INFO: task syz-executor:5853 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21832 pid:5853  tgid:5853  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 __writeback_inodes_sb_nr+0x1f6/0x250
 sync_filesystem+0xa3/0x230
 generic_shutdown_super+0x6f/0x2c0
 bch2_kill_sb+0x41/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f494c18ff17
RSP: 002b:00007ffcb0818878 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f494c211c05 RCX: 00007f494c18ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcb0818930
RBP: 00007ffcb0818930 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcb08199c0
R13: 00007f494c211c05 R14: 000000000000eb26 R15: 00007ffcb0819a00
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:0H/11:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u9:4/4302:
 #0: ffff88801afd5148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900097d7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
2 locks held by getty/5675:
 #0: ffff88810925a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz-executor/5853:
 #0: ffff8881195da0e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0
1 lock held by syz.2.650/9313:
 #0: ffff8881195da0e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: super_lock+0x25c/0x3b0
2 locks held by rm/9475:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9467 Comm: syz.3.668 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:lock_is_held_type+0x68/0x190
Code: 00 00 65 4c 8b 2c 25 08 b0 a0 92 41 83 bd ec 0a 00 00 00 0f 85 d8 00 00 00 89 f5 49 89 fe 48 c7 04 24 00 00 00 00 9c 8f 04 24 <4c> 8b 24 24 fa 48 c7 c7 41 ce 9c 8d e8 17 17 00 00 65 ff 05 c0 c4
RSP: 0018:ffffc900065cf670 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 1ffff11009607501
RDX: ffffc90002ff1000 RSI: 00000000ffffffff RDI: ffff88804b039f98
RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000cb9ec8 R12: dffffc0000000000
R13: ffff88812594d640 R14: ffff88804b039f98 R15: ffff88804b03ab58
FS:  00007f98385e36c0(0000) GS:ffff8880b8615000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000225c CR3: 000000010d038000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 update_rq_clock+0x8f/0x5b0
 __schedule+0x473/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 snd_rawmidi_write+0x3a8/0xbd0
 vfs_writev+0x4b6/0x960
 do_writev+0x14d/0x2d0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f983778ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f98385e3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f98379c5fa0 RCX: 00007f983778ebe9
RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000005
RBP: 00007f9837811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98379c6038 R14: 00007f98379c5fa0 R15: 00007fff1723a578
 </TASK>
vkms_vblank_simulate: vblank timer overrun
