rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=dd6/1/0x4000000000000004 softirq=26038/26517 fqs=5197 (t=10500 jiffies g=16765 q=573) NMI backtrace for cpu 1 CPU: 1 PID: 14748 Comm: syz-executor.2 Not tainted 5.4.0-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq.cold+0x509/0xc02 kernel/rcu/tree.c:2271 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:batadv_dat_snoop_outgoing_dhcp_ack+0x0/0x390 net/batman-adv/distributed-arp-table.c:1776 Code: 89 55 d0 e8 d2 ab 55 fa 48 8b 55 d0 e9 66 fd ff ff e8 e4 ab 55 fa e9 1f fd ff ff 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 41 57 41 56 4c 8d 75 d8 41 55 49 89 f5 41 54 49 89 fc RSP: 0018:ffff88807ec093c0 EFLAGS: 00010206 ORIG_RAX: ffffffffffffff13 RAX: ffff88805d640540 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 000000000000dd86 RSI: ffff88807a943dc0 RDI: ffff88807b1c4b80 RBP: ffff88807ec094d8 R08: ffff88805d640540 R09: ffffed100ea41da6 R10: ffffed100ea41da5 R11: ffff88807520ed2b R12: ffff88807d88b002 R13: ffff88807b1c4000 R14: 000000000000dd86 R15: ffff88807a943dc0 __netdev_start_xmit include/linux/netdevice.h:4442 [inline] netdev_start_xmit include/linux/netdevice.h:4456 [inline] xmit_one net/core/dev.c:3420 [inline] dev_hard_start_xmit+0x1a3/0x9b0 net/core/dev.c:3436 __dev_queue_xmit+0x2b05/0x35c0 net/core/dev.c:4013 dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 neigh_resolve_output net/core/neighbour.c:1490 [inline] neigh_resolve_output+0x5c4/0x990 net/core/neighbour.c:1470 neigh_output include/net/neighbour.h:511 [inline] ip6_finish_output2+0x109a/0x25c0 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x25e/0x880 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xf1f/0x1490 net/ipv6/ndisc.c:505 ndisc_send_rs+0x134/0x720 net/ipv6/ndisc.c:699 addrconf_rs_timer+0x30f/0x6e0 net/ipv6/addrconf.c:3879 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x4f/0x80 kernel/locking/spinlock.c:199 Code: c0 68 34 13 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d 12 6a 96 01 00 74 20 fb 66 0f 1f 44 00 00 01 00 00 00 e8 e7 ab d3 f9 65 8b 05 18 54 85 78 85 c0 74 06 41 RSP: 0018:ffff88805c6878d8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff122668d RBX: ffff88805d640540 RCX: 0000000000000006 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88805d640dd4 RBP: ffff88805c6878e0 R08: 1ffffffff15377bc R09: fffffbfff15377bd R10: fffffbfff15377bc R11: ffffffff8a9bbde7 R12: ffff88807ec37380 R13: ffff88807ea9c040 R14: ffff888024067580 R15: 0000000000000000 finish_lock_switch kernel/sched/core.c:3124 [inline] finish_task_switch+0x147/0x750 kernel/sched/core.c:3224 context_switch kernel/sched/core.c:3388 [inline] __schedule+0x8e9/0x1f30 kernel/sched/core.c:4081 preempt_schedule_common+0x4f/0xe0 kernel/sched/core.c:4236 preempt_schedule+0x4b/0x60 kernel/sched/core.c:4261 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50 smp_call_function_single+0x410/0x480 kernel/smp.c:313 task_function_call+0xe9/0x180 kernel/events/core.c:114 perf_install_in_context+0x308/0x5a0 kernel/events/core.c:2746 __do_sys_perf_event_open+0x1cbc/0x2c70 kernel/events/core.c:11543 __se_sys_perf_event_open kernel/events/core.c:11151 [inline] __x64_sys_perf_event_open+0xbe/0x150 kernel/events/core.c:11151 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a759 Code: bd b1 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 8b b1 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f759f9d5c88 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 000000000071bfa8 RCX: 000000000045a759 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000180 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 00007f759f9d66d4 R13: 00000000004aec17 R14: 00000000006f1cb0 R15: 00000000ffffffff