INFO: task syz.3.3995:22491 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.3995 state:D stack:24280 pid:22491 tgid:22491 ppid:20564 task_flags:0x400040 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148
vhost_task_stop+0xbf/0xd0 kernel/vhost_task.c:102
kvm_destroy_vm virt/kvm/kvm_main.c:1277 [inline]
kvm_put_kvm+0x327/0x1650 virt/kvm/kvm_main.c:1346
kvm_vm_release+0x43/0x50 virt/kvm/kvm_main.c:1369
__fput+0x449/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f674a78e969
RSP: 002b:00007f674aadfb88 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f674a9b7ba0 RCX: 00007f674a78e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f674a9b7ba0 R08: 000000000000bc64 R09: 0000000b4aadfe7f
R10: 00007f674a9b7ac0 R11: 0000000000000246 R12: 000000000013e732
R13: 00007f674aadfc80 R14: ffffffffffffffff R15: 00007f674aadfca0
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5593:
#0: ffff888034b920a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by kworker/u8:20/8638:
1 lock held by syz.6.4411/24394:
#0: ffffffff8df43880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
1 lock held by syz.5.4412/24401:
1 lock held by syz.7.4419/24430:
#0: ffff88805c8dd4d8 (&runtime->oss.params_lock){+.+.}-{4:4}, at: snd_pcm_oss_sync+0x297/0xc30 sound/core/oss/pcm_oss.c:1663
1 lock held by syz.7.4419/24431:
#0: ffff88805c8dd4d8 (&runtime->oss.params_lock){+.+.}-{4:4}, at: lock_params sound/core/oss/pcm_oss.c:820 [inline]
#0: ffff88805c8dd4d8 (&runtime->oss.params_lock){+.+.}-{4:4}, at: snd_pcm_oss_set_rate+0x134/0x4e0 sound/core/oss/pcm_oss.c:1760
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.15.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81
Code: c3 d4 02 00 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 63 7f 11 00 f3 0f 1e fa fb f4 <e9> 98 d4 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 6e0c903d22c44700 RBX: ffffffff81977108 RCX: 6e0c903d22c44700
RDX: 0000000000000001 RSI: ffffffff8d74e306 RDI: ffffffff8bc1f540
RBP: ffffffff8dc07ec0 R08: ffff8880b8832b5b R09: 1ffff1101710656b
R10: dffffc0000000000 R11: ffffed101710656c R12: ffffffff8f7f3570
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b92a48
FS: 0000000000000000(0000) GS:ffff8881260c2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcb6ef7d2d8 CR3: 000000002d79e000 CR4: 00000000003526f0
DR0: 0000000000000007 DR1: 000000000000000b DR2: 0000000000000002
DR3: 0000000000000009 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:748
default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
rest_init+0x2de/0x300 init/main.c:743
start_kernel+0x470/0x4f0 init/main.c:1099
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:513
x86_64_start_kernel+0x66/0x70 arch/x86/kernel/head64.c:494
common_startup_64+0x13e/0x147
</TASK>
vkms_vblank_simulate: vblank timer overrun