INFO: task kworker/0:4:3224 blocked for more than 143 seconds. Not tainted 5.6.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D23848 3224 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0xc/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x87c/0x1360 kernel/locking/mutex.c:1103 input_disconnect_device drivers/input/input.c:732 [inline] __input_unregister_device+0x23/0x430 drivers/input/input.c:2085 input_unregister_device+0xb4/0xf0 drivers/input/input.c:2272 iforce_usb_disconnect+0x5e/0xf0 drivers/input/joystick/iforce/iforce-usb.c:261 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436 __device_release_driver drivers/base/dd.c:1137 [inline] device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1168 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2677 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211 hub_port_connect drivers/usb/core/hub.c:5046 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 worker_thread+0x96/0xe20 kernel/workqueue.c:2410 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: ffffffff87109060 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5331 6 locks held by kworker/0:2/95: #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d5907dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d493c200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d493c200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d493e540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:3008 [inline] #3: ffff8881d493e540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5126 [inline] #3: ffff8881d493e540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] #3: ffff8881d493e540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5481 [inline] #3: ffff8881d493e540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1fae/0x4300 drivers/usb/core/hub.c:5563 #4: ffff8881d4fc4460 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2e60 drivers/usb/core/hub.c:4550 #5: ffffffff8767fb08 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x186/0x1790 drivers/usb/core/hub.c:2870 2 locks held by systemd-journal/150: #0: ffff8881db334658 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8881db334658 (&rq->lock){-.-.}, at: __schedule+0x21c/0x1d80 kernel/sched/core.c:4028 #1: ffffffff87109060 (rcu_read_lock){....}, at: __update_idle_core+0x42/0x3f0 kernel/sched/fair.c:5747 1 lock held by in:imklog/277: #0: ffff8881d8d29260 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:821 2 locks held by agetty/266: #0: ffff8881d2790090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004d32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 6 locks held by kworker/1:3/3049: #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d1e1fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d48be200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d48be200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d0212200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881d0212200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881d8ddd190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 #5: ffff8881d430e2a8 (&dev->mutex#2){+.+.}, at: input_disconnect_device drivers/input/input.c:732 [inline] #5: ffff8881d430e2a8 (&dev->mutex#2){+.+.}, at: __input_unregister_device+0x23/0x430 drivers/input/input.c:2085 6 locks held by kworker/0:4/3224: #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d2c928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881cb3dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4915200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4915200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881ca970200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ca970200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881cfdc2190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 #5: ffff8881ce5472a8 (&dev->mutex#2){+.+.}, at: input_disconnect_device drivers/input/input.c:732 [inline] #5: ffff8881ce5472a8 (&dev->mutex#2){+.+.}, at: __input_unregister_device+0x23/0x430 drivers/input/input.c:2085 2 locks held by systemd-udevd/10097: #0: ffff8881cd267148 (&evdev->mutex){+.+.}, at: evdev_close_device drivers/input/evdev.c:425 [inline] #0: ffff8881cd267148 (&evdev->mutex){+.+.}, at: evdev_release+0xeb/0x1c0 drivers/input/evdev.c:466 #1: ffff8881ce5472a8 (&dev->mutex#2){+.+.}, at: input_close_device+0x42/0x1a0 drivers/input/input.c:673 2 locks held by systemd-udevd/11127: #0: ffff8881d8f20148 (&evdev->mutex){+.+.}, at: evdev_close_device drivers/input/evdev.c:425 [inline] #0: ffff8881d8f20148 (&evdev->mutex){+.+.}, at: evdev_release+0xeb/0x1c0 drivers/input/evdev.c:466 #1: ffff8881d430e2a8 (&dev->mutex#2){+.+.}, at: input_close_device+0x42/0x1a0 drivers/input/input.c:673 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.6.0-rc5-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+0xef/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1db/0x207 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+0xa99/0xfd0 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0x28/0x300 arch/x86/kernel/process.c:695