Bluetooth: hci0: Opcode 0x0c03 failed: -110 ============================================ WARNING: possible recursive locking detected 6.8.0-syzkaller-05243-g14bb1e8c8d4a #0 Not tainted -------------------------------------------- kworker/u9:1/4465 is trying to acquire lock: ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: touch_wq_lockdep_map kernel/workqueue.c:3901 [inline] ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: __flush_workqueue+0x1b0/0x1710 kernel/workqueue.c:3943 but task is already holding lock: ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock((wq_completion)hci0); lock((wq_completion)hci0); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by kworker/u9:1/4465: #0: ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff8880226b2148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335 #1: ffffc9000ecd7d00 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc9000ecd7d00 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x1770 kernel/workqueue.c:3335 stack backtrace: CPU: 1 PID: 4465 Comm: kworker/u9:1 Not tainted 6.8.0-syzkaller-05243-g14bb1e8c8d4a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: hci0 hci_error_reset Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 touch_wq_lockdep_map kernel/workqueue.c:3901 [inline] __flush_workqueue+0x1c9/0x1710 kernel/workqueue.c:3943 drain_workqueue+0xc9/0x3a0 kernel/workqueue.c:4107 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5673 hci_release_dev+0x169/0x16a0 net/bluetooth/hci_core.c:2808 bt_host_release+0x83/0x90 net/bluetooth/hci_sysfs.c:94 device_release+0x99/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22f/0x480 lib/kobject.c:737 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243