INFO: task kworker/1:2:102 blocked for more than 143 seconds. Not tainted 5.3.0-rc2+ #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D22936 102 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0x9a/0x250 kernel/sched/core.c:3944 rwsem_down_write_slowpath+0x781/0xef0 kernel/locking/rwsem.c:1214 __down_write kernel/locking/rwsem.c:1365 [inline] down_write+0x13c/0x150 kernel/locking/rwsem.c:1501 usb_deregister_dev drivers/usb/core/file.c:238 [inline] usb_deregister_dev+0x61/0x270 drivers/usb/core/file.c:230 sisusb_disconnect+0x5a/0x1a0 drivers/usb/misc/sisusbvga/sisusb.c:3166 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1120 [inline] device_release_driver_internal+0x404/0x4c0 drivers/base/dd.c:1151 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556 device_del+0x420/0xb10 drivers/base/core.c:2288 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199 hub_port_connect drivers/usb/core/hub.c:4949 [inline] hub_port_connect_change drivers/usb/core/hub.c:5213 [inline] port_event drivers/usb/core/hub.c:5359 [inline] hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 process_scheduled_works kernel/workqueue.c:2331 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417 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: 0000000079768fa0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5254 6 locks held by kworker/1:2/102: #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: 00000000e6347ac3 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: 0000000023c3c53d (&dev->mutex){....}, at: device_lock include/linux/device.h:1220 [inline] #2: 0000000023c3c53d (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387 #3: 000000003bb388ea (&dev->mutex){....}, at: device_lock include/linux/device.h:1220 [inline] #3: 000000003bb388ea (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190 #4: 00000000eb0f5ca9 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x4c0 drivers/base/dd.c:1148 #5: 000000009e7572a4 (minor_rwsem#2){++++}, at: usb_deregister_dev drivers/usb/core/file.c:238 [inline] #5: 000000009e7572a4 (minor_rwsem#2){++++}, at: usb_deregister_dev+0x61/0x270 drivers/usb/core/file.c:230 1 lock held by rsyslogd/1606: #0: 00000000dd78c226 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1696: #0: 00000000d3f6f9de (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000006af6ea5f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1697: #0: 0000000045a72721 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000990c009f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1698: #0: 00000000a0081f38 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000004bcf5387 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1699: #0: 0000000013db4cf8 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000084e41b85 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1700: #0: 000000000be7b69c (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000a7d76e8a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1701: #0: 00000000d846bd3c (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000005675e0fa (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1702: #0: 000000006b68e621 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000006e2ebe3e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 5 locks held by kworker/0:6/2884: #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 00000000ee5a5b88 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: 00000000f3fd34e5 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: 0000000053de1c95 (&dev->mutex){....}, at: device_lock include/linux/device.h:1220 [inline] #2: 0000000053de1c95 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387 #3: 000000006ef8a516 (&dev->mutex){....}, at: device_lock include/linux/device.h:1220 [inline] #3: 000000006ef8a516 (&dev->mutex){....}, at: __device_attach+0x7b/0x360 drivers/base/dd.c:859 #4: 0000000083063824 (&dev->mutex){....}, at: device_lock include/linux/device.h:1220 [inline] #4: 0000000083063824 (&dev->mutex){....}, at: __device_attach+0x7b/0x360 drivers/base/dd.c:859 2 locks held by syz-executor.5/12185: #0: 000000009e7572a4 (minor_rwsem#2){++++}, at: usb_open+0x23/0x270 drivers/usb/core/file.c:39 #1: 0000000060719e89 (&(sisusb->lock)){+.+.}, at: sisusb_open+0xae/0x430 drivers/usb/misc/sisusbvga/sisusb.c:2396 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.3.0-rc2+ #25 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+0xca/0x13e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 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+0x9a4/0xe50 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0x28/0x2e0 arch/x86/kernel/process.c:580