======================================
| [  139.988275][    C2]  #3: ffffffff87591d40 (rcu_read_lock){....}-{1:3}, at: ip6_send_skb (./include/linux/rcupdate.h:300 (discriminator 2) ./include/linux/rcupdate.h:840 (discriminator 2) net/ipv6/ip6_output.c:2013 (discriminator 2))
| [  139.988429][    C2]  #4: ffffffff87591d40 (rcu_read_lock){....}-{1:3}, at: ip6_output (./include/linux/rcupdate.h:300 (discriminator 2) ./include/linux/rcupdate.h:840 (discriminator 2) net/ipv6/ip6_output.c:234 (discriminator 2))
| [  139.988607][    C2]
| [  139.988607][    C2] stack backtrace:
[  139.988718][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  139.988720][    C2] Call Trace:
[  139.988721][    C2]  <IRQ>
[  139.988723][    C2]  dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
[  139.988726][    C2]  print_circular_bug.cold (kernel/locking/lockdep.c:2043)
[  139.988729][    C2]  check_noncircular (kernel/locking/lockdep.c:2175)
[  139.988732][    C2]  check_prev_add (kernel/locking/lockdep.c:3165)
[  139.988734][    C2]  validate_chain (kernel/locking/lockdep.c:3284 kernel/locking/lockdep.c:3908)
[  139.988736][    C2]  __lock_acquire (kernel/locking/lockdep.c:5237)
[  139.988739][    C2]  lock_acquire.part.0 (kernel/locking/lockdep.c:5868 (discriminator 1))
[  139.988741][    C2]  ? ___neigh_create (./include/linux/spinlock.h:348 net/core/neighbour.c:670)
[  139.988742][    C2]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  139.988745][    C2]  ? lock_acquire (./include/trace/events/lock.h:23 (discriminator 22) kernel/locking/lockdep.c:5831 (discriminator 22))
[  139.988747][    C2]  _raw_spin_lock_bh (./include/linux/spinlock_api_smp.h:150 (discriminator 1) kernel/locking/spinlock.c:182 (discriminator 1))
[  139.988749][    C2]  ? ___neigh_create (./include/linux/spinlock.h:348 net/core/neighbour.c:670)
[  139.988750][    C2]  ___neigh_create (./include/linux/spinlock.h:348 net/core/neighbour.c:670)
[  139.988752][    C2]  ip6_finish_output2 (net/ipv6/ip6_output.c:128 (discriminator 1))
[  139.988754][    C2]  ? ip6_xmit (net/ipv6/ip6_output.c:328)
[  139.988755][    C2]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[  139.988757][    C2]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5535)
[  139.988759][    C2]  ? ip6_mtu (./include/linux/rcupdate.h:310 (discriminator 2) ./include/linux/rcupdate.h:871 (discriminator 2) ./include/net/ip6_route.h:384 (discriminator 2) net/ipv6/route.c:3290 (discriminator 2))
[  139.988761][    C2]  ip6_finish_output (net/ipv6/ip6_output.c:208 net/ipv6/ip6_output.c:219)
[  139.988763][    C2]  ip6_output (./include/linux/netfilter.h:314 net/ipv6/ip6_output.c:246)
[  139.988765][    C2]  ? ip6_finish_output (./include/linux/skbuff.h:1178)
[  139.988766][    C2]  ? l3mdev_l3_out.constprop.0 (./include/linux/rcupdate.h:873 ./include/net/l3mdev.h:222)
[  139.988770][    C2]  ip6_send_skb (net/ipv6/ip6_output.c:2014)
[  139.988772][    C2]  icmp6_send (net/ipv6/icmp.c:826)
[  139.988774][    C2]  ? icmpv6_push_pending_frames (net/ipv6/icmp.c:291 (discriminator 1))
[  139.988776][    C2]  ? sched_balance_find_src_group (kernel/sched/fair.c:12797)
[  139.988778][    C2]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5535)
[  139.988779][    C2]  ? rcu_read_lock_any_held (./include/linux/lockdep.h:249 kernel/rcu/update.c:386 kernel/rcu/update.c:380)
[  139.988783][    C2]  ? rcu_read_lock_any_held (./include/linux/lockdep.h:249 kernel/rcu/update.c:386 kernel/rcu/update.c:380)
[  139.988786][    C2]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[  139.988787][    C2]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[  139.988789][    C2]  ip6_link_failure (./include/linux/icmpv6.h:24 net/ipv6/route.c:2869)
[  139.988791][    C2]  ndisc_error_report (./include/net/dst.h:438 net/ipv6/ndisc.c:734)
[  139.988793][    C2]  neigh_invalidate (net/core/neighbour.c:1057)
[  139.988794][    C2]  ? neigh_periodic_work (net/core/neighbour.c:973 (discriminator 3))
[  139.988796][    C2]  neigh_timer_handler (net/core/neighbour.c:1149)
[  139.988798][    C2]  ? neigh_periodic_work (net/core/neighbour.c:973 (discriminator 3))
[  139.988799][    C2]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  139.988800][    C2]  call_timer_fn (kernel/time/timer.c:1748)
[  139.988802][    C2]  ? detach_if_pending (./include/linux/list.h:1143)
[  139.988803][    C2]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[  139.988805][    C2]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5535)
