INFO: task syz-executor.5:31129 blocked for more than 140 seconds. Not tainted 4.19.80 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28216 31129 31648 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1782 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+0x116/0x6c0 kernel/kthread.c:550 sdr_cap_stop_streaming+0x213/0x330 drivers/media/platform/vivid/vivid-sdr-cap.c:301 __vb2_queue_cancel+0xb1/0x790 drivers/media/common/videobuf2/videobuf2-core.c:1682 vb2_core_streamoff+0x60/0x150 drivers/media/common/videobuf2/videobuf2-core.c:1816 __vb2_cleanup_fileio+0x78/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2343 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2070 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 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413ad1 Code: 49 39 ce 72 4c 49 89 c9 4c 89 d1 4d 89 c4 49 d3 e0 48 83 f9 40 4d 19 ed 4d 21 e8 4d 09 c3 4d 8d 04 09 48 83 fb 01 74 c6 eb 1f <4d> 89 da 49 83 e3 0f 49 81 cb f0 00 00 00 44 88 1a 49 c1 ea 04 49 RSP: 002b:00007ffdf9640db0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413ad1 RDX: 0000001b2db20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffff8131011a R09: 00000000f1b0d8da R10: 00007ffdf9640e90 R11: 0000000000000293 R12: 000000000075bf20 R13: 00000000001f4a34 R14: 0000000000760298 R15: 000000000075bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1039: #0: 0000000059e0e54b (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/7261: #0: 00000000abe7b8b6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7383: #0: 0000000028185d05 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000070fefd9c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7384: #0: 00000000c923a2d7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000d6d8ecff (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7385: #0: 00000000bd896b12 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000b8f80607 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7386: #0: 00000000a5830a87 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000fa91b1ea (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7387: #0: 000000000cc40c56 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000075b3786d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7388: #0: 00000000dab13afc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000008e1b5689 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7389: #0: 00000000800f6601 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000007d9ccd1f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1039 Comm: khungtaskd Not tainted 4.19.80 #0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 313 Comm: kworker/u4:4 Not tainted 4.19.80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__sanitizer_cov_trace_pc+0x26/0x50 kernel/kcov.c:101 Code: 90 90 90 90 55 48 89 e5 48 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 78 26 97 7e 81 e2 00 01 1f 00 75 2b 8b 90 d0 12 00 00 <83> fa 02 75 20 48 8b 88 d8 12 00 00 8b 80 d4 12 00 00 48 8b 11 48 RSP: 0018:ffff88809530fcd0 EFLAGS: 00000246 RAX: ffff88806f3122c0 RBX: ffff88809118e540 RCX: ffffffff86d697b1 RDX: 0000000000000000 RSI: ffffffff86d69a40 RDI: 0000000000000001 RBP: ffff88809530fcd0 R08: ffff88806f3122c0 R09: ffffed1015d24733 R10: ffffed1015d24732 R11: ffff8880ae923993 R12: 0000000000000001 R13: 0000000000000064 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000091329000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:677 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:423 [inline] batadv_nc_worker+0x480/0x760 net/batman-adv/network-coding.c:730 process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415