INFO: task kworker/0:3:5228 blocked for more than 143 seconds. Not tainted 6.12.0-rc6-syzkaller-00143-gaa03bda68af7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:21888 pid:5228 tgid:5228 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x1042/0x34b0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 unregister_netdev+0x12/0x30 net/core/dev.c:11486 r871xu_dev_remove+0x291/0x480 drivers/staging/rtl8712/usb_intf.c:596 usb_unbind_interface+0x1e2/0x960 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] device_remove+0x122/0x170 drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296 bus_remove_device+0x22f/0x420 drivers/base/bus.c:576 device_del+0x396/0x9f0 drivers/base/core.c:3861 usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2304 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 6 locks held by kworker/0:0/8: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000008fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810af91190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810af91190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff8881062d5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8881062d5190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff8881124be160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8881124be160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10630 6 locks held by kworker/0:1/9: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000009fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810af11190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810af11190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88811c916190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88811c916190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff888119ff1160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff888119ff1160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10630 1 lock held by khungtaskd/30: #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 6 locks held by kworker/1:1/41: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc900002b7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810abc1190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810abc1190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88810bbf9190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88810bbf9190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88810bbb6160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88810bbb6160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10630 2 locks held by dhcpcd/2898: #0: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x26e/0x1e20 net/ipv4/devinet.c:1112 #1: ffff888132ac4da8 (&padapter->mutex_start){+.+.}-{3:3}, at: netdev_open+0x32/0x870 drivers/staging/rtl8712/os_intfs.c:392 2 locks held by getty/2918: #0: ffff888108aaf0a0 (&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+0xfba/0x1480 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:3/5228: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90004c8fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810af41190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810af41190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88810bbfe190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88810bbfe190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff88810f7fd160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88810f7fd160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88810f7fd160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffffffff8a19cbe8 ( rtnl_mutex){+.+.}-{3:3}, at: unregister_netdev+0x12/0x30 net/core/dev.c:11486 6 locks held by kworker/1:3/5242: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90004cffd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810af29190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810af29190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88811e001190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88811e001190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88811ac84160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88811ac84160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10630 4 locks held by udevd/5272: #0: ffff88811319c0a0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888131ccc488 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888112d85f08 (kn->active#3){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811c916190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88811c916190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736 4 locks held by udevd/5547: #0: ffff88811964e418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff8881140b6888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881073d7968 (kn->active#3){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810af29190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88810af29190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736 3 locks held by kworker/1:0/8561: #0: ffff888100081948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90010dffd80 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x84/0x1130 net/wireless/reg.c:2480 3 locks held by kworker/u8:1/8728: #0: ffff888111e6b148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9001108fd80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffffffff8a19cbe8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4736 1 lock held by syz.4.2164/12374: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00143-gaa03bda68af7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111