INFO: task kworker/1:2:83 blocked for more than 143 seconds. Not tainted 5.6.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D25696 83 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 flush_workqueue+0x40a/0x14c0 kernel/workqueue.c:2829 ath6kl_usb_destroy+0x2e/0x190 drivers/net/wireless/ath/ath6kl/usb.c:609 ath6kl_usb_probe+0xe8a/0x1180 drivers/net/wireless/ath/ath6kl/usb.c:1166 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_set_configuration+0xece/0x1840 drivers/usb/core/message.c:2025 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2266 process_scheduled_works kernel/workqueue.c:2328 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2414 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:2:95 blocked for more than 143 seconds. Not tainted 5.6.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D25600 95 2 0x80004000 Workqueue: events request_firmware_work_func 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 device_lock include/linux/device.h:771 [inline] ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1077 [inline] ath9k_hif_usb_firmware_cb+0x37c/0x500 drivers/net/wireless/ath/ath9k/hif_usb.c:1210 request_firmware_work_func+0x126/0x242 drivers/base/firmware_loader/main.c:976 process_one_work+0x94b/0x1620 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 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/0:5:3113 blocked for more than 143 seconds. Not tainted 5.6.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:5 D24816 3113 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 flush_workqueue+0x40a/0x14c0 kernel/workqueue.c:2829 ath6kl_usb_destroy+0x2e/0x190 drivers/net/wireless/ath/ath6kl/usb.c:609 ath6kl_usb_probe+0xe8a/0x1180 drivers/net/wireless/ath/ath6kl/usb.c:1166 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_set_configuration+0xece/0x1840 drivers/usb/core/message.c:2025 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2266 process_scheduled_works kernel/workqueue.c:2328 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2414 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:6:3117 blocked for more than 144 seconds. Not tainted 5.6.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:6 D26088 3117 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 flush_workqueue+0x40a/0x14c0 kernel/workqueue.c:2829 hif_detach_htc drivers/net/wireless/ath/ath6kl/usb.c:856 [inline] ath6kl_usb_power_off+0x33/0x40 drivers/net/wireless/ath/ath6kl/usb.c:1055 ath6kl_hif_power_off drivers/net/wireless/ath/ath6kl/hif-ops.h:143 [inline] ath6kl_core_init drivers/net/wireless/ath/ath6kl/core.c:255 [inline] ath6kl_core_init+0x236/0x10d0 drivers/net/wireless/ath/ath6kl/core.c:66 ath6kl_usb_probe+0xc7a/0x1180 drivers/net/wireless/ath/ath6kl/usb.c:1155 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_set_configuration+0xece/0x1840 drivers/usb/core/message.c:2025 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2500 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 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: 5 locks held by kworker/0:0/5: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881da1dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4d7e200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d7e200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881cf36a200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881cf36a200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881cf36c190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881cf36c190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 1 lock held by khungtaskd/23: #0: ffffffff87108b60 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5331 5 locks held by kworker/1:2/83: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881d8a77dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4da5200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4da5200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881c8bb0200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c8bb0200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881c8bb4190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881c8bb4190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 3 locks held by kworker/0:2/95: #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881da028d28 ((wq_completion)events){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881d5cc7dd0 ((work_completion)(&fw_work->work)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4d08200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d08200 (&dev->mutex){....}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1077 [inline] #2: ffff8881d4d08200 (&dev->mutex){....}, at: ath9k_hif_usb_firmware_cb+0x37c/0x500 drivers/net/wireless/ath/ath9k/hif_usb.c:1210 5 locks held by kworker/0:3/167: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881cd9a7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4d0f200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d0f200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d54e3200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881d54e3200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881a9def190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881a9def190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 1 lock held by in:imklog/260: 2 locks held by agetty/258: #0: ffff8881d6a04090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900001632e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 5 locks held by kworker/0:4/3111: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881c5447dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4ce1200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4ce1200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881a9dea200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881a9dea200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881d13ef190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881d13ef190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 5 locks held by kworker/0:5/3113: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881c8e17dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4caa200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4caa200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881ab07f200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ab07f200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881c84f7190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881c84f7190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 5 locks held by kworker/0:6/3117: #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d83928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2237 #1: ffff8881c5597dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2241 #2: ffff8881d4d08200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d08200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881cc552200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881cc552200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881cc557190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881cc557190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.6.0-rc7-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: 374 Comm: syz-executor.2 Not tainted 5.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x162/0x3b60 kernel/locking/lockdep.c:3860 Code: c0 74 08 3c 03 0f 8e ca 16 00 00 48 c7 c2 20 fc 69 89 8b 9d 48 08 00 00 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 <48> c7 c0 20 fc 69 89 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 d1 RSP: 0018:ffff8881ad8979f8 EFLAGS: 00000806 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff8881db234620 RBP: ffff8881d8d41880 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff0fcc538 R11: ffffffff87e629c7 R12: ffffffff89334310 R13: 0000000000000000 R14: ffff8881db234618 R15: 0000000000000000 FS: 00000000013fd940(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1710efc008 CR3: 00000001ad801000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x130/0x340 kernel/locking/lockdep.c:4484 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x27/0x40 kernel/locking/spinlock.c:151 rq_lock kernel/sched/sched.h:1215 [inline] __schedule+0x21c/0x1d80 kernel/sched/core.c:4028 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: 0033:0x45ad20 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 31 dc 82 00 00 75 14 b8 23 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 d4 d1 fb ff c3 48 83 ec 08 e8 ea 46 00 00 RSP: 002b:00007ffe8026a338 EFLAGS: 00000246 ORIG_RAX: 0000000000000023 RAX: ffffffffffffffda RBX: 0000000000032bdf RCX: 000000000045ad20 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffe8026a340 RBP: 00000000000000c8 R08: 0000000000000001 R09: 00000000013fd940 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe8026a390 R14: 0000000000032bdf R15: 00007ffe8026a3a0