INFO: task kworker/0:7:7558 blocked for more than 143 seconds. Not tainted 6.14.0-rc3-syzkaller-00037-gc749f058b437 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:7 state:D stack:22048 pid:7558 tgid:7558 ppid:2 task_flags:0x4288060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x113d/0x35d0 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 rtnl_net_lock include/linux/rtnetlink.h:129 [inline] unregister_netdev+0x17/0x30 net/core/dev.c:11885 usbnet_disconnect+0x109/0x500 drivers/net/usb/usbnet.c:1637 usb_unbind_interface+0x1da/0x9a0 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:579 device_del+0x396/0x9f0 drivers/base/core.c:3854 usb_disable_device+0x368/0x7e0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2316 hub_port_connect drivers/usb/core/hub.c:5373 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5915 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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/0:1/9: #0: ffff888105ebf948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000009fd18 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810af8a198 ( &dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1030 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5861 #3: ffff8881052ac198 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] ){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88811b8b1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff88811b8b1160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a1a0ba8 ( rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:144 [inline] rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:10971 1 lock held by khungtaskd/30: #0: ffffffff88ebe480 (rcu_read_lock){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] , at: rcu_read_lock include/linux/rcupdate.h:849 [inline] , at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:6/1109: #0: ffff888111cbe148 ((wq_completion)ipv6_addrconf ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90001dbfd18 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8a1a0ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8a1a0ba8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4730 5 locks held by kworker/0:2/1110: #0: ffff888105ebf948 ((wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90001e8fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff8881093c2198 ( &dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1030 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5861 #3: ffff8881349a6198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88811428f160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] ffff88811428f160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 2 locks held by dhcpcd/2882: 2 locks held by getty/2902: #0: ffff8881121e20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 7 locks held by kworker/0:3/5228: #0: ffff8881f583d2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:598 [inline] (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1521 [inline] (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1852 [inline] (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x28d/0x35d0 kernel/sched/core.c:6688 #1: ffffc90001f4fd18 ((work_completion)(&(&d->rc_query_work)->work) #2){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff8881f582a318 ( &base->lock ){-.-.}-{2:2}, at: lock_timer_base+0x12f/0x1e0 kernel/time/timer.c:1046 #3: ffffffff93626738 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x149/0x4a0 lib/debugobjects.c:818 #4: ffffffff93542258 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x149/0x4a0 lib/debugobjects.c:818 #5: ffffffff88dcb8f8 (console_owner_lock){..-.}-{2:2}, at: console_lock_spinning_disable_and_check+0x78/0x180 kernel/printk/printk.c:1963 #6: ffffffff9366d278 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] (&port_lock_key){-.-.}-{3:3}, at: serial8250_console_write+0x17c/0x1870 drivers/tty/serial/8250/8250_port.c:3424 4 locks held by udevd/5236: #0: ffff8881118ced58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888114712488 (&of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881073e1e18 (kn->active#4 ){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810af8a198 ( &dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] &dev->mutex){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 6 locks held by kworker/0:6/5462: #0: ffff888105ebf948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc900054bfd18 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810abcf198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1030 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5861 #3: ffff88810ef61198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff888116b3a160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff888116b3a160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8a1a0ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:144 [inline] ffffffff8a1a0ba8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:10971 6 locks held by kworker/0:7/7558: #0: ffff888105ebf948 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc900018e7d18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810aff5198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1030 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5861 #3: ffff88811bea5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2307 #4: ffff8881082dd160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffffffff8a1a0ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdev+0x17/0x30 net/core/dev.c:11885 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc3-syzkaller-00037-gc749f058b437 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5228 Comm: kworker/0:3 Not tainted 6.14.0-rc3-syzkaller-00037-gc749f058b437 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:preempt_count_add+0x1a/0x150 kernel/sched/core.c:5860 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 c7 c0 e0 19 4e 93 55 48 ba 00 00 00 00 00 fc ff df 48 89 c1 53 <83> e0 07 89 fb 48 c1 e9 03 83 c0 03 65 01 3d cb ad b6 7e 0f b6 14 RSP: 0018:ffffc90000007e08 EFLAGS: 00000046 RAX: ffffffff934e19e0 RBX: ffff8881f582c480 RCX: ffffffff934e19e0 RDX: dffffc0000000000 RSI: ffffffff81689e96 RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000007 R12: ffffc900016f7d78 R13: ffff8881f582c500 R14: ffff8881f582c480 R15: ffffffff81687a90 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000559855299b58 CR3: 0000000116700000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:118 [inline] _raw_spin_lock_irq+0x1a/0x50 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1805 [inline] __hrtimer_run_queues+0x2be/0xae0 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x8b/0xb0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x621/0x6f0 kernel/printk/printk.c:2431 Code: 85 ed 0f 85 81 00 00 00 e8 ec e3 1f 00 9c 41 5c 41 81 e4 00 02 00 00 31 ff 4c 89 e6 e8 08 df 1f 00 4d 85 e4 0f 85 8d 00 00 00 ca e3 1f 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc90001f4f1f8 EFLAGS: 00000287 RAX: 0000000000076042 RBX: 0000000000000064 RCX: ffffc9001480f000 RDX: 0000000000100000 RSI: ffffffff815b5348 RDI: 0000000000000007 RBP: 1ffff920003e9e41 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000006 R12: 0000000000000000 R13: 0000000000000200 R14: ffff888101e957c0 R15: ffffc90001f4f2c0 dev_vprintk_emit drivers/base/core.c:4890 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4901 __dev_printk+0xf5/0x270 drivers/base/core.c:4913 _dev_info+0xe5/0x120 drivers/base/core.c:4959 usb_serial_device_remove+0x17e/0x280 drivers/usb/serial/bus.c:99 device_remove+0xc8/0x170 drivers/base/dd.c:567 __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:579 device_del+0x396/0x9f0 drivers/base/core.c:3854 usb_serial_disconnect+0x232/0x4e0 drivers/usb/serial/usb-serial.c:1203 usb_unbind_interface+0x1da/0x9a0 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:579 device_del+0x396/0x9f0 drivers/base/core.c:3854 usb_disable_device+0x368/0x7e0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2316 hub_port_connect drivers/usb/core/hub.c:5373 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5915 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244