12
  36:	41 5d                	pop    %r13
  38:	41 5e                	pop    %r14
  3a:	41 5f                	pop    %r15
  3c:	5d                   	pop    %rbp
  3d:	c3                   	ret
  3e:	cc                   	int3
  3f:	cc                   	int3