rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=61a/1/0x4000000000000000 softirq=118944/118956 fqs=5020 (t=10500 jiffies g=182273 q=141361) NMI backtrace for cpu 1 CPU: 1 PID: 25104 Comm: syz-executor.4 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3637 [inline] rcu_sched_clock_irq.cold+0x5b3/0xccd kernel/rcu/tree.c:2519 update_process_times+0x25/0xa0 kernel/time/timer.c:1710 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1524 [inline] __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191 Code: 48 c7 c0 88 34 b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d 83 f8 c1 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 e5 84 5b f9 65 8b 05 5e c2 0d 78 RSP: 0018:ffffc90000da8ca8 EFLAGS: 00000282 RAX: 1ffffffff136c691 RBX: 0000000000000282 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000282 RBP: ffff8880a5fad108 R08: 0000000000000001 R09: ffffffff8c5edaef R10: fffffbfff18bdb5d R11: 0000000000000000 R12: ffff888046067d40 R13: ffff8880a5fad108 R14: ffff8880a5fad0f0 R15: ffff8880ae7255c0 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline] skb_dequeue+0x125/0x180 net/core/skbuff.c:3040 mrp_queue_xmit net/802/mrp.c:350 [inline] mrp_join_timer+0x97/0xc0 net/802/mrp.c:595 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755 __run_timers kernel/time/timer.c:1736 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1768 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191 Code: 48 c7 c0 88 34 b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d 83 f8 c1 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 e5 84 5b f9 65 8b 05 5e c2 0d 78 RSP: 0018:ffffc90017f178e0 EFLAGS: 00000282 RAX: 1ffffffff136c691 RBX: 0000000000000282 RCX: 1ffffffff1563891 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000282 RBP: ffffffff8cb413c8 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a2c8a7f8 R13: 1ffff92002fe2f2e R14: ffffffff8cb413c8 R15: ffffffff8cb413c0 __debug_object_init+0x401/0xce0 lib/debugobjects.c:580 debug_object_init lib/debugobjects.c:595 [inline] debug_object_activate+0x32c/0x3e0 lib/debugobjects.c:681 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu kernel/rcu/tree.c:2880 [inline] call_rcu+0x2c/0x7e0 kernel/rcu/tree.c:2968 task_work_run+0xdd/0x190 kernel/task_work.c:135 exit_task_work include/linux/task_work.h:25 [inline] do_exit+0xb7d/0x29f0 kernel/exit.c:806 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x40b/0x1ee0 kernel/signal.c:2743 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:135 [inline] exit_to_user_mode_prepare+0x15d/0x1c0 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d239 Code: Bad RIP value. RSP: 002b:00007ff27bcc6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000005 RBX: 000000000000ff00 RCX: 000000000045d239 RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000004 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 000000000169fb6f R14: 00007ff27bcc79c0 R15: 000000000118cf4c