turning off the locking correctness validator.
CPU: 1 PID: 2998 Comm: syzkaller607485 Not tainted 4.14.0-rc7-next-20171103+ #38
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 look_up_lock_class kernel/locking/lockdep.c:686 [inline]
 register_lock_class+0x5f2/0x2c70 kernel/locking/lockdep.c:769
 __lock_acquire+0x203/0x4770 kernel/locking/lockdep.c:3387
 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004
 down_read_nested+0x9a/0x150 kernel/locking/rwsem.c:157
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:666 [inline]
 snd_seq_deliver_event+0x559/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:676 [inline]
 snd_seq_deliver_event+0x362/0x820 sound/core/seq/seq_clientmgr.c:811
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 dummy_input+0x2c4/0x400 sound/core/seq/seq_dummy.c:104
 snd_seq_deliver_single_event.constprop.11+0x2fb/0x940 sound/core/seq/seq_clientmgr.c:621
 snd_seq_deliver_event+0x176/0x820 sound/core/seq/seq_clientmgr.c:822
 snd_seq_kernel_client_dispatch+0x11e/0x150 sound/core/seq/seq_clientmgr.c:2317
 snd_seq_oss_dispatch sound/core/seq/oss/seq_oss_device.h:150 [inline]
 snd_seq_oss_midi_reset+0x44b/0x700 sound/core/seq/oss/seq_oss_midi.c:481
 snd_seq_oss_synth_reset+0x398/0x980 sound/core/seq/oss/seq_oss_synth.c:416
 snd_seq_oss_reset+0x6c/0x260 sound/core/seq/oss/seq_oss_init.c:448
 snd_seq_oss_release+0x71/0x120 sound/core/seq/oss/seq_oss_init.c:425
 odev_release+0x52/0x70 sound/core/seq/oss/seq_oss.c:153
 __fput+0x333/0x7f0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9b5/0x1ad0 kernel/exit.c:869
 do_group_exit+0x149/0x400 kernel/exit.c:972
 SYSC_exit_group kernel/exit.c:983 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:981
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x442c58
RSP: 002b:00007ffd7d3be888 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442c58
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 0000000000000086 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 000000