INFO: task syz.8.2337:20557 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.2337      state:D stack:25128 pid:20557 tgid:20555 ppid:19791  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: 0033:0x7fdad758ebe9
RSP: 002b:00007fdad83f2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fdad77b5fa0 RCX: 00007fdad758ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007fdad7611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdad77b6038 R14: 00007fdad77b5fa0 R15: 00007ffde0f4b8a8
 </TASK>
INFO: task syz.0.2367:20694 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2367      state:D stack:25128 pid:20694 tgid:20693 ppid:12624  task_flags:0x400040 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
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d2938ebe9
RSP: 002b:00007f1d2a18c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f1d295b5fa0 RCX: 00007f1d2938ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f1d295b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d295b6038 R14: 00007f1d295b5fa0 R15: 00007fffe08863e8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5675:
 #0: ffff888021ecc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
4 locks held by syz-executor/18951:
1 lock held by syz.8.2337/20557:
 #0: ffff8880206ec0e0 (&type->s_umount_key#77){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.2367/20694:
 #0: ffff8880206ec0e0 (&type->s_umount_key#77){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.2761/23735:
 #0: ffff8880206ec0e0 (&type->s_umount_key#77){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
5 locks held by syz.6.2763/23751:
4 locks held by syz.9.2762/23764:

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

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+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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 23764 Comm: syz.9.2762 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:mark_lock+0x26/0x190
Code: 90 90 90 90 55 41 57 41 56 41 55 41 54 53 8b 46 20 89 c1 81 e1 00 00 03 00 83 f9 01 bb 09 00 00 00 83 db 00 83 fa 08 0f 45 da <bd> 01 00 00 00 89 d9 d3 e5 25 ff 1f 00 00 48 0f a3 05 c4 88 0a 12
RSP: 0018:ffffc90002c4f6b8 EFLAGS: 00000093
RAX: 0000000000040601 RBX: 0000000000000006 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffff888105e66158 RDI: ffff888105e65640
RBP: ffffc90002c4f870 R08: ffffffff8fa38a37 R09: 1ffffffff1f47146
R10: dffffc0000000000 R11: fffffbfff1f47147 R12: ffff888105e66180
R13: 00000003fffffffc R14: ffff888105e66158 R15: 0000000000000001
FS:  00007fecf020e6c0(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fece5fff000 CR3: 0000000114622000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lockdep_hardirqs_on_prepare+0x191/0x2a0
 trace_hardirqs_on+0x28/0x40
 _raw_spin_unlock_irq+0x23/0x50
 shmem_add_to_page_cache+0x8ee/0xba0
 shmem_alloc_and_add_folio+0x846/0xf60
 shmem_get_folio_gfp+0x59d/0x1660
 shmem_write_begin+0xf7/0x2b0
 generic_perform_write+0x2c5/0x900
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fecef38d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fecf020ddf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fecef38d69f
RDX: 0000000001000000 RSI: 00007fece5000000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000981f
R10: 000020000001c902 R11: 0000000000000293 R12: 0000000000000006
R13: 00007fecf020def0 R14: 00007fecf020deb0 R15: 00007fece5000000
 </TASK>
