INFO: task kworker/1:1:78 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:1 D25376 78 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 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+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:2:95 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D25960 95 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 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+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:0:1807 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:0 D25960 1807 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 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+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:3:1809 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D25624 1809 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 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+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:4:1810 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:4 D25624 1810 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 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+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 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/22: #0: ffffffff87109020 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5331 5 locks held by kworker/1:1/78: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d8ed7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4d6d200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d6d200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881c54ac200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c54ac200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881cd508190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 5 locks held by kworker/0:2/94: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d5cbfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4ca1200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4ca1200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881c9d88200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c9d88200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881c9d8f190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 5 locks held by kworker/1:2/95: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d5f6fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4d8c200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d8c200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881ccff4200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ccff4200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881ccff6190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 1 lock held by rsyslogd/1674: 2 locks held by getty/1764: #0: ffff8881cf67f090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004512e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1765: #0: ffff8881d1acd090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1766: #0: ffff8881cf29a090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000045d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1767: #0: ffff8881cecd5090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1768: #0: ffff8881cf29f090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000046d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1769: #0: ffff8881cf175090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004652e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1770: #0: ffff8881cf678090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000043d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 5 locks held by kworker/1:0/1807: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881cd5bfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4cdf200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4cdf200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881c54ad200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c54ad200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881cd50c190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 5 locks held by kworker/1:3/1809: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881cd54fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4cd8200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4cd8200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881ccff3200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ccff3200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881ccff5190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 5 locks held by kworker/1:4/1810: #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8904d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881cd4a7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4d06200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d06200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881cd1b4200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881cd1b4200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881cd1b7190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 22 Comm: khungtaskd Not tainted 5.6.0-rc3-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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1801 Comm: syz-executor108 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline] RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:193 [inline] RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:969 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0x8d/0xd0 kernel/rcu/tree.c:958 Code: 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 3b 48 8d 7d 68 48 8b 5b 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa <48> c1 ea 03 80 3c 02 00 75 23 48 8b 45 68 48 85 c3 0f 95 c0 65 ff RSP: 0018:ffff8881db209ab0 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff812d3a1c RDX: ffffffff871101e8 RSI: 0000000000000004 RDI: ffffffff871101e8 RBP: ffffffff87110180 R08: ffff8881cf98cb9c R09: ffffed103b646a84 R10: ffffed103b646a83 R11: ffff8881db23541b R12: ffff8881cf98cbb8 R13: 000000000000b8c1 R14: 000000000000b8c1 R15: 0000000000000000 FS: 00000000019d7880(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f10294c0000 CR3: 00000001ce374000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_held_common+0xcb/0x170 kernel/rcu/update.c:98 rcu_read_lock_sched_held+0x5a/0xd0 kernel/rcu/update.c:119 trace_pelt_se_tp include/trace/events/sched.h:620 [inline] trace_pelt_se_tp include/trace/events/sched.h:620 [inline] __update_load_avg_se+0x6f4/0xc00 kernel/sched/pelt.c:298 update_load_avg+0xe30/0x1b60 kernel/sched/fair.c:3603 enqueue_entity kernel/sched/fair.c:4023 [inline] enqueue_task_fair+0x23b/0x23a0 kernel/sched/fair.c:5259 enqueue_task kernel/sched/core.c:1307 [inline] activate_task+0xfb/0x320 kernel/sched/core.c:1329 ttwu_do_activate+0xca/0x130 kernel/sched/core.c:2260 ttwu_queue kernel/sched/core.c:2405 [inline] try_to_wake_up+0xa86/0x1690 kernel/sched/core.c:2639 hrtimer_wakeup+0x43/0x60 kernel/time/hrtimer.c:1769 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x32c/0xd20 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x2e8/0x730 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline] smp_apic_timer_interrupt+0xfe/0x540 arch/x86/kernel/apic/apic.c:1144 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:_raw_spin_unlock_irq+0x27/0x30 kernel/locking/spinlock.c:200 Code: 44 00 00 55 48 8b 74 24 08 48 89 fd 48 8d 7f 18 e8 8e 3f 97 fb 48 89 ef e8 56 21 98 fb e8 b1 a6 b5 fb fb 65 ff 0d 81 10 73 7a <5d> c3 0f 1f 80 00 00 00 00 55 48 89 fd 48 83 c7 18 53 48 89 f3 48 RSP: 0018:ffff8881c6107b38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffff8881cf98e200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffff8881cf98ea4c RBP: ffff8881db234600 R08: ffff8881cf98e200 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881db234600 R13: ffff8881cfa34980 R14: 0000000000000000 R15: 0000000000000001 finish_lock_switch kernel/sched/core.c:3119 [inline] finish_task_switch+0x11d/0x5d0 kernel/sched/core.c:3219 context_switch kernel/sched/core.c:3383 [inline] __schedule+0x89a/0x1d80 kernel/sched/core.c:4080 schedule+0xcd/0x2b0 kernel/sched/core.c:4154 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x21f/0x650 kernel/time/hrtimer.c:1874 hrtimer_nanosleep+0x1df/0x3a0 kernel/time/hrtimer.c:1927 __do_sys_nanosleep kernel/time/hrtimer.c:1961 [inline] __se_sys_nanosleep kernel/time/hrtimer.c:1948 [inline] __x64_sys_nanosleep+0x1dc/0x260 kernel/time/hrtimer.c:1948 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443e40 Code: c0 5b 5d c3 66 0f 1f 44 00 00 8b 04 24 48 83 c4 18 5b 5d c3 66 0f 1f 44 00 00 83 3d f1 5a 29 00 00 75 14 b8 23 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 74 e4 fb ff c3 48 83 ec 08 e8 da 41 00 00 RSP: 002b:00007ffcf1305778 EFLAGS: 00000246 ORIG_RAX: 0000000000000023 RAX: ffffffffffffffda RBX: 00000000000007f8 RCX: 0000000000443e40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffcf1305780 RBP: 00000000000eb0be R08: 0000000000000709 R09: 00000000019d7880 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402740 R13: 00000000004027d0 R14: 0000000000000000 R15: 0000000000000000