INFO: task syz.7.1881:16098 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1881      state:D stack:25128 pid:16098 tgid:16097 ppid:13396  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
 __iterate_supers+0x126/0x290
 __se_sys_quotactl+0x353/0x950
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a4178ebe9
RSP: 002b:00007f8a425d0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f8a419c5fa0 RCX: 00007f8a4178ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007f8a41811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8a419c6038 R14: 00007f8a419c5fa0 R15: 00007ffc46a68f28
 </TASK>

Showing all locks held in the system:
1 lock held by ksoftirqd/0/15:
 #0: ffff88804b039f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5676:
 #0: ffff8881089ad0a0 (&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
6 locks held by kworker/1:4/5896:
 #0: ffff88801b70f948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900036afbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888023bbe198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff888023be1518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20
 #4: ffff888020c83c68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20
 #5: ffffffff8ede0950 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750
3 locks held by syz-executor/14799:
1 lock held by syz.7.1881/16098:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17083:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17090:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17091:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17093:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17097:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2007/17102:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.2025/17172:
 #0: ffff8881243f00e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0

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

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: 14799 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:__sanitizer_cov_trace_const_cmp4+0x37/0x90
Code: 08 80 a0 92 65 8b 0d c8 cd e0 10 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 3c 16 00 00 00 74 52 8b 8a 18 16 00 00 <83> f9 03 75 47 48 8b 8a 20 16 00 00 44 8b 8a 1c 16 00 00 49 c1 e1
RSP: 0018:ffffc900030cf668 EFLAGS: 00000246
RAX: ffffffff8241e1eb RBX: ffff88811a04b650 RCX: 0000000000000000
RDX: ffff88801f971cc0 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000619ec8 R12: 1ffff110234096ee
R13: ffff88811a04b770 R14: 1ffffffff1f4782c R15: dffffc0000000000
FS:  00005555925ac500(0000) GS:ffff8880b8618000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31c18ff8 CR3: 000000011571a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 locked_inode_to_wb_and_lock_list+0x8b/0x300
 writeback_single_inode+0x20d/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: 0033:0x7f8c5b98ff17
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:00007ffdc1dd8c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f8c5ba11c05 RCX: 00007f8c5b98ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdc1dd8d10
RBP: 00007ffdc1dd8d10 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdc1dd9da0
R13: 00007f8c5ba11c05 R14: 0000000000076f29 R15: 00007ffdc1dd9de0
 </TASK>
