INFO: task syz-executor037:6861 blocked for more than 140 seconds. Not tainted 4.14.150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor037 D28528 6861 6854 0x80000002 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 kthread_stop+0xda/0x650 kernel/kthread.c:530 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x7df/0x2c10 kernel/exit.c:874 do_group_exit+0x111/0x330 kernel/exit.c:977 SYSC_exit_group kernel/exit.c:988 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:986 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443b88 RSP: 002b:00007fff89bd15b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443b88 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c34f0 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor037:6997 blocked for more than 140 seconds. Not tainted 4.14.150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor037 D28528 6997 6855 0x80000002 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 kthread_stop+0xda/0x650 kernel/kthread.c:530 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x7df/0x2c10 kernel/exit.c:874 do_group_exit+0x111/0x330 kernel/exit.c:977 SYSC_exit_group kernel/exit.c:988 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:986 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443b88 RSP: 002b:00007fff89bd15b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443b88 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c34f0 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor037:7007 blocked for more than 140 seconds. Not tainted 4.14.150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor037 D28528 7007 6858 0x80000002 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 kthread_stop+0xda/0x650 kernel/kthread.c:530 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x7df/0x2c10 kernel/exit.c:874 do_group_exit+0x111/0x330 kernel/exit.c:977 SYSC_exit_group kernel/exit.c:988 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:986 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443b88 RSP: 002b:00007fff89bd15b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443b88 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c34f0 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor037:7009 blocked for more than 140 seconds. Not tainted 4.14.150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor037 D28528 7009 6857 0x80000002 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 kthread_stop+0xda/0x650 kernel/kthread.c:530 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x7df/0x2c10 kernel/exit.c:874 do_group_exit+0x111/0x330 kernel/exit.c:977 SYSC_exit_group kernel/exit.c:988 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:986 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443b88 RSP: 002b:00007fff89bd15b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443b88 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c34f0 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor037:7014 blocked for more than 140 seconds. Not tainted 4.14.150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor037 D28528 7014 6856 0x80000002 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 kthread_stop+0xda/0x650 kernel/kthread.c:530 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x7df/0x2c10 kernel/exit.c:874 do_group_exit+0x111/0x330 kernel/exit.c:977 SYSC_exit_group kernel/exit.c:988 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:986 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x443b88 RSP: 002b:00007fff89bd15b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443b88 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c34f0 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1016: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/6703: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/6826: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6827: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6828: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6829: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6830: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6831: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/6832: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1016 Comm: khungtaskd Not tainted 4.14.150 #0 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+0x138/0x197 lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6853 Comm: syz-executor037 Not tainted 4.14.150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888089172300 task.stack: ffff8880a8758000 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:60 RSP: 0018:ffff8880a875fb40 EFLAGS: 00000202 RAX: 0000000080000002 RBX: ffffffff87ab2dc0 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff869d3220 RDI: ffffffff869d3260 RBP: ffff8880a875fb78 R08: 0000000000007edc R09: ffffffff88cc0ba0 R10: ffff888089172b80 R11: ffff888089172300 R12: 0000000000000000 R13: ffffffff869d3220 R14: ffffffff869d3260 R15: 0000000001200011 FS: 0000000001e60880(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff89bd1604 CR3: 000000008adc4000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_smp_processor_id+0x1c/0x20 lib/smp_processor_id.c:57 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:360 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:1130 rcu_read_lock_sched_held+0x8e/0x130 kernel/rcu/update.c:111 rcu_sync_lockdep_assert+0x6d/0xb0 kernel/rcu/sync.c:68 rcu_sync_is_idle include/linux/rcu_sync.h:56 [inline] percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:48 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline] copy_process.part.0+0x2c13/0x6a00 kernel/fork.c:1852 copy_process kernel/fork.c:1595 [inline] _do_fork+0x19e/0xce0 kernel/fork.c:2085 SYSC_clone kernel/fork.c:2195 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2189 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4438da RSP: 002b:00007fff89bd15d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004438da RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007fff89bd15f0 R08: 0000000000001ac5 R09: 0000000001e60880 R10: 0000000001e60b50 R11: 0000000000000246 R12: 0000000000001ac5 R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000 Code: 00 00 48 c7 c7 20 9b 6e 86 4c 89 35 9b 5e be 07 41 be f4 ff ff ff e8 a3 3b ee ff 48 c7 05 85 5e be 07 00 00 00 00 e9 2f ec ff ff <65> 48 8b 04 25 40 ee 01 00 48 85 c0 74 1a 65 8b 15 bb f9 a4 7e