INFO: task syz.6.1064:15602 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1064      state:D stack:25128 pid:15602 tgid:15601 ppid:15300  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: 0033:0x7f755e38ebe9
RSP: 002b:00007f755f21e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f755e5b5fa0 RCX: 00007f755e38ebe9
RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000902
RBP: 00007f755e411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f755e5b6038 R14: 00007f755e5b5fa0 R15: 00007ffc9ac6ed18
 </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/5674:
 #0: ffff8881086d20a0 (&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
2 locks held by syz-executor/9029:
3 locks held by syz-executor/10277:
2 locks held by syz-executor/14178:
1 lock held by syz.6.1064/15602:
 #0: ffff8881113e60e0 (&type->s_umount_key#102){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by udevd/15978:
1 lock held by syz.5.1120/16265:
 #0: ffff8881103300e0 (&type->s_umount_key#102){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.8.1292/18118:
 #0: ffff8881077b60e0 (&type->s_umount_key#102){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
7 locks held by syz.1.1342/18800:
2 locks held by syz.6.1345/18812:
2 locks held by rm/18841:

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

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: 10277 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+0x18d/0x360
Code: 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 3b f4 02 11 48 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e 41 5f <5d> c3 cc cc cc cc cc 65 8b 05 25 34 03 11 85 c0 75 ce 65 8b 05 1a
RSP: 0018:ffffc90002ddf6a8 EFLAGS: 00000282
RAX: 2be92875de454a00 RBX: ffff8881136ee328 RCX: 2be92875de454a00
RDX: 0000000000000000 RSI: ffffffff8dba6cac RDI: ffffffff8be33680
RBP: ffffffff8241ff44 R08: 0000000000000000 R09: ffffffff8241ff44
R10: ffffc90002ddf740 R11: fffff520005bbf16 R12: dffffc0000000000
R13: ffff8881136ee328 R14: ffff8881136ee2a8 R15: ffffc90002ddf740
FS:  000055557a6d4500(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc25859ba8 CR3: 00000001159f0000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _raw_spin_lock+0x2e/0x40
 writeback_single_inode+0x34/0x6a0
 sync_inode_metadata+0xb9/0x110
 f2fs_write_checkpoint+0xb06/0x1df0
 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: 0033:0x7f5af8d8ff17
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:00007ffd7b7fee58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f5af8e11c05 RCX: 00007f5af8d8ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd7b7fef10
RBP: 00007ffd7b7fef10 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd7b7fffa0
R13: 00007f5af8e11c05 R14: 0000000000043be8 R15: 00007ffd7b7fffe0
 </TASK>
