imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10491 ticks this GP) idle=f93/1/0x4000000000000000 softirq=15593/15593 fqs=5247 (t=10501 jiffies g=21373 q=18846) NMI backtrace for cpu 1 CPU: 1 PID: 1108 Comm: kworker/1:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x6d8/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 ae 4b cb f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 36 d5 9e f7 65 8b 05 17 d3 4f 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90000dd0820 EFLAGS: 00000206 RAX: da7c5fae5ac12600 RBX: 0000000000000a02 RCX: da7c5fae5ac12600 RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: 0000000000000001 RBP: ffffc90000dd08b0 R08: dffffc0000000000 R09: fffffbfff1ff7a40 R10: fffffbfff1ff7a40 R11: 1ffffffff1ff7a3f R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888023ca8000 R15: 1ffff920001ba104 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] dummy_timer+0x2cde/0x2e10 drivers/usb/gadget/udc/dummy_hcd.c:-1 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_call_function_single arch/x86/kernel/smp.c:243 [inline] sysvec_call_function_single+0x9d/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:684 RIP: 0010:check_region_inline mm/kasan/generic.c:172 [inline] RIP: 0010:kasan_check_range+0x13/0x290 mm/kasan/generic.c:189 Code: ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 41 56 53 49 89 f8 <49> 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f 41 81 f8 ff ff 01 RSP: 0018:ffffc900049374e0 EFLAGS: 00000202 RAX: ffff8880210d9e01 RBX: ffffffff8c24d3c8 RCX: ffffffff815b8221 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8c24d3c8 RBP: 0000000000000008 R08: ffffffff8c24d3c8 R09: ffffed100421b3b9 R10: ffffed100421b3b9 R11: 1ffff1100421b3b8 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff8c24d3c8 R15: 1ffffffff1849a78 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_long_read include/linux/atomic/atomic-instrumented.h:1183 [inline] rwsem_owner_flags kernel/locking/rwsem.c:287 [inline] rwsem_spin_on_owner+0x31/0x2e0 kernel/locking/rwsem.c:735 rwsem_optimistic_spin kernel/locking/rwsem.c:821 [inline] rwsem_down_write_slowpath+0x538/0x11f0 kernel/locking/rwsem.c:1082 kernfs_add_one+0x52/0x6c0 fs/kernfs/dir.c:747 kernfs_create_link+0x160/0x200 fs/kernfs/symlink.c:49 sysfs_do_create_link_sd+0x83/0x110 fs/sysfs/symlink.c:44 usb_new_device+0xf58/0x1640 drivers/usb/core/hub.c:2644 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored