INFO: task syz.1.237:8341 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.237       state:D stack:26200 pid:8341  tgid:8339  ppid:7792   task_flags:0x400140 flags:0x00004004
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/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c8fd8ebe9
RSP: 002b:00007f7c90b8b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f7c8ffb5fa0 RCX: 00007f7c8fd8ebe9
RDX: 000000000000ee00 RSI: 0000200000000240 RDI: ffffffff80000800
RBP: 00007f7c8fe11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000080 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7c8ffb6038 R14: 00007f7c8ffb5fa0 R15: 00007fffeedb7388
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5672:
 #0: ffff8881096ef0a0 (&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
3 locks held by syz-executor/5843:
3 locks held by syz-executor/6877:
3 locks held by syz-executor/7808:
1 lock held by syz.1.237/8341:
 #0: ffff88802eed40e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz.7.269/8915:
 #0: ffff888116a26428 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160
 #1: ffff88802eed40e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.8.367/9992:
 #0: ffff8880343a00e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.3.397/10114:
 #0: ffff8880340080e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz.1.467/10585:
2 locks held by syz.4.468/10601:
 #0: ffff8881061d6428 (sb_writers#33){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160
 #1: 
ffff888115f7c260 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: generic_file_write_iter+0xeb/0x550

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

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+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 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: 6877 Comm: syz-executor 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_acquire+0xad3/0xd20
Code: 01 00 00 4c 89 f6 89 ea 4c 89 f9 e8 17 38 00 00 85 c0 0f 84 e4 01 00 00 41 f6 46 22 10 75 2e 48 8b 1c 24 4c 89 bb e0 0a 00 00 <8b> 83 e8 0a 00 00 ff c0 89 83 e8 0a 00 00 83 f8 30 0f 83 64 01 00
RSP: 0018:ffffc9000390f820 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff888022b89cc0 RCX: ae8ec9d905a7b400
RDX: 0000000000000000 RSI: ffff888022b8a800 RDI: ffff888022b89cc0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8409d560
R10: dffffc0000000000 R11: ffffed1006ab3a0f R12: 0000000002021d70
R13: ffff888022b8a7b0 R14: ffff888022b8a800 R15: bdf4580c621cbdf0
FS:  000055557b24b500(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff207fee8 CR3: 000000012825e000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x120/0x360
 _raw_spin_lock+0x2e/0x40
 f2fs_write_checkpoint+0xab0/0x1df0
 kill_f2fs_super+0x2c3/0x6c0
 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: 0033:0x7f3c45b8ff17
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd277dc1a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3c45c11c05 RCX: 00007f3c45b8ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd277dc260
RBP: 00007ffd277dc260 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd277dd2f0
R13: 00007f3c45c11c05 R14: 0000000000022b6f R15: 00007ffd277dd330
 </TASK>
