INFO: task kworker/0:0:5 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/0:0 D24864 5 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 usb_get_descriptor+0xc6/0x1c0 drivers/usb/core/message.c:647 usb_get_device_descriptor+0x86/0xf0 drivers/usb/core/message.c:917 hub_port_init+0xac1/0x2d30 drivers/usb/core/hub.c:4750 hub_port_connect drivers/usb/core/hub.c:5021 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x11b8/0x3b00 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 INFO: task kworker/0:1:12 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 D22304 12 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 usb_get_descriptor+0xc6/0x1c0 drivers/usb/core/message.c:647 usb_get_configuration+0x291/0x32b0 drivers/usb/core/config.c:836 usb_enumerate_device drivers/usb/core/hub.c:2367 [inline] usb_new_device+0x2fe/0x450 drivers/usb/core/hub.c:2503 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:0:17 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/1:0 D24272 17 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 vprbrd_i2c_probe+0x2c1/0x430 drivers/i2c/busses/i2c-viperboard.c:390 platform_drv_probe+0x95/0x150 drivers/base/platform.c:614 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 platform_device_add+0x35e/0x800 drivers/base/platform.c:451 mfd_add_device+0xc29/0x1130 drivers/mfd/mfd-core.c:249 mfd_add_devices+0x11e/0x1a0 drivers/mfd/mfd-core.c:288 mfd_add_hotplug_devices include/linux/mfd/core.h:128 [inline] vprbrd_probe.cold+0x107/0x184 drivers/mfd/viperboard.c:94 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:2:533 blocked for more than 144 seconds. Not tainted 5.1.0-rc4-319354-g9a33b36 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D22592 533 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 reg_w+0xdf/0x150 drivers/media/usb/gspca/topro.c:994 sd_init+0xf2/0x70b drivers/media/usb/gspca/benq.c:97 gspca_dev_probe2+0xa75/0x146b drivers/media/usb/gspca/gspca.c:1546 gspca_dev_probe.cold+0x1a/0xbb drivers/media/usb/gspca/gspca.c:1619 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:3:563 blocked for more than 144 seconds. Not tainted 5.1.0-rc4-319354-g9a33b36 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D24832 563 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 usb_get_string+0xb1/0x1a0 drivers/usb/core/message.c:693 usb_string_sub+0x90/0x3d0 drivers/usb/core/message.c:737 usb_get_langid drivers/usb/core/message.c:769 [inline] usb_string+0x1ca/0x510 drivers/usb/core/message.c:830 usb_cache_string+0x83/0x110 drivers/usb/core/message.c:876 usb_enumerate_device drivers/usb/core/hub.c:2377 [inline] usb_new_device+0x114/0x450 drivers/usb/core/hub.c:2503 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:4:5704 blocked for more than 144 seconds. usb-fuzzer-gadget dummy_udc.5: failed to start USB fuzzer: -22 Not tainted 5.1.0-rc4-319354-g9a33b36 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D23776 5704 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x8f/0x180 kernel/sched/core.c:3562 usb_kill_urb drivers/usb/core/urb.c:695 [inline] usb_kill_urb+0x22a/0x2c0 drivers/usb/core/urb.c:687 usb_start_wait_urb+0x257/0x4d0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x321/0x4a0 drivers/usb/core/message.c:152 usb_get_string+0xb1/0x1a0 drivers/usb/core/message.c:693 usb_string_sub+0xff/0x3d0 drivers/usb/core/message.c:732 usb_get_langid drivers/usb/core/message.c:769 [inline] usb_string+0x1ca/0x510 drivers/usb/core/message.c:830 usb_cache_string+0x83/0x110 drivers/usb/core/message.c:876 usb_enumerate_device drivers/usb/core/hub.c:2380 [inline] usb_new_device+0x1e7/0x450 drivers/usb/core/hub.c:2503 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415 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: 5 locks held by kworker/0:0/5: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 000000008eedccd3 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 0000000002887ed0 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 0000000002887ed0 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 000000001cf28ef0 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2994 [inline] #3: 000000001cf28ef0 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5020 [inline] #3: 000000001cf28ef0 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] #3: 000000001cf28ef0 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5350 [inline] #3: 000000001cf28ef0 (&port_dev->status_lock){+.+.}, at: hub_event+0x11a3/0x3b00 drivers/usb/core/hub.c:5432 #4: 000000005e7fa262 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1bb/0x2d30 drivers/usb/core/hub.c:4529 3 locks held by kworker/0:1/12: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 000000008528c0dd ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 0000000051f5070a (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 0000000051f5070a (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 6 locks held by kworker/1:0/17: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000b51b0686 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000ac9eb982 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000ac9eb982 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 000000008b1325fd (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 000000008b1325fd (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #4: 00000000f4a70e50 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #4: 00000000f4a70e50 (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #5: 00000000e6a1984c (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #5: 00000000e6a1984c (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 1 lock held by khungtaskd/23: #0: 00000000ba3384c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5059 5 locks held by kworker/1:2/533: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 00000000fd7cd57a ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 000000006bd61c9d (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 000000006bd61c9d (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 #3: 000000006532763e (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #3: 000000006532763e (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 #4: 000000004623ccb2 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #4: 000000004623ccb2 (&dev->mutex){....}, at: __device_attach+0x80/0x3a0 drivers/base/dd.c:821 3 locks held by kworker/1:3/563: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 000000001beeeaaa ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 0000000069247d61 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 0000000069247d61 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 1 lock held by rsyslogd/5383: #0: 0000000043252155 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe8/0x100 fs/file.c:801 2 locks held by getty/5473: #0: 0000000021aed078 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000199ab864 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5474: #0: 00000000029be51a (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000005d07a331 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5475: #0: 00000000fa146a06 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000003246e5c1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5476: #0: 000000000467f90a (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000061ba275a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5477: #0: 000000007638008a (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000078874367 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5478: #0: 000000009dc1d838 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000ad0f6d13 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 2 locks held by getty/5479: #0: 0000000070097c74 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x27/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000a6e80ff7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21c/0x1a60 drivers/tty/n_tty.c:2156 3 locks held by kworker/0:4/5704: #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000007f2eff54 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x81f/0x1580 kernel/workqueue.c:2240 #1: 000000004a059031 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x853/0x1580 kernel/workqueue.c:2244 #2: 00000000984fc0f7 (&dev->mutex){....}, at: device_lock include/linux/device.h:1207 [inline] #2: 00000000984fc0f7 (&dev->mutex){....}, at: hub_event+0x18a/0x3b00 drivers/usb/core/hub.c:5378 ============================================= 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