INFO: task poweroff:8835 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:poweroff        state:D stack:24008 pid:8835  tgid:8835  ppid:5247   task_flags:0x400000 flags:0x00080001
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/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36be79d7e7
RSP: 002b:00007ffedb9bc578 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f36be79d7e7
RDX: 0000000000000078 RSI: 00007f36be92c8ca RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000001 R09: 00007f36be92c8ca
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffedb9bc6c8
R13: 00007ffedb9bc6d8 R14: 00005646fac87169 R15: 00007f36be97da80
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8df3d620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u10:9/1207:
2 locks held by getty/5642:
 #0: ffff88816b9970a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000357b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz-executor/5816:
1 lock held by poweroff/8835:
 #0: ffff88816f0740e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.8.713/9781:
 #0: ffff88816f0740e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.871/10424:
 #0: ffff88816f0740e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x25c/0x3b0
1 lock held by syz-executor/11547:
2 locks held by syz.7.1139/12105:

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

NMI backtrace for cpu 0
CPU: 0 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 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: 7808 Comm: udevd 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:unwind_next_frame+0x130a/0x2390
Code: c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 48
RSP: 0018:ffffc9000713f758 EFLAGS: 00000a07
RAX: 1ffffffff1f3318d RBX: ffffffff8f998c6c RCX: dffffc0000000000
RDX: ffffffff8f998c6c RSI: ffffffff90187cb2 RDI: ffffffff8bbf1280
RBP: ffffffff8f998c6c R08: 0000000000000009 R09: ffffffff81739d25
R10: ffffc9000713f878 R11: ffffffff81ac4220 R12: ffffffff82262456
R13: ffffffff8f998c6c R14: ffffc9000713f828 R15: ffffffff8f998c6c
FS:  00007f70906f3c80(0000) GS:ffff8882a9f32000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc2335b4198 CR3: 0000000172ce0000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 save_stack+0xf5/0x1f0
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbc8/0xd30
 __put_partials+0x146/0x170
 put_cpu_partial+0x1f2/0x2e0
 __slab_free+0x2b9/0x390
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x37d/0x700
 getname_flags+0xb8/0x540
 do_sys_openat2+0xbc/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f70903169a4
Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffff25d6100 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000564c0f397bd0 RCX: 00007f70903169a4
RDX: 0000000000080000 RSI: 0000564c0f2125a0 RDI: 00000000ffffff9c
RBP: 0000564c0f2125a0 R08: 0000564c0f2125a0 R09: 00007f70903f1b10
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000
R13: 0000000000000709 R14: 0000000000000000 R15: 0000000000000001
 </TASK>
