INFO: task syz.5.1402:14826 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1402      state:D stack:26920 pid:14826 tgid:14826 ppid:14233  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
 f2fs_release_file+0xe3/0x150
 __fput+0x44c/0xa70
 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: 0033:0x7f5d4f98ebe9
RSP: 002b:00007ffe9ea07168 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f5d4fbb7da0 RCX: 00007f5d4f98ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f5d4fbb7da0 R08: 00000000000000e4 R09: 0000000c9ea0745f
R10: 00007f5d4fbb7cb0 R11: 0000000000000246 R12: 0000000000089973
R13: 00007ffe9ea07260 R14: ffffffffffffffff R15: 00007ffe9ea07280
 </TASK>
INFO: task syz.5.1402:14827 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1402      state:D stack:24648 pid:14827 tgid:14826 ppid:14233  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x9a/0x270
 wait_for_completion+0x2bf/0x5d0
 f2fs_issue_checkpoint+0x376/0x570
 f2fs_unlink+0x5eb/0xac0
 vfs_unlink+0x394/0x650
 do_unlinkat+0x345/0x560
 __x64_sys_unlinkat+0xd3/0xf0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5d4f98ebe9
RSP: 002b:00007f5d5079f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5d4fbb5fa0 RCX: 00007f5d4f98ebe9
RDX: 0000000000000000 RSI: 0000200000000c40 RDI: ffffffffffffff9c
RBP: 00007f5d4fa11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5d4fbb6038 R14: 00007f5d4fbb5fa0 R15: 00007ffe9ea07008
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u9:0/26:
 #0: ffff888100745148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900001efbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff8881244220e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
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/5676:
 #0: ffff888106e360a0 (&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
1 lock held by syz.5.1402/14826:
 #0: ffff88811f498a40 (&sb->s_type->i_mutex_key#24){++++}-{4:4}, at: f2fs_release_file+0xe3/0x150
3 locks held by syz.5.1402/14827:
 #0: ffff888124422428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff88811f49ae20 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: do_unlinkat+0x1c7/0x560
 #2: ffff88811f498a40 (&sb->s_type->i_mutex_key#24){++++}-{4:4}, at: vfs_unlink+0xf2/0x650
4 locks held by f2fs_ckpt-7:5/14840:
1 lock held by rm/16805:

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

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: 14840 Comm: f2fs_ckpt-7:5 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:kasan_check_range+0x5/0x2c0
Code: ba 8d e8 0e fb 04 ff 90 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d
RSP: 0018:ffffc90003f3f7d0 EFLAGS: 00000256
RAX: 00000000ffffff01 RBX: ffff888108678b88 RCX: ffffffff819dfff1
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90003f3f820
RBP: ffffc90003f3f890 R08: ffff888108678b8b R09: 1ffff110210cf171
R10: dffffc0000000000 R11: ffffed10210cf172 R12: ffff888108678b98
R13: ffff888108678b90 R14: 1ffff110210cf173 R15: 1ffff110210cf172
FS:  0000000000000000(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e63bcd7950 CR3: 0000000111d3c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 do_raw_spin_lock+0x121/0x290
 f2fs_write_checkpoint+0xab0/0x1df0
 __checkpoint_and_complete_reqs+0xd9/0x3b0
 issue_checkpoint_thread+0xd9/0x260
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
