INFO: task syz.3.936:10194 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.936       state:D stack:26440 pid:10194 tgid:10192 ppid:9773   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x4da/0x950
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd01c78eec9
RSP: 002b:00007fd01d5d4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fd01c9e6090 RCX: 00007fd01c78eec9
RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000901
RBP: 00007fd01c811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd01c9e6128 R14: 00007fd01c9e6090 R15: 00007ffeba59c7a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5638:
 #0: ffff888112ec80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz.3.206/6767:
1 lock held by syz.3.936/10194:
 #0: ffff8881a5d1a0e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0

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

NMI backtrace for cpu 0
CPU: 0 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+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6767 Comm: syz.3.206 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:__might_resched+0x5/0x610
Code: ee e9 48 ff ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 00
RSP: 0018:ffffc90003d574d0 EFLAGS: 00000246
RAX: ffffffff840faa0a RBX: ffff888168310b50 RCX: ffff88817478d700
RDX: 0000000000000000 RSI: 00000000000004f2 RDI: ffffffff8bb31660
RBP: ffffc90003d57830 R08: ffff8881aa4d64ab R09: 1ffff1103549ac95
R10: dffffc0000000000 R11: ffffed103549ac96 R12: ffff8881aa4d62a8
R13: dffffc0000000000 R14: ffffffffffffffff R15: dffffc0000000000
FS:  00007fa86ddaf6c0(0000) GS:ffff8882a9d0c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011bca2000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 f2fs_write_checkpoint+0x548/0x2440
 kill_f2fs_super+0x2cc/0x6d0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1285/0x1340
 arch_do_signal_or_restart+0xa0/0x790
 exit_to_user_mode_loop+0x72/0x130
 do_syscall_64+0x2bd/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86cfc1785
Code: Unable to access opcode bytes at 0x7fa86cfc175b.
RSP: 002b:00007fa86ddaef80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fa86d1e5fa0 RCX: 00007fa86cfc1785
RDX: 00007fa86ddaefc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa86d011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fa86d1e6038 R14: 00007fa86d1e5fa0 R15: 00007ffe4247ceb8
 </TASK>
