INFO: task syz.5.774:10648 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.774       state:D stack:25608 pid:10648 tgid:10647 ppid:9680   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1854/0x4d60
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x98/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 ksys_sync+0xa0/0x170
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xf0/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3b17f9acb9
RSP: 002b:00007f3b18ecd028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f3b18215fa0 RCX: 00007f3b17f9acb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f3b18215fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3b18216038 R14: 00007f3b18215fa0 R15: 00007ffcd48cd848
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13e760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by udevd/5256:
 #0: ffff8881012c0988 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x5d0
 #1: ffff88812103a058 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #2: ffff88812103a058 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
2 locks held by getty/5636:
 #0: ffff8881112a10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000357b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45f/0x14a0
3 locks held by kworker/0:4/5849:
 #0: ffff888100075948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17d0
 #1: ffffc90004927ba0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17d0
 #2: ffff8881a4882240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0
3 locks held by syz-executor/7215:
1 lock held by syz.5.774/10648:
 #0: ffff88810be0e0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.931/12584:
 #0: ffff88810be0e0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by dhcpcd/14382:
 #0: ffff888118564408 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240
 #1: ffffffff8e1441f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3f2/0x7e0
4 locks held by dhcpcd-run-hook/14917:

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

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+0x1a9/0x280
 nmi_cpu_backtrace+0x3a9/0x3e0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf5b/0xfa0
 kthread+0x726/0x8b0
 ret_from_fork+0x4d3/0x870
 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: 14916 Comm: syz.1.1119 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:native_apic_msr_write+0x39/0x50
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 40 82 f2 09 cc 89 f6 31 d2 e9 f6 0a 5a 03 66 0f 1f 44 00
RSP: 0018:ffffc90000a08e50 EFLAGS: 00000046
RAX: 000000000000794e RBX: ffff88823c623900 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 000000000000794e RDI: 0000000000000838
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81af4ea5
R10: 0000000000000003 R11: ffffffff81719470 R12: 000000001000035a
R13: dffffc0000000000 R14: 000000000000794e R15: 0000000000000020
FS:  00007fe6946786c0(0000) GS:ffff8882a9d12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe6895ffe00 CR3: 000000010bdb8000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 lapic_next_event+0x11/0x20
 clockevents_program_event+0x1cf/0x360
 hrtimer_interrupt+0x620/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x400
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x174/0x350
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6c 64 f2 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000809f7d0 EFLAGS: 00000206
RAX: 3f71c26d960e0b00 RBX: 0000000000000000 RCX: 3f71c26d960e0b00
RDX: 0000000000000000 RSI: ffffffff8db9e876 RDI: ffffffff8bdef9e0
RBP: ffffffff8204fe5e R08: 0000000000000000 R09: ffffffff8204fe5e
R10: dffffc0000000000 R11: ffffed1035b4f37d R12: 0000000000000000
R13: ffff8881ada799f8 R14: 0000000000000001 R15: 0000000000000246
 _raw_spin_lock+0x2e/0x40
 shmem_alloc_and_add_folio+0xbce/0xf90
 shmem_get_folio_gfp+0x5a9/0x1670
 shmem_write_begin+0xf7/0x2b0
 generic_perform_write+0x2e2/0x8f0
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x61d/0xb90
 ksys_write+0x150/0x270
 do_syscall_64+0xf0/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe69375b58e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007fe694677da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe6946786c0 RCX: 00007fe69375b58e
RDX: 0000000000200000 RSI: 00007fe689400000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007fe694677ee0 R14: 00007fe694677ea0 R15: 00007fe689400000
 </TASK>
