Buffer I/O error on dev loop0, logical block 6, lost async page write Buffer I/O error on dev loop0, logical block 7, lost async page write Buffer I/O error on dev loop0, logical block 8, lost async page write Buffer I/O error on dev loop0, logical block 9, lost async page write Buffer I/O error on dev loop0, logical block 10, lost async page write INFO: rcu_sched self-detected stall on CPU 1-....: (124998 ticks this GP) idle=9b2/1/4611686018427387906 softirq=22733/22733 fqs=31170 (t=125000 jiffies g=11599 c=11598 q=1619) NMI backtrace for cpu 1 CPU: 1 PID: 7184 Comm: syz-executor3 Not tainted 4.16.0+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b9/0x29f lib/dump_stack.c:53 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline] rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1376 print_cpu_stall kernel/rcu/tree.c:1525 [inline] check_cpu_stall.isra.61.cold.80+0x36c/0x59a kernel/rcu/tree.c:1593 __rcu_pending kernel/rcu/tree.c:3356 [inline] rcu_pending kernel/rcu/tree.c:3401 [inline] rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763 update_process_times+0x2d/0x70 kernel/time/timer.c:1636 tick_sched_handle+0xa0/0x180 kernel/time/tick-sched.c:171 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1179 __run_hrtimer kernel/time/hrtimer.c:1337 [inline] __hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1399 hrtimer_interrupt+0x286/0x650 kernel/time/hrtimer.c:1457 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:862 RIP: 0010:__sanitizer_cov_trace_pc+0x2b/0x50 kernel/kcov.c:101 RSP: 0018:ffff8801cfe77710 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffff8801d0108080 RBX: 0000000000000004 RCX: ffffffff85a1f955 RDX: 0000000000000002 RSI: ffffffff85a1f95f RDI: 0000000000000005 RBP: ffff8801cfe77710 R08: ffff8801d0108080 R09: 0000000000000006 R10: ffff8801d0108080 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8801ceb2cd80 R14: ffff8801aaacec00 R15: ffffffffffffffe0 snd_pcm_oss_write3+0x16f/0x220 sound/core/oss/pcm_oss.c:1224 io_playback_transfer+0x274/0x310 sound/core/oss/io.c:47 snd_pcm_plug_write_transfer+0x36c/0x470 sound/core/oss/pcm_plugin.c:619 snd_pcm_oss_write2+0x25c/0x460 sound/core/oss/pcm_oss.c:1365 snd_pcm_oss_sync1+0x332/0x5a0 sound/core/oss/pcm_oss.c:1606 snd_pcm_oss_sync.isra.29+0x790/0x980 sound/core/oss/pcm_oss.c:1682 snd_pcm_oss_release+0x214/0x290 sound/core/oss/pcm_oss.c:2559 __fput+0x34d/0x890 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1e4/0x290 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x792/0x9d0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4552d9 RSP: 002b:00007f4e5ffe6c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f4e5ffe76d4 RCX: 00000000004552d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000052 R14: 00000000006f3850 R15: 0000000000000000 INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 1-... } 127452 jiffies s: 2685 root: 0x2/. blocking rcu_node structures: Task dump for CPU 1: syz-executor3 R running task 24120 7184 4559 0x0000000c Call Trace: