rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2660 jiffies s: 7021 root: 0x2/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 0 to CPUs 1: cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes NMI backtrace for cpu 1 CPU: 1 PID: 5599 Comm: syz-executor.4 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:413 Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 5c 8c bf fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7 RSP: 0018:ffffc90000a17190 EFLAGS: 00000002 RAX: 0000000000000020 RBX: ffffffff94ace200 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff853c4a5b R09: 1ffff11003f92046 R10: dffffc0000000000 R11: ffffffff853c4a10 R12: dffffc0000000000 R13: 0000000000000020 R14: 0000000000000020 R15: 00000000000003f8 FS: 0000000000000000(0000) GS:ffff8880b9500000(0063) knlGS:00000000f5e63b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000030431000 CR3: 0000000028952000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_write+0x1212/0x1770 drivers/tty/serial/8250/8250_port.c:3393 console_emit_next_record kernel/printk/printk.c:2928 [inline] console_flush_all+0x865/0xfd0 kernel/printk/printk.c:2994 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063 vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345 dev_vprintk_emit+0x2ae/0x330 drivers/base/core.c:4951 dev_printk_emit+0xdd/0x120 drivers/base/core.c:4962 _dev_err+0x122/0x170 drivers/base/core.c:5017 wdm_int_callback+0x45c/0xac0 drivers/usb/class/cdc-wdm.c:276 __usb_hcd_giveback_urb+0x373/0x530 drivers/usb/core/hcd.c:1648 dummy_timer+0x830/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1987 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:stack_trace_consume_entry+0x5/0x280 kernel/stacktrace.c:83 Code: ff ff ff e8 5d 66 04 0a 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 18 48 89 fb 48 ba 00 00 00 00 RSP: 0018:ffffc90000a181f0 EFLAGS: 00000286 RAX: 0000000000000504 RBX: ffffffff81fb9f87 RCX: ffff888021d9bc00 RDX: 0000000000000504 RSI: ffffffff81fb9f87 RDI: ffffc90000a182e0 RBP: ffffc90000a18290 R08: ffffffff81376382 R09: ffffffff8140f8cf R10: 0000000000000003 R11: ffffffff8181cfd0 R12: ffff888021d9bc00 R13: ffffffff8181cfd0 R14: ffffc90000a182e0 R15: ffffc90000a18200 arch_stack_walk+0x143/0x1b0 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2195 [inline] slab_free mm/slub.c:4436 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4511 ifb_xmit+0x1f0/0x5f0 drivers/net/ifb.c:346 __netdev_start_xmit include/linux/netdevice.h:4882 [inline] netdev_start_xmit include/linux/netdevice.h:4896 [inline] xmit_one net/core/dev.c:3578 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3594 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3807 [inline] __dev_queue_xmit+0x1a24/0x3d30 net/core/dev.c:4359 lapb_data_transmit+0x91/0xb0 net/lapb/lapb_iface.c:447 lapb_transmit_buffer+0x168/0x1f0 net/lapb/lapb_out.c:149 lapb_t1timer_expiry+0x6b8/0xb20 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 ee c3 6a f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 c3 77 d4 f5 65 8b 05 f4 c1 72 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90002f4f440 EFLAGS: 00000206 RAX: aa8dc7ed780bd600 RBX: 1ffff920005e9e8c RCX: ffffffff8172c78a RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: 0000000000000001 RBP: ffffc90002f4f4e0 R08: ffffffff92fa865f R09: 1ffffffff25f50cb R10: dffffc0000000000 R11: fffffbfff25f50cc R12: dffffc0000000000 R13: 1ffff920005e9e88 R14: ffffc90002f4f460 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] dummy_urb_enqueue+0x59c/0x760 drivers/usb/gadget/udc/dummy_hcd.c:1310 usb_hcd_submit_urb+0x36c/0x1e80 drivers/usb/core/hcd.c:1533 wdm_open+0x324/0x550 drivers/usb/class/cdc-wdm.c:741 usb_open+0x225/0x300 drivers/usb/core/file.c:47 chrdev_open+0x5b0/0x630 fs/char_dev.c:414 do_dentry_open+0x95a/0x1720 fs/open.c:955 do_open fs/namei.c:3650 [inline] path_openat+0x289f/0x3280 fs/namei.c:3807 do_filp_open+0x235/0x490 fs/namei.c:3834 do_sys_openat2+0x13e/0x1d0 fs/open.c:1405 do_sys_open fs/open.c:1420 [inline] __do_compat_sys_openat fs/open.c:1480 [inline] __se_compat_sys_openat fs/open.c:1478 [inline] __ia32_compat_sys_openat+0x23f/0x290 fs/open.c:1478 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf73da579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5e63150 EFLAGS: 00000206 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000f5e631a0 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 00000000f73caff4 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71 cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:1.0: nonzero urb status received: -71