BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! turning off the locking correctness validator. CPU: 0 PID: 1621 Comm: kworker/u5:0 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci0 hci_power_on Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 add_chain_cache kernel/locking/lockdep.c:2840 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:2914 [inline] validate_chain kernel/locking/lockdep.c:2935 [inline] __lock_acquire.cold+0x263/0x288 kernel/locking/lockdep.c:3954 lock_acquire+0x197/0x420 kernel/locking/lockdep.c:4484 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xbf kernel/locking/spinlock.c:159 complete+0x13/0x70 kernel/sched/completion.c:32 flush_workqueue_prep_pwqs+0x42c/0x4e0 kernel/workqueue.c:2751 flush_workqueue+0x546/0x14c0 kernel/workqueue.c:2801 drain_workqueue+0x1a7/0x3c0 kernel/workqueue.c:2940 hci_dev_do_close+0x23a/0xf70 net/bluetooth/hci_core.c:1714 hci_power_on+0x1aa/0x610 net/bluetooth/hci_core.c:2211 process_one_work+0x94b/0x1690 kernel/workqueue.c:2264 worker_thread+0x96/0xe20 kernel/workqueue.c:2410 kthread+0x357/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352