imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: 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 rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (6833 ticks this GP) idle=dff/1/0x4000000000000000 softirq=8338/8338 fqs=5 (t=10501 jiffies g=8893 q=1855) NMI backtrace for cpu 0 CPU: 0 PID: 4754 Comm: udevd Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 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 2e 47 cc 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 f6 d4 9f f7 65 8b 05 97 d4 50 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90000007820 EFLAGS: 00000206 RAX: 3ee28c93f28b5c00 RBX: 0000000000000a02 RCX: 3ee28c93f28b5c00 RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: 0000000000000001 RBP: ffffc900000078b0 R08: dffffc0000000000 R09: fffffbfff1ff6e41 R10: fffffbfff1ff6e41 R11: 1ffffffff1ff6e40 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888023884000 R15: 1ffff92000000f04 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_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:seqcount_lockdep_reader_access+0x17a/0x1c0 include/linux/seqlock.h:106 Code: ff 4d 85 ed 75 16 e8 a5 4d ad ff eb 15 e8 9e 4d ad ff e8 f9 b6 dd 07 4d 85 ed 74 ea e8 8f 4d ad ff fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc900030bf7a0 EFLAGS: 00000293 RAX: ffffffff81ca7691 RBX: 0000000000000000 RCX: ffff88802b420000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900030bf850 R08: dffffc0000000000 R09: fffffbfff1ad2dd6 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: dffffc0000000000 R13: 0000000000000200 R14: ffffffff81ca7c7e R15: 1ffff92000617ef4 set_root+0x15e/0x3a0 fs/namei.c:942 nd_jump_root+0x2a7/0x410 fs/namei.c:963 path_init+0x382/0x1160 fs/namei.c:2365 path_openat+0x18a/0x2f30 fs/namei.c:3737 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fe4d423a407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe2ae0f7a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe4d414c880 RCX: 00007fe4d423a407 RDX: 0000000000080000 RSI: 00005611acbe70f0 RDI: ffffffffffffff9c RBP: 00005611acbfdca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe2ae1ff60 R13: 00000000000000e1 R14: 0000561197eb500c R15: 0000000000000000 imon 3-1:0.0: 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 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 3-1:0.0: 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 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: 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 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored