bisecting fixing commit since 1e78030e5e5b2d8b0cad7136caf9cfab986a6bff
building syzkaller on 835dffe7e5d185154a9b147476a17b6301ee139e
testing commit 1e78030e5e5b2d8b0cad7136caf9cfab986a6bff with gcc (GCC) 8.1.0
kernel signature: 31ea69bb070d00a016ab7e0da138e37894539b1d87227533707568ef45b5f076
run #0: crashed: WARNING in dpm_sysfs_add
run #1: crashed: general protection fault in kernfs_add_one
run #2: crashed: WARNING in kernfs_get
run #3: crashed: WARNING in kernfs_get
run #4: crashed: WARNING in kernfs_get
run #5: crashed: general protection fault in kernfs_add_one
run #6: crashed: WARNING: refcount bug in hci_register_dev
run #7: crashed: WARNING in kernfs_get
run #8: crashed: WARNING in kernfs_get
run #9: crashed: WARNING in kernfs_get
testing current HEAD fdfa3a6778b194974df77b384cc71eb2e503639a
testing commit fdfa3a6778b194974df77b384cc71eb2e503639a with gcc (GCC) 8.1.0
kernel signature: 645da1c40b6becc593b5cdf77b8cb5d4e8f6e99fdccf349cfe51aaa2263aa973
all runs: crashed: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
revisions tested: 2, total time: 22m52.384193285s (build: 12m43.721421865s, test: 9m19.637871643s)
the crash still happens on HEAD
commit msg: Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
crash: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
turning off the locking correctness validator.
CPU: 0 PID: 8180 Comm: kworker/u5:1 Not tainted 5.5.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci2 hci_power_on
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x12d/0x187 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.65+0x18/0x385 kernel/locking/lockdep.c:3954
 lock_acquire+0x194/0x410 kernel/locking/lockdep.c:4484
 __mutex_lock_common kernel/locking/mutex.c:956 [inline]
 __mutex_lock+0x155/0x1410 kernel/locking/mutex.c:1103
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118
 drain_workqueue+0x22/0x340 kernel/workqueue.c:2935
 hci_dev_do_close+0x1d8/0xe30 net/bluetooth/hci_core.c:1714
 hci_power_on+0x163/0x4d0 net/bluetooth/hci_core.c:2211
 process_one_work+0x88b/0x1680 kernel/workqueue.c:2264
 worker_thread+0x85/0xb60 kernel/workqueue.c:2410
 kthread+0x331/0x3f0 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352