INFO: task syz-executor.1:6041 blocked for more than 143 seconds.
      Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:28720 pid:6041  tgid:6041  ppid:6033   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6778
 schedule_timeout+0x257/0x290 kernel/time/timer.c:2143
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common+0x3e0/0x5f0 kernel/sched/completion.c:116
 vhost_worker_flush+0xc5/0x100 drivers/vhost/vhost.c:293
 vhost_dev_flush+0xaa/0x180 drivers/vhost/vhost.c:307
 vhost_vsock_flush drivers/vhost/vsock.c:693 [inline]
 vhost_vsock_dev_release+0x1a5/0x3f0 drivers/vhost/vsock.c:745
 __fput+0x270/0xbb0 fs/file_table.c:394
 task_work_run+0x14d/0x240 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa92/0x2ae0 kernel/exit.c:871
 __do_sys_exit kernel/exit.c:988 [inline]
 __se_sys_exit kernel/exit.c:986 [inline]
 __x64_sys_exit+0x42/0x50 kernel/exit.c:986
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f014067cba9
RSP: 002b:0000000020000198 EFLAGS: 00000246 ORIG_RAX: 000000000000003c
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007f014067cba9
RDX: 00007f014067cba9 RSI: 00000000200001c0 RDI: 000000000000000b
RBP: 00007f01406c847a R08: 0000000000000058 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f014079c050 R15: 00007ffeaa26de28
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/28:
 #0: ffffffff8cfa82e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline]
 #0: ffffffff8cfa82e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8cfa82e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614
2 locks held by getty/4818:
 #0: ffff8880283180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900020382f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201
2 locks held by vhost-6033/6035:
1 lock held by syz-executor.1/6041:
 #0: ffff88807c876370 (&worker->mutex){+.+.}-{3:3}, at: vhost_dev_flush+0xeb/0x180 drivers/vhost/vhost.c:302
3 locks held by kworker/u4:21/6097:

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x277/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf87/0x1210 kernel/hung_task.c:379
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6035 Comm: vhost-6033 Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0x0/0x16
Code: 56 57 41 50 41 51 41 52 41 53 e8 7b 16 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <f3> 0f 1e fa 52 b8 01 00 00 00 31 d2 f0 0f b0 17 3c 01 75 02 5a c3
RSP: 0018:ffffc90004a4fb88 EFLAGS: 00000082
RAX: 1ffffffff19c25fd RBX: ffff888078ee3508 RCX: ffffffff81677953
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff888078ee3508
RBP: ffff888078ee3510 R08: 0000000000000000 R09: ffffed100f1dc6a1
R10: ffff888078ee350b R11: 0000000000000002 R12: ffff888078ee3518
R13: 0000000000000000 R14: 0000000000000283 R15: ffff888078ee3508
FS:  00007f01414ba6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c013f5d000 CR3: 00000000285a7000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
 do_raw_spin_unlock+0x173/0x230 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock_irqrestore+0x22/0x70 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 eventfd_signal_mask+0x176/0x1d0 fs/eventfd.c:69
 vhost_update_used_flags+0x351/0x3e0 drivers/vhost/vhost.c:2274
 vhost_enable_notify+0xd2/0xa30 drivers/vhost/vhost.c:2818
 vhost_vsock_handle_tx_kick+0x8a5/0xbe0 drivers/vhost/vsock.c:512
 vhost_worker+0x17e/0x200 drivers/vhost/vhost.c:411
 vhost_task_fn+0x16a/0x370 kernel/vhost_task.c:55
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>