INFO: task syz.0.17:6420 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:27072 pid:6420 tgid:6420 ppid:6315 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 __vhost_worker_flush+0x17f/0x230 drivers/vhost/vhost.c:296 vhost_worker_flush drivers/vhost/vhost.c:303 [inline] vhost_dev_flush+0xb8/0x140 drivers/vhost/vhost.c:313 vhost_vsock_flush drivers/vhost/vsock.c:718 [inline] vhost_vsock_dev_release+0x23a/0x6d0 drivers/vhost/vsock.c:776 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb5bbd9aeb9 RSP: 002b:00007fffeeb61e18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fb5bc017da0 RCX: 00007fb5bbd9aeb9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fb5bc017da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007fb5bc017cb0 R11: 0000000000000246 R12: 0000000000022eb6 R13: 00007fb5bc015fac R14: 0000000000022bce R15: 00007fffeeb61f20 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by klogd/5174: #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by getty/5577: #0: ffff888036cb20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: 8e 6d 02 e9 8e 22 63 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 3d 1c 00 fb f4 67 22 63 f5 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000246 RAX: 000000000017f209 RBX: ffffffff819a80ad RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8def1e84 RDI: ffffffff8c27a880 RBP: ffffffff8e407eb0 R08: ffff8880b863395b R09: 1ffff110170c672b R10: dffffc0000000000 R11: ffffed10170c672c R12: ffffffff90117db0 R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125466000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055dda43560e0 CR3: 000000000e54c000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1bd/0x500 kernel/sched/idle.c:332 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430 rest_init+0x2de/0x300 init/main.c:760 start_kernel+0x385/0x3d0 init/main.c:1210 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147