INFO: task kworker/0:0:9 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:23192 pid:9 tgid:9 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7322 usb_kill_urb drivers/usb/core/urb.c:717 [inline] usb_kill_urb+0x253/0x320 drivers/usb/core/urb.c:703 usb_start_wait_urb+0x2c3/0x580 drivers/usb/core/message.c:74 usb_internal_control_msg drivers/usb/core/message.c:117 [inline] usb_control_msg+0x328/0x4b0 drivers/usb/core/message.c:167 get_bMaxPacketSize0.constprop.0+0xd0/0x1f0 drivers/usb/core/hub.c:4851 hub_port_init+0x642/0x37f0 drivers/usb/core/hub.c:5047 hub_port_connect drivers/usb/core/hub.c:5496 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x2f27/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 5 locks held by kworker/0:0/9: #0: ffff888023691940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297 #1: ffffc900000e7d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298 #2: ffff88802c71f1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #2: ffff88802c71f1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88802c71c568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff88802c71c568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff88802c71c568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff88802c71c568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff88802c71c568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2bd2/0x4af0 drivers/usb/core/hub.c:5953 #4: ffff88802c739260 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802c739260 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802c739260 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802c739260 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2bfb/0x4af0 drivers/usb/core/hub.c:5953 1 lock held by khungtaskd/31: #0: ffffffff8e7e60c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e60c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e7e60c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by syslogd/4960: #0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:675 [inline] #0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:659 #1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:218 [inline] #1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2e8e/0x6730 kernel/sched/core.c:7222 2 locks held by getty/8893: #0: ffff88823bf8c8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000f48b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211 ============================================= 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 05/09/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 27853 Comm: syz.9.6004 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:124 [inline] RIP: 0010:lock_is_held_type+0x42/0x140 kernel/locking/lockdep.c:5933 Code: 8b 15 d2 75 78 08 85 d2 0f 85 de 00 00 00 41 57 41 56 41 55 41 54 55 53 48 83 ec 08 65 48 8b 2d fc 2e 78 08 8b 95 9c 0b 00 00 <85> d2 0f 85 a7 00 00 00 48 89 fb 41 89 f4 9c 41 5d fa 48 c7 c7 8a RSP: 0000:ffffc90007e67d48 EFLAGS: 00000096 RAX: 00000000ffffffff RBX: ffff88807a7ab300 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff8880b8428418 RBP: ffff888027a60000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880b8428400 R14: 0000000000000001 R15: 0000000000000000 FS: 000055558e83d500(0000) GS:ffff8881242e7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2eafcff8 CR3: 00000000435d7000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000007 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] __remove_hrtimer+0x374/0x440 kernel/time/hrtimer.c:1145 __run_hrtimer kernel/time/hrtimer.c:2012 [inline] __hrtimer_run_queues+0x352/0x9c0 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0033:0x7f0b5ac6d304 Code: 48 0f 7e ca 48 39 c2 73 65 48 39 f0 0f 82 2a 01 00 00 48 39 f2 72 65 66 0f c6 c0 01 0f 11 45 00 4c 89 e6 eb 09 90 48 8b 4b 08 <48> 83 c3 08 48 39 d1 72 f3 48 8d 46 f8 48 8b 76 f8 48 39 f2 73 13 RSP: 002b:00007ffd87b0b470 EFLAGS: 00000293 RAX: 00007f0b5ab04a20 RBX: 00007f0b5a950ff8 RCX: ffffffff84b336da RDX: ffffffff89642b14 RSI: 00007f0b5ab04a20 RDI: 00007f0b5a9f7000 RBP: 00007f0b5a7f7008 R08: 00007f0b5b000000 R09: 00007f0b5b016038 R10: 0000000000000001 R11: 000000000000000c R12: 00007f0b5abf7000 R13: 0000000000000023 R14: 000000000007ffff R15: 0000000000000001