INFO: task kworker/0:1:10324 blocked for more than 143 seconds. Not tainted 5.1.0-rc4-319354-g9a33b36 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:1 D21344 10324 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x11/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x800/0x12b0 kernel/locking/mutex.c:1072 i2c_del_adapter+0x29/0x640 drivers/i2c/i2c-core-base.c:1453 vprbrd_i2c_remove+0x38/0x50 drivers/i2c/busses/i2c-viperboard.c:419 platform_drv_remove+0x6d/0xa0 drivers/base/platform.c:640 __device_release_driver drivers/base/dd.c:1082 [inline] device_release_driver_internal+0x436/0x4f0 drivers/base/dd.c:1113 bus_remove_device+0x302/0x5c0 drivers/base/bus.c:556 device_del+0x467/0xb90 drivers/base/core.c:2269 platform_device_del.part.0+0x24/0x220 drivers/base/platform.c:485 platform_device_del include/linux/err.h:41 [inline] platform_device_unregister+0x3d/0x80 drivers/base/platform.c:523 mfd_remove_devices_fn drivers/mfd/mfd-core.c:324 [inline] mfd_remove_devices_fn+0x147/0x1c0 drivers/mfd/mfd-core.c:305 device_for_each_child_reverse+0x117/0x180 drivers/base/core.c:2431 mfd_remove_devices+0x7b/0xb0 drivers/mfd/mfd-core.c:332 vprbrd_disconnect+0x48/0x100 drivers/mfd/viperboard.c:116 usb_unbind_interface+0x1c9/0x980 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1082 [inline] device_release_driver_internal+0x436/0x4f0 drivers/base/dd.c:1113 bus_remove_device+0x302/0x5c0 drivers/base/bus.c:556 device_del+0x467/0xb90 drivers/base/core.c:2269 usb_disable_device+0x242/0x790 drivers/usb/core/message.c:1235 usb_disconnect+0x298/0x870 drivers/usb/core/hub.c:2197 hub_port_connect drivers/usb/core/hub.c:4940 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0xcd2/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 process_scheduled_works kernel/workqueue.c:2331 [inline] worker_thread+0x7b0/0xe20 kernel/workqueue.c:2417 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 9 locks held by kworker/0:0/5: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000900cf050 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 000000003a3c3d47 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 000000003a3c3d47 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 0000000032d37e6b (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 0000000032d37e6b (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #4: 00000000ba592e74 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #4: 00000000ba592e74 (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #5: 00000000551045f5 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #5: 00000000551045f5 (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #6: 0000000078101c7e (core_lock){+.+.}, at: i2c_register_adapter+0x507/0xb30 drivers/i2c/i2c-core-base.c:1292 #7: 00000000d1dd4dae (i2c_register_adapter){+.+.}, at: i2c_lock_bus include/linux/i2c.h:739 [inline] #7: 00000000d1dd4dae (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x79/0x130 drivers/i2c/i2c-core-smbus.c:533 #8: 00000000ee4850c6 (&vb->lock){+.+.}, at: vprbrd_i2c_xfer+0x1a3/0x1b9e drivers/i2c/busses/i2c-viperboard.c:291 5 locks held by kworker/1:0/17: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000c54f42a0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 0000000023409f12 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 0000000023409f12 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 000000001fac4800 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2994 [inline] #3: 000000001fac4800 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5020 [inline] #3: 000000001fac4800 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] #3: 000000001fac4800 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5350 [inline] #3: 000000001fac4800 (&port_dev->status_lock){+.+.}, at: hub_event+0x11a3/0x3b00 drivers/usb/core/hub.c:5432 #4: 00000000509a054a (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1bb/0x2d30 drivers/usb/core/hub.c:4529 1 lock held by khungtaskd/23: #0: 00000000ef5e506c (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5059 6 locks held by kworker/1:2/533: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000e1b93663 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000aca6c7cf (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000aca6c7cf (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 0000000021f2f951 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 0000000021f2f951 (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #4: 000000004b678e9c (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #4: 000000004b678e9c (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #5: 00000000169b491a (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #5: 00000000169b491a (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 5 locks held by kworker/0:3/558: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000236e0784 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000ef9c934e (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000ef9c934e (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 00000000e55bf5ac (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 00000000e55bf5ac (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #4: 0000000033fa0d7f (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #4: 0000000033fa0d7f (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 1 lock held by rsyslogd/5332: #0: 000000002b85c81b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe8/0x100 fs/file.c:801 2 locks held by getty/5422: #0: 0000000068991742 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000004fb045f6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5423: #0: 0000000087840075 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000d05ea3d5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5424: #0: 00000000d5ef7ed9 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000053fb3df1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5425: #0: 00000000ea757f02 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000ad9ab2c5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5426: #0: 00000000ccbb6013 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000bf6b3ebf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5427: #0: 000000003b2c7d37 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000abf6c619 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5428: #0: 00000000f20d6e30 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000004f12719e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 5 locks held by kworker/1:5/5677: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000705d0f2c ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000de2b6e4c (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000de2b6e4c (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 00000000b0c94199 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2994 [inline] #3: 00000000b0c94199 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5020 [inline] #3: 00000000b0c94199 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] #3: 00000000b0c94199 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5350 [inline] #3: 00000000b0c94199 (&port_dev->status_lock){+.+.}, at: hub_event+0x11a3/0x3b00 drivers/usb/core/hub.c:5432 #4: 000000007fb9ca5a (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1bb/0x2d30 drivers/usb/core/hub.c:4529 7 locks held by kworker/0:1/10324: #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000c5fcdff4 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 000000004ce3bf65 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000c8618c08 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000c8618c08 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 00000000b28196a8 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 00000000b28196a8 (&dev->mutex){....}, at: usb_disconnect+0x96/0x870 drivers/usb/core/hub.c:2188 #4: 000000004b4063f0 (&dev->mutex){....}, at: device_release_driver_internal+0x28/0x4f0 drivers/base/dd.c:1110 #5: 00000000b7e6ce98 (&dev->mutex){....}, at: device_release_driver_internal+0x28/0x4f0 drivers/base/dd.c:1110 #6: 0000000078101c7e (core_lock){+.+.}, at: i2c_del_adapter+0x29/0x640 drivers/i2c/i2c-core-base.c:1453 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.1.0-rc4-319354-g9a33b36 #3 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+0xe8/0x16e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x48/0x87 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1bd lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x98e/0xe20 kernel/hung_task.c:288 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 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+0x2/0x10 arch/x86/include/asm/irqflags.h:57