INFO: task syz-executor206:7707 blocked for more than 140 seconds. Not tainted 4.19.51 #23 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor206 D27936 7707 7706 0x80000002 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x116/0x6d0 kernel/kthread.c:550 vivid_stop_generating_vid_cap+0x1e0/0x6e2 drivers/media/platform/vivid/vivid-kthread-cap.c:922 vid_cap_stop_streaming+0x8a/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:256 __vb2_queue_cancel+0xb1/0x960 drivers/media/common/videobuf2/videobuf2-core.c:1678 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1812 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2339 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2066 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:671 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:842 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:856 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:474 v4l2_release+0xf9/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x933/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 __do_sys_exit_group kernel/exit.c:990 [inline] __se_sys_exit_group kernel/exit.c:988 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443ba8 Code: 20 66 69 6c 65 20 63 61 63 68 65 2c 20 66 69 6c 65 20 27 25 73 27 2e 0a 00 00 77 72 69 74 65 20 74 6f 20 73 74 72 65 61 6d 2c <20> 70 44 61 74 61 2d 3e 70 53 74 72 6d 20 25 70 2c 20 6c 65 6e 42 RSP: 002b:00007ffc49b40ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443ba8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c3510 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor206:7709 blocked for more than 140 seconds. Not tainted 4.19.51 #23 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor206 D27040 7709 7702 0x80000002 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x116/0x6d0 kernel/kthread.c:550 vivid_stop_generating_vid_cap+0x1e0/0x6e2 drivers/media/platform/vivid/vivid-kthread-cap.c:922 vid_cap_stop_streaming+0x8a/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:256 __vb2_queue_cancel+0xb1/0x960 drivers/media/common/videobuf2/videobuf2-core.c:1678 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1812 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2339 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2066 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:671 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:842 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:856 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:474 v4l2_release+0xf9/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x933/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 __do_sys_exit_group kernel/exit.c:990 [inline] __se_sys_exit_group kernel/exit.c:988 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443ba8 Code: 20 66 69 6c 65 20 63 61 63 68 65 2c 20 66 69 6c 65 20 27 25 73 27 2e 0a 00 00 77 72 69 74 65 20 74 6f 20 73 74 72 65 61 6d 2c <20> 70 44 61 74 61 2d 3e 70 53 74 72 6d 20 25 70 2c 20 6c 65 6e 42 RSP: 002b:00007ffc49b40ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443ba8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c3510 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor206:7732 blocked for more than 140 seconds. Not tainted 4.19.51 #23 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor206 D28216 7732 7705 0x80000002 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x116/0x6d0 kernel/kthread.c:550 vivid_stop_generating_vid_cap+0x1e0/0x6e2 drivers/media/platform/vivid/vivid-kthread-cap.c:922 vid_cap_stop_streaming+0x8a/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:256 __vb2_queue_cancel+0xb1/0x960 drivers/media/common/videobuf2/videobuf2-core.c:1678 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1812 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2339 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2066 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:671 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:842 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:856 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:474 v4l2_release+0xf9/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x933/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 __do_sys_exit_group kernel/exit.c:990 [inline] __se_sys_exit_group kernel/exit.c:988 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443ba8 Code: 20 66 69 6c 65 20 63 61 63 68 65 2c 20 66 69 6c 65 20 27 25 73 27 2e 0a 00 00 77 72 69 74 65 20 74 6f 20 73 74 72 65 61 6d 2c <20> 70 44 61 74 61 2d 3e 70 53 74 72 6d 20 25 70 2c 20 6c 65 6e 42 RSP: 002b:00007ffc49b40ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443ba8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c3510 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor206:7844 blocked for more than 140 seconds. Not tainted 4.19.51 #23 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor206 D28216 7844 7701 0x80000002 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x116/0x6d0 kernel/kthread.c:550 vivid_stop_generating_vid_cap+0x1e0/0x6e2 drivers/media/platform/vivid/vivid-kthread-cap.c:922 vid_cap_stop_streaming+0x8a/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:256 __vb2_queue_cancel+0xb1/0x960 drivers/media/common/videobuf2/videobuf2-core.c:1678 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1812 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2339 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2066 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:671 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:842 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:856 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:474 v4l2_release+0xf9/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x933/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 __do_sys_exit_group kernel/exit.c:990 [inline] __se_sys_exit_group kernel/exit.c:988 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443ba8 Code: 20 66 69 6c 65 20 63 61 63 68 65 2c 20 66 69 6c 65 20 27 25 73 27 2e 0a 00 00 77 72 69 74 65 20 74 6f 20 73 74 72 65 61 6d 2c <20> 70 44 61 74 61 2d 3e 70 53 74 72 6d 20 25 70 2c 20 6c 65 6e 42 RSP: 002b:00007ffc49b40ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443ba8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c3510 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor206:8002 blocked for more than 140 seconds. Not tainted 4.19.51 #23 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor206 D28216 8002 7704 0x80000002 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x116/0x6d0 kernel/kthread.c:550 vivid_stop_generating_vid_cap+0x1e0/0x6e2 drivers/media/platform/vivid/vivid-kthread-cap.c:922 vid_cap_stop_streaming+0x8a/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:256 __vb2_queue_cancel+0xb1/0x960 drivers/media/common/videobuf2/videobuf2-core.c:1678 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1812 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2339 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2066 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:671 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:842 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:856 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:474 v4l2_release+0xf9/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x933/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 __do_sys_exit_group kernel/exit.c:990 [inline] __se_sys_exit_group kernel/exit.c:988 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443ba8 Code: 20 66 69 6c 65 20 63 61 63 68 65 2c 20 66 69 6c 65 20 27 25 73 27 2e 0a 00 00 77 72 69 74 65 20 74 6f 20 73 74 72 65 61 6d 2c <20> 70 44 61 74 61 2d 3e 70 53 74 72 6d 20 25 70 2c 20 6c 65 6e 42 RSP: 002b:00007ffc49b40ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443ba8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c3510 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1033: #0: 000000003f8cd084 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/7552: 2 locks held by getty/7673: #0: 00000000089a8090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000fdc141cb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7674: #0: 00000000332a7c97 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000000de31e7f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7675: #0: 00000000761dd6b1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000002d64a906 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7676: #0: 00000000a0d01acc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000de34e11a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7677: #0: 000000007ac57790 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000e52805c2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7678: #0: 00000000c80d752c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000642a9bbe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7679: #0: 00000000926d6126 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000eb307af7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1033 Comm: khungtaskd Not tainted 4.19.51 #23 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60