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workqueue: cannot queue hci_cmd_timeout on wq hci0
WARNING: CPU: 1 PID: 6114 at kernel/workqueue.c:2258 __queue_work+0xd38/0xfb0
Modules linked in:
CPU: 1 UID: 0 PID: 6114 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:__queue_work+0xd38/0xfb0
Code: 42 80 3c 20 00 74 08 4c 89 ef e8 03 cd 9b 00 49 8b 75 00 49 81 c7 78 01 00 00 48 c7 c7 20 eb 69 8b 4c 89 fa e8 b9 31 f9 ff 90 <0f> 0b 90 90 e9 1a f5 ff ff e8 aa 17 36 00 90 0f 0b 90 e9 dd fc ff
RSP: 0018:ffffc90000a08b10 EFLAGS: 00010046
RAX: 04aa35516d135c00 RBX: 0000000000000100 RCX: ffff88817216c900
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: 1ffff110229af738 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bba680 R12: dffffc0000000000
R13: ffff888116b70990 R14: 0000000000000008 R15: ffff888114d7b978
FS:  0000000000000000(0000) GS:ffff8882a9f3b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009b40 CR3: 000000016d0ab000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x646/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lockdep_unregister_key+0x2c5/0x310
Code: 65 48 8b 05 7d d8 d0 10 48 3b 44 24 10 0f 84 26 fe ff ff e8 2d e9 a8 09 e8 58 ea a8 09 41 f7 c7 00 02 00 00 74 bd fb 40 84 ed <75> bc eb cd 90 0f 0b 90 e9 19 ff ff ff 90 0f 0b 90 e9 2a ff ff ff
RSP: 0018:ffffc900041a7558 EFLAGS: 00000246
RAX: 04aa35516d135c00 RBX: ffff8881bb44c298 RCX: 04aa35516d135c00
RDX: ffffffff93320358 RSI: ffffffff8d721f55 RDI: ffffffff8bbf0760
RBP: ffff8881bb44c200 R08: 0000000000000000 R09: ffffffff81aa7618
R10: dffffc0000000000 R11: fffffbfff1ef9c4f R12: 0000000000000000
R13: 0000000000001000 R14: 0000000000000001 R15: 0000000000000a06
 __qdisc_destroy+0x166/0x420
 dev_shutdown+0x34c/0x440
 unregister_netdevice_many_notify+0x118c/0x2390
 default_device_exit_batch+0x819/0x890
 ops_undo_list+0x525/0x990
 cleanup_net+0x4d8/0x820
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
