INFO: task syz.7.219:7431 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.219       state:D stack:24696 pid:7431  tgid:7430  ppid:6994   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: 0033:0x7ff734f9cdd9
RSP: 002b:00007ff735f2e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007ff735215fa0 RCX: 00007ff734f9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007ff735032d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff735216038 R14: 00007ff735215fa0 R15: 00007ffdd09ea338
 </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
5 locks held by kworker/u9:3/82:
 #0: ffff88812103aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150
 #1: ffff888121024588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffff888121026118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30
 #3: ffffffff9a6c5630 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580
 #4: ffff888121024588 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xd4/0x340
2 locks held by getty/5438:
 #0: ffff8881169b40a0 (&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
2 locks held by syz-executor/6524:
1 lock held by syz.7.219/7431:
 #0: ffff8881b00460d8 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz-executor/8786:
 #0: ffff8881a2d8e0d8 (&type->s_umount_key#62){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
4 locks held by syz.0.603/10939:

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

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+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: 10939 Comm: syz.0.603 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:__lock_acquire+0x1878/0x2cf0
Code: 80 e2 fa 80 78 2b 00 0f b6 c2 0f 44 c1 84 c0 0f 84 3d ff ff ff a8 0c 41 0f 94 44 24 2b 4d 8b 6c 24 10 41 0f b6 85 c6 00 00 00 <85> c0 74 5f 83 f8 01 0f 85 1b ff ff ff 83 3d a4 a8 a2 18 00 0f 85
RSP: 0018:ffffc90003e6f400 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 00000000000003fd RCX: 0000000000000008
RDX: 0000000000000008 RSI: ffff88810f578c80 RDI: 00000000000003fd
RBP: 83acc58353bc121e R08: ffffc90003e6f3c8 R09: 0000000000000020
R10: 0000000000000003 R11: ffffffff81a21d20 R12: ffffffff96c5eb88
R13: ffffffff93e33810 R14: ffff88810f578000 R15: 00000000000004b9
FS:  00007f7268ff66c0(0000) GS:ffff88818dc8f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34e14ff8 CR3: 00000001a0ddc000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350
 seqcount_lockdep_reader_access+0x55/0x100
 ktime_get+0x45/0x220
 clockevents_program_event+0x290/0x630
 hrtimer_start_range_ns+0xb09/0xed0
 finish_task_switch+0x3cd/0xbe0
 __schedule+0x17bc/0x5680
 preempt_schedule_irq+0x4d/0xa0
 irqentry_exit+0x14f/0x730
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x221/0x350
Code: ff ff ff e8 51 04 07 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b 5f 97 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c8 60 92
RSP: 0018:ffffc90003e6fb60 EFLAGS: 00000286
RAX: c3379c0de9727b00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8e2199bc RDI: ffffffff8c28aee0
RBP: ffffffff8222e95c R08: ffffc90003e6f980 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a21d20 R12: 0000000000000000
R13: ffffffff8ea9a120 R14: 0000000000000001 R15: 0000000000000246
 fs_reclaim_acquire+0x98/0x100
 __kmalloc_cache_noprof+0x40/0x660
 get_mountpoint+0x2cc/0x510
 do_lock_mount+0x56a/0x960
 do_loopback+0x286/0x6c0
 __se_sys_mount+0x31d/0x420
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f726ad9cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7268ff6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f726b015fa0 RCX: 00007f726ad9cdd9
RDX: 0000000000000000 RSI: 0000200000000140 RDI: 00002000000000c0
RBP: 00007f726ae32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000003801000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f726b016038 R14: 00007f726b015fa0 R15: 00007ffe3e5bc8e8
 </TASK>
