WARNING in __lock

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
android-44	WARNING in __lock_acquire	C			3	2316d	1838d	0/2	public: reported C repro on 2019/04/13 00:00
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WARNING: CPU: 0 PID: 15302 at kernel/locking/lockdep.c:3322 __lock_acquire+0x1768/0x3640 kernel/locking/lockdep.c:3322
DEBUG_LOCKS_WARN_ON(class_idx > MAX_LOCKDEP_KEYS)[  102.244536] Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 15302 Comm: syz-executor2 Not tainted 4.9.61-ga93e312 #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
binder_alloc: binder_alloc_mmap_handler: 15301 20000000-20400000 already mapped failed -16
 ffff8801c82bf4a8 ffffffff81d91589 ffffffff83a46ba0 ffff8801c82bf580
 ffffffff83a5a300 ffffffff8123d238 0000000000000009 ffff8801c82bf570
 ffffffff8142e391 0000000041b58ab3 ffffffff84185db0 ffffffff8142e1d5
Call Trace:
 [<ffffffff81d91589>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d91589>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8142e391>] panic+0x1bc/0x3a8 kernel/panic.c:179
 [<ffffffff811321e4>] __warn+0x1c4/0x1e0 kernel/panic.c:542
 [<ffffffff811322c4>] warn_slowpath_fmt+0xc4/0x110 kernel/panic.c:565
 [<ffffffff8123d238>] __lock_acquire+0x1768/0x3640 kernel/locking/lockdep.c:3322
 [<ffffffff8123fb4e>] lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756
 [<ffffffff838a9d72>] __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline]
 [<ffffffff838a9d72>] _raw_write_lock_irq+0x42/0x60 kernel/locking/spinlock.c:311
 [<ffffffff82e18200>] delete_and_unsubscribe_port+0x60/0x3a0 sound/core/seq/seq_ports.c:547
 [<ffffffff82e1ace7>] snd_seq_port_disconnect+0x1b7/0x230 sound/core/seq/seq_ports.c:630
 [<ffffffff82e0c912>] snd_seq_ioctl_unsubscribe_port+0x212/0x2c0 sound/core/seq/seq_clientmgr.c:1488
 [<ffffffff82e02662>] snd_seq_kernel_client_ctl+0x122/0x160 sound/core/seq/seq_clientmgr.c:2349
 [<ffffffff82e2c893>] snd_seq_oss_midi_close+0x363/0x590 sound/core/seq/oss/seq_oss_midi.c:416
 [<ffffffff82e2943b>] snd_seq_oss_synth_reset+0x3cb/0x8b0 sound/core/seq/oss/seq_oss_synth.c:418
 [<ffffffff82e1fe8c>] snd_seq_oss_reset+0x6c/0x260 sound/core/seq/oss/seq_oss_init.c:448
 [<ffffffff82e200f1>] snd_seq_oss_release+0x71/0x130 sound/core/seq/oss/seq_oss_init.c:425
 [<ffffffff82e1e892>] odev_release+0x52/0x70 sound/core/seq/oss/seq_oss.c:153
 [<ffffffff815734dc>] __fput+0x28c/0x6e0 fs/file_table.c:208
 [<ffffffff815739b5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff81196005>] task_work_run+0x115/0x190 kernel/task_work.c:116
 [<ffffffff8113d2e7>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff8113d2e7>] do_exit+0x7e7/0x2a40 kernel/exit.c:833
 [<ffffffff811439f8>] do_group_exit+0x108/0x320 kernel/exit.c:937
 [<ffffffff81143c2d>] SYSC_exit_group kernel/exit.c:948 [inline]
 [<ffffffff81143c2d>] SyS_exit_group+0x1d/0x20 kernel/exit.c:946
 [<ffffffff838aa305>] entry_SYSCALL_64_fastpath+0x23/0xc6
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..