Bluetooth: hci0: command 0x2016 tx timeout
------------[ cut here ]------------
refcnt < 0
WARNING: net/bluetooth/hci_conn.c:631 at hci_conn_timeout+0x16a/0x230 net/bluetooth/hci_conn.c:631, CPU#3: kworker/u34:3/5746
Modules linked in:
CPU: 3 UID: 0 PID: 5746 Comm: kworker/u34:3 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: hci0 hci_conn_timeout
RIP: 0010:hci_conn_timeout+0x16a/0x230 net/bluetooth/hci_conn.c:631
Code: 44 0f b6 2d 93 9c 4a 06 31 ff 41 83 e5 40 44 89 ee e8 0a 59 7d f7 45 84 ed 0f 84 02 ff ff ff e9 30 8c e5 f6 e8 e7 5e 7d f7 90 <0f> 0b 90 e8 de 5e 7d f7 48 8d bb fd f5 ff ff 48 b8 00 00 00 00 00
RSP: 0000:ffffc90004fcfc18 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888013bdca40 RCX: ffffffff8a8b5b9f
RDX: ffff888024aaca80 RSI: ffffffff8a8b5c99 RDI: ffff888024aaca80
RBP: 00000000ffffffff R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffffff R11: 746f6f7465756c42 R12: ffff888013bdc000
R13: ffff888024aacf44 R14: ffffffff90da8a44 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88809741f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7248850 CR3: 0000000068d38000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>