INFO: task syz.6.564:9782 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.564       state:D stack:25128 pid:9782  tgid:9781  ppid:9562   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write+0x1ab/0x1f0
 super_lock+0x25c/0x3b0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x4da/0x950
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0fcab8ec29
RSP: 002b:00007f0fcba84038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f0fcadd5fa0 RCX: 00007f0fcab8ec29
RDX: 0000000000000000 RSI: 0000200000000080 RDI: ffffffff80000201
RBP: 00007f0fcac11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0fcadd6038 R14: 00007f0fcadd5fa0 R15: 00007fffa2cb99f8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5677:
 #0: ffff888028ee10a0 (&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/6774:
1 lock held by syz.6.564/9782:
 #0: ffff888110eee0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x25c/0x3b0
1 lock held by syz.1.765/11786:
 #0: ffff888110eee0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.6.831/12429:
 #0: ffff888110eee0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz-executor/12758:
 #0: ffff888020e760e0 (&type->s_umount_key#64){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8e13fa40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570
1 lock held by syz.5.874/13059:
 #0: ffff888110eee0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.5.874/13060:
 #0: ffff888110eee0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz.0.877/13179:
2 locks held by dhcpcd/13235:
 #0: ffff88812bb4e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0
 #1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
2 locks held by dhcpcd/13236:
 #0: ffff88802aec8258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0
 #1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730

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

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+0x439/0x7d0
 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: 6774 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+0x6cf/0xd20
Code: 25 00 00 45 31 ff 85 c0 0f 84 f5 05 00 00 83 3d 36 cb 0e 18 00 75 13 48 63 44 24 20 48 0f a3 05 a7 3b 0b 12 0f 83 15 05 00 00 <31> ed 48 8b 3c 24 4c 8b bf e0 0a 00 00 48 83 7c 24 28 00 75 1e 83
RSP: 0018:ffffc90006647590 EFLAGS: 00000047
RAX: 00000000000008b9 RBX: ffff888020b8b980 RCX: ffffffff93507398
RDX: 0000000000000008 RSI: ffff888020b8c4c0 RDI: ffff888020b8b980
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff82421374
R10: ffffc90006647740 R11: fffff52000cc8f16 R12: 0000000000000004
R13: 0000000000000003 R14: ffff888020b8c4c0 R15: 0000000000000000
FS:  0000555565b8d500(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe9b56f5c8 CR3: 000000003bfc0000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x120/0x360
 _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: 0033:0x7f3a3bb8ff57
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:00007ffc58b2a578 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3a3bc11c2d RCX: 00007f3a3bb8ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc58b2a630
RBP: 00007ffc58b2a630 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc58b2b6c0
R13: 00007f3a3bc11c2d R14: 000000000001dceb R15: 00007ffc58b2b700
 </TASK>
