Bluetooth: hci6: hardware error 0x00
============================================
WARNING: possible recursive locking detected
6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Not tainted
--------------------------------------------
kworker/u9:0/12412 is trying to acquire lock:
ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: touch_wq_lockdep_map kernel/workqueue.c:3875 [inline]
ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: __flush_workqueue+0x1b0/0x1710 kernel/workqueue.c:3917

but task is already holding lock:
ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock((wq_completion)hci6);
  lock((wq_completion)hci6);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by kworker/u9:0/12412:
 #0: ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88802ac9f148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc9000415fd00 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc9000415fd00 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312

stack backtrace:
CPU: 1 UID: 0 PID: 12412 Comm: kworker/u9:0 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: hci6 hci_error_reset
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_deadlock kernel/locking/lockdep.c:3061 [inline]
 validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3855
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 touch_wq_lockdep_map kernel/workqueue.c:3875 [inline]
 __flush_workqueue+0x1c9/0x1710 kernel/workqueue.c:3917
 drain_workqueue+0xc9/0x3a0 kernel/workqueue.c:4081
 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5785
 hci_release_dev+0x169/0x16b0 net/bluetooth/hci_core.c:2733
 bt_host_release+0x83/0x90 net/bluetooth/hci_sysfs.c:94
 device_release+0x9b/0x1c0
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x231/0x480 lib/kobject.c:737
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>