INFO: task kworker/0:7:5608 blocked for more than 143 seconds. Not tainted 6.7.0-rc5-syzkaller-g8be0c877fb3b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:7 state:D stack:22400 pid:5608 tgid:5608 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xc71/0x3050 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe7/0x270 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x969/0x1340 kernel/locking/mutex.c:747 unregister_netdev+0x12/0x30 net/core/dev.c:11113 r871xu_dev_remove+0x28e/0x480 drivers/staging/rtl8712/usb_intf.c:596 usb_unbind_interface+0x1dd/0x8d0 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:569 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1295 bus_remove_device+0x22c/0x420 drivers/base/bus.c:574 device_del+0x39a/0xa50 drivers/base/core.c:3814 usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1416 usb_disconnect+0x2e1/0x910 drivers/usb/core/hub.c:2257 hub_port_connect drivers/usb/core/hub.c:5305 [inline] hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] port_event drivers/usb/core/hub.c:5765 [inline] hub_event+0x1be0/0x4f40 drivers/usb/core/hub.c:5847 process_one_work+0x884/0x15c0 kernel/workqueue.c:2627 process_scheduled_works kernel/workqueue.c:2700 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2781 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 3 locks held by kworker/0:1/9: #0: ffff888105a41d38 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc9000009fd80 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffff888105f42190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105f42190 (&dev->mutex){....}-{3:3}, at: usb_remote_wakeup+0x21/0xe0 drivers/usb/core/hub.c:3785 3 locks held by kworker/1:1/26: #0: ffff88810a37e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc900001c7d80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffffffff88facae8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4679 1 lock held by khungtaskd/29: #0: ffffffff87ead320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff87ead320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff87ead320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by dhcpcd/2434: #0: ffffffff88facae8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x1d3/0x1f00 net/ipv4/devinet.c:1091 #1: ffff888141134db0 (&padapter->mutex_start){+.+.}-{3:3}, at: netdev_open+0x32/0x820 drivers/staging/rtl8712/os_intfs.c:392 2 locks held by getty/2454: #0: ffff888112a5a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201 6 locks held by kworker/0:3/5275: 6 locks held by kworker/0:5/5357: #0: ffff888108a78d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc9000c8e7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffff888106362190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888106362190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5793 #3: ffff888142510190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #3: ffff888142510190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff888107e51160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff888107e51160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff88facae8 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10348 3 locks held by kworker/0:6/5477: #0: ffff88810a37e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc9000254fd80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffffffff88facae8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4679 6 locks held by kworker/0:7/5608: #0: ffff888108a78d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc9000cd57d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffff888105f52190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105f52190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5793 #3: ffff888117b57190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #3: ffff888117b57190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x910 drivers/usb/core/hub.c:2248 #4: ffff8881196f4160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff8881196f4160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8881196f4160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 #5: ffffffff88facae8 (rtnl_mutex){+.+.}-{3:3}, at: unregister_netdev+0x12/0x30 net/core/dev.c:11113 3 locks held by kworker/1:7/5920: #0: ffff888108a78d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2602 #1: ffffc9000d2bfd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2603 #2: ffff888105fd2190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105fd2190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5793 4 locks held by udevd/8093: #0: ffff88811533de80 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xda/0x1280 fs/seq_file.c:182 #1: ffff88810ef73c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4b/0x460 fs/kernfs/file.c:154 #2: ffff88810a782830 (kn->active#28){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x460 fs/kernfs/file.c:155 #3: ffff888142510190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:997 [inline] #3: ffff888142510190 (&dev->mutex){....}-{3:3}, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc5-syzkaller-g8be0c877fb3b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x26c/0x2d0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1b/0x20 drivers/acpi/processor_idle.c:112