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workqueue: cannot queue hci_cmd_timeout on wq hci0
WARNING: CPU: 2 PID: 18295 at kernel/workqueue.c:2255 __queue_work+0xd03/0x1160 kernel/workqueue.c:2254
Modules linked in:
CPU: 2 UID: 0 PID: 18295 Comm: syz.9.3057 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__queue_work+0xd03/0x1160 kernel/workqueue.c:2254
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 4b 04 00 00 48 8b 75 18 4c 89 fa 48 c7 c7 e0 01 ac 8b e8 de 4b f7 ff 90 <0f> 0b 90 90 e9 2f f7 ff ff e8 8f 54 38 00 90 0f 0b 90 e9 b4 f5 ff
RSP: 0018:ffffc90000538be8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817a02f8
RDX: ffff888012dfa440 RSI: ffffffff817a0305 RDI: 0000000000000001
RBP: ffff888023f50970 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920000a718f
R13: 0000000080000101 R14: ffffffff8182c6e0 R15: ffff888051059978
FS:  0000000000000000(0000) GS:ffff8880976ba000(0063) knlGS:00000000f543eb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000080001000 CR3: 000000006eef8000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 call_timer_fn+0x197/0x620 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1793 [inline]
 __run_timers+0x569/0x960 kernel/time/timer.c:2372
 __run_timer_base kernel/time/timer.c:2384 [inline]
 __run_timer_base kernel/time/timer.c:2376 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2393
 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2403
 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_single+0x1f4/0x6b0 kernel/smp.c:687
Code: 00 00 00 66 44 89 ac 24 ce 00 00 00 48 89 de e8 82 fa ff ff 41 89 c5 0f 1f 44 00 00 e8 35 e2 0b 00 eb 07 e8 2e e2 0b 00 f3 90 <8b> 9c 24 c8 00 00 00 31 ff 83 e3 01 89 de e8 59 dd 0b 00 85 db 75
RSP: 0018:ffffc90002b6f8a0 EFLAGS: 00000287
RAX: 000000000001f363 RBX: 0000000000000001 RCX: ffffc9002d2be000
RDX: 0000000000080000 RSI: ffffffff81af27f2 RDI: 0000000000000005
RBP: ffffc90002b6fa00 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 1ffff9200056df1c
R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000
 rcu_barrier kernel/rcu/tree.c:3867 [inline]
 rcu_barrier+0x28d/0x6e0 kernel/rcu/tree.c:3804
 flush_rcu_work+0x54/0xd0 kernel/workqueue.c:4302
 kvfree_rcu_barrier+0x102/0x1d0 mm/slab_common.c:2083
 kmem_cache_destroy+0x2c/0x170 mm/slab_common.c:492
 p9_client_destroy+0x2dd/0x480 net/9p/client.c:1088
 v9fs_session_close+0x49/0x2d0 fs/9p/v9fs.c:506
 v9fs_kill_super+0x4d/0xa0 fs/9p/vfs_super.c:198
 deactivate_locked_super+0xc1/0x1a0 fs/super.c:474
 v9fs_mount+0x62b/0xa90 fs/9p/vfs_super.c:179
 legacy_get_tree+0x10c/0x220 fs/fs_context.c:666
 vfs_get_tree+0x8e/0x340 fs/super.c:1815
 do_new_mount fs/namespace.c:3808 [inline]
 path_mount+0x1513/0x2000 fs/namespace.c:4123
 do_mount fs/namespace.c:4136 [inline]
 __do_sys_mount fs/namespace.c:4347 [inline]
 __se_sys_mount fs/namespace.c:4324 [inline]
 __ia32_sys_mount+0x28b/0x310 fs/namespace.c:4324
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf704e579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f543e55c EFLAGS: 00000296 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000800002c0
RDX: 0000000080000080 RSI: 0000000000004000 RDI: 0000000080000400
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 66 44             	add    %ah,0x44(%rsi)
   5:	89 ac 24 ce 00 00 00 	mov    %ebp,0xce(%rsp)
   c:	48 89 de             	mov    %rbx,%rsi
   f:	e8 82 fa ff ff       	call   0xfffffa96
  14:	41 89 c5             	mov    %eax,%r13d
  17:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  1c:	e8 35 e2 0b 00       	call   0xbe256
  21:	eb 07                	jmp    0x2a
  23:	e8 2e e2 0b 00       	call   0xbe256
  28:	f3 90                	pause
* 2a:	8b 9c 24 c8 00 00 00 	mov    0xc8(%rsp),%ebx <-- trapping instruction
  31:	31 ff                	xor    %edi,%edi
  33:	83 e3 01             	and    $0x1,%ebx
  36:	89 de                	mov    %ebx,%esi
  38:	e8 59 dd 0b 00       	call   0xbdd96
  3d:	85 db                	test   %ebx,%ebx
  3f:	75                   	.byte 0x75