------------[ cut here ]------------
workqueue: cannot queue hci_cmd_timeout on wq hci2
WARNING: CPU: 2 PID: 46 at kernel/workqueue.c:2255 __queue_work+0xd03/0x1160 kernel/workqueue.c:2254
Modules linked in:
CPU: 2 UID: 0 PID: 46 Comm: kworker/u32:2 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
Workqueue: iou_exit io_ring_exit_work
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 fe ab 8b e8 de 4b f7 ff 90 <0f> 0b 90 90 e9 2f f7 ff ff e8 3f 53 38 00 90 0f 0b 90 e9 b4 f5 ff
RSP: 0018:ffffc90000538be8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817a02c8
RDX: ffff888020774880 RSI: ffffffff817a02d5 RDI: 0000000000000001
RBP: ffff888042378970 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920000a718f
R13: 0000000000000101 R14: ffffffff8182c6b0 R15: ffff88804b0ba978
FS:  0000000000000000(0000) GS:ffff8880976c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f71e3b20 CR3: 000000004bab4000 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+0x219/0x8e0 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:preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7288
Code: df 55 65 48 8b 2d 9c f9 43 08 53 48 89 eb 48 c1 eb 03 48 01 c3 bf 01 00 00 00 e8 ef 4a f6 f5 e8 0a 18 31 f6 fb bf 01 00 00 00 <e8> af 99 ff ff 9c 58 fa f6 c4 02 75 1e bf 01 00 00 00 e8 ed d5 f5
RSP: 0018:ffffc900006df4a8 EFLAGS: 00000206
RAX: 000000000025b3a3 RBX: ffffed10040ee910 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8de4cbd1 RDI: 0000000000000001
RBP: ffff888020774880 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90ab8397 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: 6f 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 d2 22 14 0f 0f 82 74 02 00 00 8b 35 6a 54 14 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 29 6f 3e 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900006df570 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c10a0 RCX: 000000004ec8061d
RDX: 0000000000000000 RSI: ffffffff8de2771d RDI: ffffffff8c162d00
RBP: 0000000000000002 R08: fca52341cb84ddaa R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
 kmalloc_noprof include/linux/slab.h:905 [inline]
 slab_free_hook mm/slub.c:2369 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x142/0x4d0 mm/slub.c:4782
 __io_req_caches_free+0x90/0x3d0 io_uring/io_uring.c:2770
 io_req_caches_free io_uring/io_uring.c:2782 [inline]
 io_ring_exit_work+0x387/0x10a0 io_uring/io_uring.c:2980
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	df 55 65             	fists  0x65(%rbp)
   3:	48 8b 2d 9c f9 43 08 	mov    0x843f99c(%rip),%rbp        # 0x843f9a6
   a:	53                   	push   %rbx
   b:	48 89 eb             	mov    %rbp,%rbx
   e:	48 c1 eb 03          	shr    $0x3,%rbx
  12:	48 01 c3             	add    %rax,%rbx
  15:	bf 01 00 00 00       	mov    $0x1,%edi
  1a:	e8 ef 4a f6 f5       	call   0xf5f64b0e
  1f:	e8 0a 18 31 f6       	call   0xf631182e
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 af 99 ff ff       	call   0xffff99de <-- trapping instruction
  2f:	9c                   	pushf
  30:	58                   	pop    %rax
  31:	fa                   	cli
  32:	f6 c4 02             	test   $0x2,%ah
  35:	75 1e                	jne    0x55
  37:	bf 01 00 00 00       	mov    $0x1,%edi
  3c:	e8                   	.byte 0xe8
  3d:	ed                   	in     (%dx),%eax
  3e:	d5                   	(bad)
  3f:	f5                   	cmc