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workqueue: cannot queue hci_rx_work on wq hci0
WARNING: kernel/workqueue.c:2270 at __queue_work+0xd08/0x1150 kernel/workqueue.c:2269, CPU#1: syz.0.63/6219
Modules linked in:
CPU: 1 UID: 0 PID: 6219 Comm: syz.0.63 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
RIP: 0010:__queue_work+0xd0c/0x1150 kernel/workqueue.c:2269
Code: 00 00 00 fc ff df 49 8d 94 24 78 01 00 00 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 04 04 00 00 48 8d 3d 88 a8 0c 0f 48 8b 75 18 <67> 48 0f b9 3a e9 2a f7 ff ff e8 55 cc 38 00 90 0f 0b 90 e9 b2 f5
RSP: 0018:ffffc900056a7be0 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff110026d417b
RDX: ffff888022f5b978 RSI: ffffffff8a836730 RDI: ffffffff90dc7ae0
RBP: ffff8880136a0bc0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888022f5b800
R13: ffff88802d6ec900 R14: ffff88803f5b9ed8 R15: ffff88802fbc4000
FS:  00007f4eaa1906c0(0000) GS:ffff8880d6447000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000288d7000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x180/0x1e0 kernel/workqueue.c:2405
 queue_work include/linux/workqueue.h:669 [inline]
 hci_recv_frame+0x503/0x880 net/bluetooth/hci_core.c:2969
 vhci_get_user drivers/bluetooth/hci_vhci.c:520 [inline]
 vhci_write+0x384/0x490 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1070 fs/read_write.c:688
 ksys_write+0x12a/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ea935cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f4eaa18ffb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f4eaa1906c0 RCX: 00007f4ea935cfce
RDX: 0000000000000007 RSI: 0000200000000040 RDI: 00000000000000ca
RBP: 00007f4ea9432bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4ea9616128 R14: 00007f4ea9616090 R15: 00007ffc8afe52a8
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 fc                	add    %bh,%ah
   4:	ff                   	lcall  (bad)
   5:	df 49 8d             	fisttps -0x73(%rcx)
   8:	94                   	xchg   %eax,%esp
   9:	24 78                	and    $0x78,%al
   b:	01 00                	add    %eax,(%rax)
   d:	00 48 89             	add    %cl,-0x77(%rax)
  10:	f9                   	stc
  11:	48 c1 e9 03          	shr    $0x3,%rcx
  15:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
  19:	0f 85 04 04 00 00    	jne    0x423
  1f:	48 8d 3d 88 a8 0c 0f 	lea    0xf0ca888(%rip),%rdi        # 0xf0ca8ae
  26:	48 8b 75 18          	mov    0x18(%rbp),%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 2a f7 ff ff       	jmp    0xfffff75e
  34:	e8 55 cc 38 00       	call   0x38cc8e
  39:	90                   	nop
  3a:	0f 0b                	ud2
  3c:	90                   	nop
  3d:	e9                   	.byte 0xe9
  3e:	b2 f5                	mov    $0xf5,%dl