INFO: task syz.0.406:8501 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.406       state:D stack:25128 pid:8501  tgid:8500  ppid:5844   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: 0033:0x7f0af7b8ebe9
RSP: 002b:00007f0af8927038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f0af7dc5fa0 RCX: 00007f0af7b8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007f0af7c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0af7dc6038 R14: 00007f0af7dc5fa0 R15: 00007ffe326a67a8
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
 #0: ffff8880232b5948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90000107bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390
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/5673:
 #0: ffff8880291700a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900025682f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by kworker/u8:2/5742:
 #0: ffff8880232b5948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000313fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f538c48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0
4 locks held by syz-executor/5845:
1 lock held by syz.0.406/8501:
 #0: ffff88810f3920e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz-executor/9126:
 #0: ffff888129cc20e0 (&type->s_umount_key#61){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8e56e2e8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
1 lock held by syz.3.595/10014:
 #0: ffff88810f3920e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.4.624/10455:
 #0: ffff88810f3920e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.657/10595:
 #0: ffff88810f3920e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x25c/0x3b0
3 locks held by syz-executor/11153:
 #0: ffffffff8f538c48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70
 #1: ffff8880323b8d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: do_setlink+0x388/0x41c0
 #2: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
1 lock held by syz.5.735/11237:
 #0: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
2 locks held by syz.0.736/11268:
1 lock held by rm/11275:

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

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: 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:its_return_thunk+0x0/0x10
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <c3> cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 6b c3 b6 f5 cc
RSP: 0018:ffffc90003b7f750 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 39b71df818e11a00
RDX: 0000000000000000 RSI: ffffffff8dba7696 RDI: ffffffff8be33880
RBP: 00000000ffffffff R08: ffff88802cbb5bb3 R09: 1ffff11005976b76
R10: dffffc0000000000 R11: ffffed1005976b77 R12: 0000000000000246
R13: ffff888022f00000 R14: ffffffff8e139fe0 R15: 0000000000000002
FS:  0000555562b48500(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f55cca3dd11 CR3: 0000000027db4000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_is_held_type+0xfe/0x190
 __might_resched+0xf5/0x610
 down_write+0x76/0x1f0
 f2fs_write_checkpoint+0x51c/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: 0033:0x7fb5a878ff17
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:00007ffc432550a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fb5a8811c05 RCX: 00007fb5a878ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc43255160
RBP: 00007ffc43255160 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc432561f0
R13: 00007fb5a8811c05 R14: 00000000000214b4 R15: 00007ffc43256230
 </TASK>
