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workqueue: cannot queue hci_rx_work on wq hci0
WARNING: kernel/workqueue.c:2252 at __queue_work+0xd1f/0xf90 kernel/workqueue.c:2250, CPU#0: syz.0.0/5327
Modules linked in:
CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 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+0xd4a/0xf90 kernel/workqueue.c:2250
Code: 83 c5 18 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 57 de 9f 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:ffffc9000c3bfb20 EFLAGS: 00010086
RAX: 1ffff1100229c17b RBX: 0000000000000008 RCX: 0000000000100000
RDX: ffff888037a4a978 RSI: ffffffff8a70c8f0 RDI: ffffffff8fd1fa80
RBP: 0000000000000000 R08: ffff8880114e0bc7 R09: 1ffff1100229c178
R10: dffffc0000000000 R11: ffffed100229c179 R12: dffffc0000000000
R13: ffff8880114e0bd8 R14: ffffffff8fd1fa80 R15: ffff888037a4a978
FS:  00007fea2b1d36c0(0000) GS:ffff88808cf1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b3b0f7910 CR3: 00000000435a2000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x106/0x1c0 kernel/workqueue.c:2386
 queue_work include/linux/workqueue.h:669 [inline]
 hci_recv_frame+0x625/0x7c0 net/bluetooth/hci_core.c:2968
 vhci_get_user drivers/bluetooth/hci_vhci.c:520 [inline]
 vhci_write+0x358/0x4a0 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x61d/0xb90 fs/read_write.c:686
 ksys_write+0x150/0x270 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fea2a35b58e
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:00007fea2b1d2fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fea2b1d36c0 RCX: 00007fea2a35b58e
RDX: 0000000000000007 RSI: 00002000000000c0 RDI: 00000000000000ca
RBP: 00007fea2a408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fea2a616128 R14: 00007fea2a616090 R15: 00007ffe8fa49538
 </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 57 de 9f 00       	call   0x9fde70
  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