INFO: task syz.8.904:14105 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.904       state:D stack:24264 pid:14105 tgid:14104 ppid:12036  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 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: 0033:0x7f5d34b9cdd9
RSP: 002b:00007f5d359d6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f5d34e15fa0 RCX: 00007f5d34b9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007f5d34c32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5d34e16038 R14: 00007f5d34e15fa0 R15: 00007ffe11725eb8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
7 locks held by kworker/u9:4/1110:
2 locks held by getty/5441:
 #0: ffff8881115b00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000346b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
2 locks held by syz-executor/9654:
1 lock held by syz.8.904/14105:
 #0: ffff8881bd6960d8 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.3.945/14426:
 #0: ffff8881bd6960d8 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x289/0x3d0
1 lock held by syz.7.964/14521:
 #0: ffff8881bd6960d8 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.1121/16017:
 #0: ffff8881bd6960d8 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz-executor/16297:
3 locks held by syz.0.1205/16669:
 #0: ffff88811cc5a410 (sb_writers#16){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881bb331dc0 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: btrfs_inode_lock+0x51/0xe0
 #2: ffff8881bb331c58 (&ei->i_mmap_lock){++++}-{4:4}, at: btrfs_inode_lock+0xcb/0xe0
1 lock held by syz.0.1205/16674:
 #0: ffff8881bb331dc0 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: process_measurement+0x451/0x1c80
5 locks held by syz.6.1206/16644:
1 lock held by udevadm/16675:

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

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+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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16675 Comm: udevadm 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:preempt_count_add+0x0/0x190
Code: 3c 24 e8 e3 39 9d 00 eb 8a e9 ed fe ff ff 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 41 57 41 56 53 49 bf 00 00 00 00 00 fc ff df 48 c7 c0
RSP: 0000:ffffc900046c79f0 EFLAGS: 00000246
RAX: 1ffffd4000885b15 RBX: ffff888110dc68a0 RCX: ffff888175d70000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000110b62067 R08: ffffffff821d0bf9 R09: ffffffff8e95cda0
R10: dffffc0000000000 R11: fffff9400088c171 R12: 1ffff11022f11df1
R13: ffff888110dc68a0 R14: dffffc0000000000 R15: ffffea0000000000
FS:  00007fa2ebd6cc80(0000) GS:ffff88818dc91000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005588fe2d3000 CR3: 0000000113af8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _raw_spin_lock+0x12/0x40
 pte_offset_map_lock+0x13d/0x210
 do_wp_page+0x3896/0x4cc0
 handle_mm_fault+0x151d/0x3170
 do_user_addr_fault+0xa73/0x1340
 exc_page_fault+0x6a/0xc0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7fa2ebe87d4e
Code: 00 00 75 ce eb 27 41 8b 45 08 48 8b 95 78 ff ff ff 49 03 55 00 48 83 f8 26 75 19 48 8b 85 78 ff ff ff 49 03 45 10 49 83 c5 18 <48> 89 02 4c 39 eb 77 d4 eb 9e 48 83 f8 08 74 e1 48 8d 0d 6b a7 01
RSP: 002b:00007ffeda0740b0 EFLAGS: 00010212
RAX: 00005588fe2c0f4a RBX: 00005588fe294f50 RCX: 00007ffeda074140
RDX: 00005588fe2d3000 RSI: 00005588fe2950d0 RDI: 00005588fe296558
RBP: 00007ffeda0741b0 R08: 00005588fe2950d0 R09: 00007fa2ebe71000
R10: 00007fa2ebe26a30 R11: 0000000000000206 R12: 00007fa2ebeab2a0
R13: 00005588fe291080 R14: 0000000000000000 R15: 00007fa2ebeab2a0
 </TASK>
