INFO: task kworker/1:4:3319 blocked for more than 143 seconds. Not tainted 5.4.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:4 D23752 3319 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xca/0x250 kernel/sched/core.c:4136 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1871 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+0x26f/0x3c0 kernel/sched/completion.c:136 kthread_stop+0x10c/0x610 kernel/kthread.c:559 dvb_ca_en50221_release+0x91/0x200 drivers/media/dvb-core/dvb_ca_en50221.c:1934 tt3650_ci_uninit drivers/media/usb/dvb-usb/pctv452e.c:364 [inline] pctv452e_usb_disconnect+0xb0/0xf0 drivers/media/usb/dvb-usb/pctv452e.c:1061 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1134 [inline] device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532 device_del+0x420/0xb20 drivers/base/core.c:2376 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2200 hub_port_connect drivers/usb/core/hub.c:5035 [inline] hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] port_event drivers/usb/core/hub.c:5470 [inline] hub_event+0x16f2/0x3800 drivers/usb/core/hub.c:5552 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 worker_thread+0x96/0xe20 kernel/workqueue.c:2415 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: ffffffff86cfe8a0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5335 6 locks held by kworker/1:2/83: #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881d89f7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d51ed200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d51ed200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881d51ef520 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2997 [inline] #3: ffff8881d51ef520 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5115 [inline] #3: ffff8881d51ef520 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] #3: ffff8881d51ef520 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5470 [inline] #3: ffff8881d51ef520 (&port_dev->status_lock){+.+.}, at: hub_event+0x1c06/0x3800 drivers/usb/core/hub.c:5552 #4: ffff8881d5192160 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2d30 drivers/usb/core/hub.c:4539 #5: ffffffff871e6fa8 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x17b/0x1460 drivers/usb/core/hub.c:2859 1 lock held by rsyslogd/1598: #0: ffff8881d372f9e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1688: #0: ffff8881d1bf0090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004652e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1689: #0: ffff8881d21fa090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000044d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1690: #0: ffff8881d238f090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004452e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1691: #0: ffff8881d149d090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1692: #0: ffff8881d3b78090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000046d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1693: #0: ffff8881d1547090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004612e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1694: #0: ffff8881d21e3090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000043d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 5 locks held by kworker/1:4/3319: #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8ff4928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881d13b7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d51ce200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d51ce200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881c1982200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881c1982200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881d15a3190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 8 locks held by kworker/1:7/6231: #0: ffff8881db331e58 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8881db331e58 (&rq->lock){-.-.}, at: __schedule+0x21c/0x1ca0 kernel/sched/core.c:4017 #1: ffffffff86cfe8a0 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:435 [inline] #1: ffffffff86cfe8a0 (rcu_read_lock){....}, at: update_curr+0x281/0x810 kernel/sched/fair.c:860 #2: ffffffff86d32cf8 (kcov_remote_lock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: ffffffff86d32cf8 (kcov_remote_lock){+.+.}, at: kcov_remote_stop+0x8c/0x1d0 kernel/kcov.c:903 #3: ffff8881d5132330 (&dev->power.wait_queue){..-.}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:122 #4: ffff8881d5447090 (&hub->status_mutex){+.+.}, at: hub_ext_port_status+0x58/0x460 drivers/usb/core/hub.c:586 #5: ffffffff891d8f40 (&obj_hash[i].lock){-.-.}, at: __debug_check_no_obj_freed lib/debugobjects.c:951 [inline] #5: ffffffff891d8f40 (&obj_hash[i].lock){-.-.}, at: debug_check_no_obj_freed+0xc4/0x443 lib/debugobjects.c:994 #6: ffff8881da249fa8 (&p->pi_lock){-.-.}, at: try_to_wake_up+0x99/0x15d0 kernel/sched/core.c:2551 #7: ffff8881db331e58 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #7: ffff8881db331e58 (&rq->lock){-.-.}, at: ttwu_queue kernel/sched/core.c:2407 [inline] #7: ffff8881db331e58 (&rq->lock){-.-.}, at: try_to_wake_up+0xaf0/0x15d0 kernel/sched/core.c:2643 1 lock held by kdvb-ca-0:0/9867: 2 locks held by kworker/u4:2/10249: #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881af51fdd0 (connector_reaper_work){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 1 lock held by syz-executor.0/12305: #0: ffff8881d53c2148 (&evdev->mutex){+.+.}, at: evdev_flush+0x6f/0x140 drivers/input/evdev.c:334 1 lock held by syz-executor.0/12309: #0: ffff8881d53c2148 (&evdev->mutex){+.+.}, at: evdev_release+0x7f/0x1c0 drivers/input/evdev.c:455 1 lock held by syz-executor.0/12310: 3 locks held by syz-executor.3/12342: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.4.0-rc6-syzkaller #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+0xca/0x13e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9a4/0xe50 kernel/hung_task.c:289 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9867 Comm: kdvb-ca-0:0 Not tainted 5.4.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:vsnprintf+0x14d/0x14f0 lib/vsprintf.c:2462 Code: 00 49 8d 47 08 48 bb 00 00 00 00 00 fc ff df 48 89 44 24 40 48 c1 e8 03 48 01 d8 48 89 44 24 30 e8 38 9b d2 fb 48 8b 74 24 08 <48> 89 ef e8 bb 70 ff ff 44 0f b6 44 24 68 48 c7 c6 e0 1c 6e 86 48 RSP: 0018:ffff8881b0fe77f0 EFLAGS: 00000093 RAX: ffff8881cb653000 RBX: dffffc0000000000 RCX: ffffffff856b8aed RDX: 0000000000000000 RSI: ffff8881b0fe7858 RDI: 0000000000000001 RBP: ffffffff85c74f80 R08: ffff8881cb653000 R09: ffffed10361fcf48 R10: ffffed10361fcf47 R11: ffff8881b0fe7a3d R12: ffff8881b0fe7a3e R13: ffffffff85c74f80 R14: 0000000000000021 R15: ffff8881b0fe78f0 FS: 0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206a01ff CR3: 00000001c5d14000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sprintf+0xc0/0x100 lib/vsprintf.c:2712 print_caller kernel/printk/printk.c:1282 [inline] print_prefix kernel/printk/printk.c:1299 [inline] msg_print_text+0x190/0x560 kernel/printk/printk.c:1316 console_unlock+0x301/0xc40 kernel/printk/printk.c:2448 vprintk_emit+0x171/0x3e0 kernel/printk/printk.c:1996 vprintk_func+0x75/0x113 kernel/printk/printk_safe.c:386 printk+0xba/0xed kernel/printk/printk.c:2056 tt3650_ci_msg.cold+0x30/0x3e drivers/media/usb/dvb-usb/pctv452e.c:141 tt3650_ci_msg_locked+0x83/0xb0 drivers/media/usb/dvb-usb/pctv452e.c:157 tt3650_ci_poll_slot_status+0x90/0x110 drivers/media/usb/dvb-usb/pctv452e.c:333 dvb_ca_en50221_check_camstatus+0x102/0x330 drivers/media/dvb-core/dvb_ca_en50221.c:234 dvb_ca_en50221_thread_state_machine drivers/media/dvb-core/dvb_ca_en50221.c:1128 [inline] dvb_ca_en50221_thread+0x26b/0x13e0 drivers/media/dvb-core/dvb_ca_en50221.c:1317 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352