INFO: task syz.3.2898:27908 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2898      state:D stack:27368 pid:27908 tgid:27906 ppid:26466  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f77f859ce59
RSP: 002b:00007f77f67f6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f77f8815fa0 RCX: 00007f77f859ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007f77f8632d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f77f8816038 R14: 00007f77f8815fa0 R15: 00007ffc1cee4f98
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5433:
 #0: ffff88816def00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
1 lock held by kworker/u10:3/16379:
4 locks held by syz-executor/24729:
1 lock held by udevd/27212:
1 lock held by syz.3.2898/27908:
 #0: ffff88816cfd20d8 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz-executor/29109:
 #0: ffffffff8e963068 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 31139 Comm: syz.7.3380 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:page_table_check_set+0x28c/0x510
Code: 48 89 df be 04 00 00 00 e8 61 66 f4 ff 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 52 01 00 00 <44> 8b 2b 31 ff 44 89 ee e8 67 2a 89 ff 45 85 ed 0f 85 42 02 00 00
RSP: 0000:ffffc900072cfae8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888100d03378 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888100d03378
RBP: ffff888100d03330 R08: ffff888100d0337b R09: 1ffff110201a066f
R10: dffffc0000000000 R11: ffffed10201a0670 R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000001 R15: 00000000000133d7
FS:  00007f03d3f7d6c0(0000) GS:ffff8882a928d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03c9c84000 CR3: 0000000184d60000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 do_pte_missing+0x336b/0x33f0
 handle_mm_fault+0x1bd7/0x3170
 do_user_addr_fault+0xa73/0x1340
 exc_page_fault+0x6a/0xc0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f03d30541ce
Code: c1 49 39 4f 08 72 54 8d 4d ff 85 ed 74 3b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01
RSP: 002b:00007f03d3f7c470 EFLAGS: 00010206
RAX: 0000000000e84001 RBX: 00007f03d3f7c530 RCX: 000000000000007c
RDX: 0000000000000005 RSI: 0000000000000001 RDI: 00007f03d3f7c5d0
RBP: 0000000000000102 R08: 00007f03c8e00000 R09: 0000000000e84000
R10: 0000000000000000 R11: 00007f03d3f7c540 R12: 0000000000000001
R13: 00007f03d3252900 R14: 0000000000000000 R15: 00007f03d3f7c5d0
 </TASK>
