INFO: task kworker/1:7:2006 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:7 state:D stack:22744 pid:2006 tgid:2006 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 hub_port_connect drivers/usb/core/hub.c:5465 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/1:2/981: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc900038afbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900038afbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888145f97198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888145f97198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888145fa2518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888145fa2518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888145fa2518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888145fa2518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888145fa2518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 2 locks held by getty/5579: #0: ffff88814dd3a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:5/5878: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000444fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000444fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888145b37198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888145b37198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888145b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888145b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888145b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888145b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888145b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 3 locks held by kworker/0:3/5891: 7 locks held by kworker/u8:16/16704: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:647 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff9a265b18 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:818 #4: ffffffff8e3febe8 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145 #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x29/0x240 mm/pgtable-generic.c:288 #6: ffff88813fe64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #6: ffff88813fe64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:403 5 locks held by kworker/0:7/16760: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90003c8fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90003c8fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888145f39198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888145f39198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888145f3c518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888145f3c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888145f3c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888145f3c518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888145f3c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802985e068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 6 locks held by kworker/0:0/22485: 5 locks held by kworker/1:3/1335: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90012807bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90012807bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888146389198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888146389198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88814638c518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff88814638c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff88814638c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff88814638c518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff88814638c518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff888145f86968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff888145f86968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff888145f86968 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff888145f86968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 5 locks held by kworker/1:4/1686: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90004aafbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90004aafbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888145fae198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888145fae198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888145faf518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888145faf518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888145faf518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888145faf518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888145faf518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802985c468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802985c468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802985c468 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802985c468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 5 locks held by kworker/1:7/2006: #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888142297548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90011387bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90011387bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888145b6e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888145b6e198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888029899518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888029899518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888029899518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888029899518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888029899518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff8880296c4168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: a8 60 02 e9 53 e8 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 67 12 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e207dc0 EFLAGS: 00000242 RAX: 000000000225b4c1 RBX: ffffffff8199570d RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8dcc90a8 RDI: ffffffff8c073980 RBP: ffffffff8e207eb0 R08: ffff8880b86336db R09: 1ffff110170c66db R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8fef1a70 R13: 1ffffffff1c52a78 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000c3b5f18 CR3: 0000000075c36000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1bd/0x500 kernel/sched/idle.c:332 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x380/0x3d0 init/main.c:1206 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147