INFO: task kworker/0:1:9 blocked for more than 143 seconds. Not tainted 6.6.0-syzkaller-16159-g3ca112b71f35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:22256 pid:9 tgid:9 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:11056 r871xu_dev_remove+0x28e/0x480 drivers/staging/rtl8712/usb_intf.c:596 usb_unbind_interface+0x1dd/0x8d0 drivers/usb/core/driver.c:458 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:2260 hub_port_connect drivers/usb/core/hub.c:5303 [inline] hub_port_connect_change drivers/usb/core/hub.c:5603 [inline] port_event drivers/usb/core/hub.c:5763 [inline] hub_event+0x1be0/0x4f40 drivers/usb/core/hub.c:5845 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 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 INFO: task kworker/1:3:22631 blocked for more than 143 seconds. Not tainted 6.6.0-syzkaller-16159-g3ca112b71f35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 state:D stack:22848 pid:22631 tgid:22631 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_verify_work 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 addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4679 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 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: 6 locks held by kworker/0:1/9: #0: ffff888109671138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9000009fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff888105f1a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105f1a190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5791 #3: ffff888134536190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #3: ffff888134536190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x910 drivers/usb/core/hub.c:2251 #4: ffff8881186b3160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff8881186b3160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8881186b3160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 #5: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: unregister_netdev+0x12/0x30 net/core/dev.c:11056 1 lock held by khungtaskd/29: #0: ffffffff87ead2e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff87ead2e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff87ead2e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 2 locks held by dhcpcd/2435: #0: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x1d3/0x1f00 net/ipv4/devinet.c:1091 #1: ffff888136be4db0 (&padapter->mutex_start){+.+.}-{3:3}, at: netdev_open+0x32/0x820 drivers/staging/rtl8712/os_intfs.c:392 2 locks held by getty/2455: #0: ffff888112aba0a0 (&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 3 locks held by kworker/1:2/5275: #0: ffff888105a41d38 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc900021ffd80 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff888105f02190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105f02190 (&dev->mutex){....}-{3:3}, at: usb_remote_wakeup+0x21/0xe0 drivers/usb/core/hub.c:3788 3 locks held by kworker/0:4/5308: #0: ffff88810ab57538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc90002327d80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4679 6 locks held by kworker/1:9/11414: #0: ffff888109671138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9000f47fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff888105baa190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff888105baa190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5791 #3: ffff888114587190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #3: ffff888114587190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88811db1d160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff88811db1d160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10292 6 locks held by kworker/0:5/13837: 6 locks held by kworker/0:2/19920: #0: ffff888109671138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc90002ba7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff8881057ca190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #2: ffff8881057ca190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5791 #3: ffff8881430f8190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #3: ffff8881430f8190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88810cb7a160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff88810cb7a160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10292 3 locks held by kworker/1:3/22631: #0: ffff88810ab57538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc90001f3fd80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffffffff88fb7768 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4679 4 locks held by udevd/26554: #0: ffff888140847540 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xda/0x1280 fs/seq_file.c:182 #1: ffff888118c38c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4b/0x460 fs/kernfs/file.c:154 #2: ffff88813cd34008 (kn->active#33){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x460 fs/kernfs/file.c:155 #3: ffff888114587190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:997 [inline] #3: ffff888114587190 (&dev->mutex){....}-{3:3}, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143 4 locks held by udevd/26571: #0: ffff88811285dd58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xda/0x1280 fs/seq_file.c:182 #1: ffff8881362de888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4b/0x460 fs/kernfs/file.c:154 #2: ffff888120251918 (kn->active#33){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x460 fs/kernfs/file.c:155 #3: ffff8881430f8190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:997 [inline] #3: ffff8881430f8190 (&dev->mutex){....}-{3:3}, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143 1 lock held by syz-executor.3/30223: #0: ffffffff87eb8d38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #0: ffffffff87eb8d38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x69e/0x7e0 kernel/rcu/tree_exp.h:996 1 lock held by syz-executor.1/30226: #0: ffffffff87eb8d38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #0: ffffffff87eb8d38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:996 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.0-syzkaller-16159-g3ca112b71f35 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 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