bisecting fixing commit since 6fbc7275c7a9ba97877050335f290341a1fd8dbf
building syzkaller on 907bf74686129436f81aa40336ee89f7cc01b0b4
testing commit 6fbc7275c7a9ba97877050335f290341a1fd8dbf with gcc (GCC) 8.1.0
kernel signature: 5fe81bc5b11a377778a4dc2d1dded037cd1d3c8d
run #0: crashed: WARNING in kernfs_get
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: refcount bug in hci_register_dev
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: general protection fault in idr_remove
run #9: crashed: WARNING in kernfs_get
testing current HEAD 4a3033ef6e6bb4c566bd1d556de69b494d76976c
testing commit 4a3033ef6e6bb4c566bd1d556de69b494d76976c with gcc (GCC) 8.1.0
kernel signature: da06da659d06018265cc0bacc41e6c8452c02ee3
all runs: crashed: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
revisions tested: 2, total time: 19m59.801178926s (build: 11m27.622955925s, test: 8m6.013361564s)
the crash still happens on HEAD
commit msg: Merge tag 'gpio-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
crash: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
turning off the locking correctness validator.
CPU: 0 PID: 1527 Comm: kworker/u5:0 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci3 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:2841 [inline]
 lookup_chain_cache_add kernel/locking/lockdep.c:2915 [inline]
 validate_chain kernel/locking/lockdep.c:2936 [inline]
 __lock_acquire.cold.65+0x18/0x385 kernel/locking/lockdep.c:3955
 lock_acquire+0x194/0x410 kernel/locking/lockdep.c:4485
 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
 _raw_read_lock+0x30/0x40 kernel/locking/spinlock.c:223
 hci_leds_update_powered+0x7c/0x160 net/bluetooth/leds.c:30
 hci_dev_do_close+0x108/0xe30 net/bluetooth/hci_core.c:1687
 hci_power_on+0x163/0x4d0 net/bluetooth/hci_core.c:2211
 process_one_work+0x856/0x1630 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