INFO: task syz-executor.0:16673 blocked for more than 140 seconds. Not tainted 4.19.76 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28216 16673 8207 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 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+0x116/0x6c0 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: 0033:0x413711 Code: 48 8b 54 24 30 48 39 ca 0f 83 80 00 00 00 c6 04 02 a1 48 85 c9 76 70 48 89 44 24 38 48 89 44 24 10 48 8b 4c 24 50 48 89 0c 24 <48> c7 44 24 08 00 00 00 00 48 c7 44 24 18 01 00 00 00 e8 68 00 00 RSP: 002b:00007fff1a2992d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000413711 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000001 R08: 00000000dd520863 R09: 00000000dd520867 R10: 00007fff1a2993b0 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000761978 R15: 000000000075bfd4 Showing all locks held in the system: 1 lock held by khungtaskd/1039: #0: 00000000c4defd64 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/7351: 2 locks held by getty/7474: #0: 000000000035e215 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000ce5705a7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7475: #0: 0000000057211e46 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000002286e027 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7476: #0: 00000000f39925cd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000037a517bc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7477: #0: 000000001fb695b8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000631179bf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7478: #0: 0000000021518ae2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000001b4facf1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7479: #0: 000000009800ace9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000008f7209b9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7480: #0: 0000000007226b7a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a1b174c7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1039 Comm: khungtaskd Not tainted 4.19.76 #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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7349 Comm: rs:main Q:Reg Not tainted 4.19.76 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ext4_ext_insert_extent+0x2381/0x43d0 fs/ext4/extents.c:2012 Code: ff 41 89 c6 89 c6 e8 ce 85 87 ff 45 85 f6 0f 84 16 e1 ff ff e9 55 ee ff ff e8 3b 84 87 ff 41 81 ed 00 80 00 00 e9 3f fc ff ff 2a 84 87 ff 48 8b 8d 60 ff ff ff 48 b8 00 00 00 00 00 fc ff df RSP: 0018:ffff88809e13f198 EFLAGS: 00000a87 RAX: 0000000000000000 RBX: 0000000000000012 RCX: ffffffff81e3c099 RDX: 0000000000000011 RSI: 0000000000008000 RDI: 0000000000000003 RBP: ffff88809e13f2e0 R08: ffff888085306240 R09: ffffed1015d04733 R10: ffffed1015d04732 R11: ffff8880ae823993 R12: ffff88808e832664 R13: 0000000000000001 R14: 0000000000000011 R15: ffff88808e832830 FS: 00007f81caf58700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001894000 CR3: 0000000091731000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_ext_map_blocks+0x1a5b/0x55c0 fs/ext4/extents.c:4510 ext4_map_blocks+0x990/0x1b20 fs/ext4/inode.c:640 mpage_map_one_extent fs/ext4/inode.c:2460 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2513 [inline] ext4_writepages+0x1e5b/0x3450 fs/ext4/inode.c:2865 do_writepages+0xf3/0x2a0 mm/page-writeback.c:2347 __filemap_fdatawrite_range+0x26d/0x340 mm/filemap.c:445 file_write_and_wait_range+0x9a/0x100 mm/filemap.c:775 __generic_file_fsync+0x79/0x200 fs/libfs.c:977 ext4_sync_file+0x826/0x1450 fs/ext4/fsync.c:120 vfs_fsync_range+0x141/0x230 fs/sync.c:197 generic_write_sync include/linux/fs.h:2746 [inline] ext4_file_write_iter+0x7a0/0x1060 fs/ext4/file.c:281 call_write_iter include/linux/fs.h:1820 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x587/0x810 fs/read_write.c:487 vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:608 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f81cc9b619d Code: d1 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 be fa ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 07 fb ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f81caf56f90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007f81cc9b619d RDX: 0000000000000400 RSI: 000000000187c340 RDI: 0000000000000002 RBP: 000000000187c340 R08: 656c6c616b7a7973 R09: 6c656e72656b2072 R10: 33343420205b203a R11: 0000000000000293 R12: 0000000000000000 R13: 00007f81caf57410 R14: 00000000019207f0 R15: 000000000187c140