INFO: task syz.2.1188:10026 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1188      state:D stack:25128 pid:10026 tgid:10025 ppid:5852   task_flags:0x400140 flags:0x00004006
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
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe87b58ebe9
RSP: 002b:00007fe87c495038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe87b7b5fa0 RCX: 00007fe87b58ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe87b7b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe87b7b6038 R14: 00007fe87b7b5fa0 R15: 00007ffdab9372c8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5672:
 #0: ffff888108df90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz-executor/5845:
1 lock held by syz.2.1188/10026:
 #0: ffff888120d5e0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.5.2094/13703:
 #0: ffff88801efb57e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x211/0x4d0
2 locks held by syz.5.2094/13707:
1 lock held by dhcpcd-run-hook/13712:

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

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: 5845 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_is_held_type+0x125/0x190
Code: 16 00 00 b8 ff ff ff ff 65 0f c1 05 35 34 27 07 83 f8 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c <41> f7 c4 00 02 00 00 74 01 fb 65 48 8b 05 f9 f3 26 07 48 3b 44 24
RSP: 0018:ffffc9000337f7f8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 282f43d01d457200
RDX: 0000000000000000 RSI: ffffffff8dba5bba RDI: ffffffff8be33300
RBP: 00000000ffffffff R08: ffff8881232b5bb3 R09: 1ffff11024656b76
R10: dffffc0000000000 R11: ffffed1024656b77 R12: 0000000000000246
R13: ffff88801f608000 R14: ffffffff8e139f60 R15: 0000000000000002
FS:  0000555558309500(0000) GS:ffff8880b861c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f124ddf5fc8 CR3: 00000000270b0000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __might_resched+0xf5/0x610
 f2fs_write_checkpoint+0x50d/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: 0033:0x7f0d1d58ff17
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:00007fff2f6e9ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f0d1d611c05 RCX: 00007f0d1d58ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff2f6e9da0
RBP: 00007fff2f6e9da0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff2f6eae30
R13: 00007f0d1d611c05 R14: 000000000002ddba R15: 00007fff2f6eae70
 </TASK>
