syzbot

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workqueue: cannot queue hci_tx_work on wq hci0
WARNING: kernel/workqueue.c:2298 at __queue_work+0xd3f/0x1040 kernel/workqueue.c:2296, CPU#0: kworker/0:5/5332
Modules linked in:
CPU: 0 UID: 0 PID: 5332 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+0xd67/0x1040 kernel/workqueue.c:2296
Code: a6 0e 49 8d 7d 18 48 89 f8 48 c1 e8 03 42 80 3c 20 00 74 05 e8 0a 5e a5 00 49 8b 75 18 49 81 c7 70 01 00 00 4c 89 f7 4c 89 fa <67> 48 0f b9 3a 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef
RSP: 0018:ffffc9000ccbf760 EFLAGS: 00010082
RAX: 1ffff1100251e18a RBX: 0000000000000008 RCX: ffff88801fa9a500
RDX: ffff8880371dc970 RSI: ffffffff8a9e4cf0 RDI: ffffffff9033ef50
RBP: 0000000000000020 R08: ffff8880128f0c3f R09: 1ffff1100251e187
R10: dffffc0000000000 R11: ffffed100251e188 R12: dffffc0000000000
R13: ffff8880128f0c38 R14: ffffffff9033ef50 R15: ffff8880371dc970
FS:  0000000000000000(0000) GS:ffff88808c87e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000008c00 CR3: 000000000e74a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x106/0x1d0 kernel/workqueue.c:2444
 l2cap_send_conn_req+0x243/0x370 net/bluetooth/l2cap_core.c:1253
 l2cap_start_connection net/bluetooth/l2cap_core.c:1408 [inline]
 l2cap_conn_start+0xb2b/0xf20 net/bluetooth/l2cap_core.c:1549
 l2cap_info_timeout+0x68/0xa0 net/bluetooth/l2cap_core.c:1685
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x389/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	49 8d 7d 18          	lea    0x18(%r13),%rdi
   4:	48 89 f8             	mov    %rdi,%rax
   7:	48 c1 e8 03          	shr    $0x3,%rax
   b:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  10:	74 05                	je     0x17
  12:	e8 0a 5e a5 00       	call   0xa55e21
  17:	49 8b 75 18          	mov    0x18(%r13),%rsi
  1b:	49 81 c7 70 01 00 00 	add    $0x170,%r15
  22:	4c 89 f7             	mov    %r14,%rdi
  25:	4c 89 fa             	mov    %r15,%rdx
* 28:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2d:	4c 89 e8             	mov    %r13,%rax
  30:	48 c1 e8 03          	shr    $0x3,%rax
  34:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  39:	74 08                	je     0x43
  3b:	4c 89 ef             	mov    %r13,%rdi