INFO: task syz.6.294:8531 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.294       state:D stack:25856 pid:8531  tgid:8529  ppid:8295   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 drop_caches_sysctl_handler+0x97/0x170
 proc_sys_call_handler+0x4c8/0x830
 do_iter_readv_writev+0x619/0x8c0
 vfs_writev+0x33c/0x990
 do_writev+0x154/0x2e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb2af19c799
RSP: 002b:00007fb2b0098028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fb2af415fa0 RCX: 00007fb2af19c799
RDX: 0000000000000001 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007fb2af232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb2af416038 R14: 00007fb2af415fa0 R15: 00007ffc191202a8
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/10:
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5632:
 #0: ffff8881747cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by syz-executor/6280:
5 locks held by kworker/u8:5/6299:
3 locks held by kworker/0:6/6580:
3 locks held by kworker/0:9/7004:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc90003f07c40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8e7647b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
3 locks held by syz.6.294/8531:
 #0: ffff88811257a2f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff888112964420 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2aa/0x990
 #2: ffff8881bb87a0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.9.404/9594:
 #0: ffff8881bb87a0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.9.404/9599:
 #0: ffff8881bb87a0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.3.516/10444:
 #0: ffff8881bb87a0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by dhcpcd/13332:
 #0: ffff8881bae55008 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240
1 lock held by syz-executor/13787:
 #0: ffffffff8e7647b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by syz-executor/14249:
1 lock held by syz.8.970/14306:

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 6280 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:kasan_check_range+0x59/0x2c0
Code: ff eb 0d cc cc cc 49 b9 00 00 00 00 00 00 00 ff 4c 39 cf 0f 82 14 02 00 00 49 89 ff 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df <4f> 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc
RSP: 0018:ffffc9000739f808 EFLAGS: 00000a07
RAX: 0000000080000001 RBX: ffff888174968bb0 RCX: ffffffff8431e125
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88817496915c
RBP: ffffc9000739fbb0 R08: ffff888174969160 R09: ffff800000000000
R10: dffffc0000000000 R11: ffffed102e92d071 R12: ffff88817496915c
R13: dffffc0000000000 R14: 0000000000000001 R15: 1ffff1102e92d22b
FS:  00005555928ff500(0000) GS:ffff88818de60000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffce93890c8 CR3: 0000000168a8c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 f2fs_write_checkpoint+0xa75/0x26a0
 kill_f2fs_super+0x314/0x720
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f41e2f9d9d7
Code: a2 c7 05 1c fd 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 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 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdfda3cc58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f41e3032050 RCX: 00007f41e2f9d9d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdfda3cd10
RBP: 00007ffdfda3cd10 R08: 00007ffdfda3dd10 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdfda3dda0
R13: 00007f41e3032050 R14: 0000000000013d43 R15: 00007ffdfda3dde0
 </TASK>
