INFO: task syz.9.3545:13386 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.3545      state:D stack:27048 pid:13386 tgid:13385 ppid:11165  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17c4/0x4d60
 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/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3cd58efc9
RSP: 002b:00007fa3ce433038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fa3cd7e5fa0 RCX: 00007fa3cd58efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007fa3cd611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3cd7e6038 R14: 00007fa3cd7e5fa0 R15: 00007ffcc1f68c78
 </TASK>
INFO: task syz.9.3545:13387 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.3545      state:D stack:28104 pid:13387 tgid:13385 ppid:11165  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17c4/0x4d60
 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/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3cd58efc9
RSP: 002b:00007fa3ce412038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fa3cd7e6090 RCX: 00007fa3cd58efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007fa3cd611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3cd7e6128 R14: 00007fa3cd7e6090 R15: 00007ffcc1f68c78
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8df3d5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5643:
 #0: ffff88816ad4b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz-executor/8535:
2 locks held by syz-executor/9627:
6 locks held by kworker/u8:1/12149:
 #0: ffff888100ef7948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90005f4fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f2c6630 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820
 #3: ffff88810b7900e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0
 #4: ffff88810b795250 (&devlink->lock_key#56){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0
 #5: ffffffff8f2d3ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0
1 lock held by syz.9.3545/13386:
 #0: ffff88801df440e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.9.3545/13387:
 #0: ffff88801df440e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.3636/14166:
 #0: ffff88801df440e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
3 locks held by syz-executor/14471:
1 lock held by syz.6.3686/14701:
 #0: ffff88801df440e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.1.3766/16909:
 #0: ffff88801df440e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.3.3860/17959:
 #0: ffff888023c840e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.3.3860/17960:
 #0: ffff888023c840e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz-executor/19017:
 #0: ffffffff8df43038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
3 locks held by syz-executor/19415:
 #0: ffffffff8f2c6630 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0
 #1: ffffffff8f2d3ac8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990
 #2: ffffffff8df43038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
1 lock held by syz.8.3987/19462:
 #0: ffffffff8f2d3ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 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+0xfa9/0xff0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 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: 9627 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:check_preemption_disabled+0x5c/0x120
Code: 34 1f 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 <f7> 04 24 00 02 00 00 74 c8 65 4c 8b 3c 25 08 50 73 92 41 f6 47 2f
RSP: 0018:ffffc900082af680 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8d960304 RDI: ffffffff8bbf1fc0
RBP: 00000000ffffffff R08: ffff8881b8fbd2bb R09: 1ffff110371f7a57
R10: dffffc0000000000 R11: ffffed10371f7a58 R12: 0000000000000246
R13: ffff888111ef9d00 R14: ffffffff8df3d660 R15: 0000000000000002
FS:  000055558d75c500(0000) GS:ffff88818e8eb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffcd4ccad8 CR3: 000000010b7d6000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_is_held_type+0xfe/0x190
 __might_resched+0xf5/0x610
 down_write+0x76/0x1f0
 f2fs_write_checkpoint+0x55f/0x2440
 kill_f2fs_super+0x2cc/0x6d0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xe9/0x130
 do_syscall_64+0x2bd/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f65213902f7
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:00007ffed216afe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f65213902f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffed216b0a0
RBP: 00007ffed216b0a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffed216c130
R13: 00007f6521411d7d R14: 000000000009a678 R15: 00007ffed216c170
 </TASK>