[  139.988807][    C2]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  139.988808][    C2]  __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2374)
[  139.988809][    C2]  ? neigh_periodic_work (net/core/neighbour.c:973 (discriminator 3))
[  139.988811][    C2]  ? __bpf_trace_itimer_expire (./include/trace/events/timer.h:407)
[  139.988812][    C2]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[  139.988815][    C2]  ? __rwlock_init (kernel/locking/spinlock_debug.c:48)
[  139.988817][    C2]  run_timer_softirq (kernel/time/timer.c:2386 kernel/time/timer.c:2395 kernel/time/timer.c:2403)
[  139.988818][    C2]  ? clockevents_program_event (kernel/time/clockevents.c:372)
[  139.988822][    C2]  ? __run_timers (./include/trace/events/timer.h:138 (discriminator 19))
[  139.988823][    C2]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 22))
[  139.988825][    C2]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  139.988827][    C2]  handle_softirqs (kernel/softirq.c:622)
[  139.988829][    C2]  ? _local_bh_enable (kernel/softirq.c:405 (discriminator 1))
[  139.988831][    C2]  __irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)
[  139.988833][    C2]  irq_exit_rcu (kernel/softirq.c:752)
[  139.988835][    C2]  sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1062 (discriminator 37) arch/x86/kernel/apic/apic.c:1062 (discriminator 37))
[  139.988836][    C2]  </IRQ>
[  139.988837][    C2]  <TASK>
[  139.988837][    C2]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[  139.988839][    C2]  asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:674)
[  139.988840][    C2] RIP: 0010:pv_native_safe_halt (./arch/x86/include/asm/irqflags.h:48 arch/x86/kernel/paravirt.c:63)
[  139.988843][    C2] Code: 48 8b 3d 44 61 6e 02 e8 1f 00 00 00 48 2b 05 08 22 a7 00 c3 0f 1f 80 00 00 00 00 f3 0f 1e fa eb 07 0f 00 2d a3 dd 19 00 fb f4 <c3> 0f 1f 40 d6 48 83 ec 20 8b 17 49 89 f8 83 e2 fe 41 89 d2 0f 01
All code
========
   0:	48 8b 3d 44 61 6e 02 	mov    0x26e6144(%rip),%rdi        # 0x26e614b
   7:	e8 1f 00 00 00       	call   0x2b
   c:	48 2b 05 08 22 a7 00 	sub    0xa72208(%rip),%rax        # 0xa7221b
  13:	c3                   	ret
  14:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  1b:	f3 0f 1e fa          	endbr64
  1f:	eb 07                	jmp    0x28
  21:	0f 00 2d a3 dd 19 00 	verw   0x19dda3(%rip)        # 0x19ddcb
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	c3                   	ret		<-- trapping instruction
  2b:	0f 1f 40 d6          	nopl   -0x2a(%rax)
  2f:	48 83 ec 20          	sub    $0x20,%rsp
  33:	8b 17                	mov    (%rdi),%edx
  35:	49 89 f8             	mov    %rdi,%r8
  38:	83 e2 fe             	and    $0xfffffffe,%edx
  3b:	41 89 d2             	mov    %edx,%r10d
  3e:	0f                   	.byte 0xf
  3f:	01                   	.byte 0x1

Code starting with the faulting instruction
===========================================
   0:	c3                   	ret
   1:	0f 1f 40 d6          	nopl   -0x2a(%rax)
   5:	48 83 ec 20          	sub    $0x20,%rsp
   9:	8b 17                	mov    (%rdi),%edx
   b:	49 89 f8             	mov    %rdi,%r8
   e:	83 e2 fe             	and    $0xfffffffe,%edx
  11:	41 89 d2             	mov    %edx,%r10d
  14:	0f                   	.byte 0xf
  15:	01                   	.byte 0x1
[  139.988844][    C2] RSP: 0018:ffa0000000157e00 EFLAGS: 00000282
[  139.988846][    C2] RAX: 000000000066cc85 RBX: ff11000001bac6c0 RCX: ffffffff838f7f27
[  139.988848][    C2] RDX: ff11000001bac6c0 RSI: ffffffff86ac4933 RDI: ffffffff8647d760
[  139.988848][    C2] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[  139.988849][    C2] R10: 0000000000000002 R11: 0000000000000001 R12: 1ff400000002afc3
[  139.988850][    C2] R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
[  139.988852][    C2]  ? cpuidle_idle_call.constprop.0 (kernel/sched/idle.c:199)
[  139.988854][    C2]  default_idle (./arch/x86/include/asm/paravirt.h:62 arch/x86/kernel/process.c:768)
[  139.988856][    C2]  default_idle_call (kernel/sched/idle.c:122)
[  139.988857][    C2]  cpuidle_idle_call.constprop.0 (kernel/sched/idle.c:199)
[  139.988859][    C2]  ? arch_cpu_idle_exit+0x40/0x40
[  139.988861][    C2]  ? mark_tsc_async_resets (arch/x86/kernel/tsc_sync.c:49)
[  139.988862][    C2]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 22))
[  139.988864][    C2]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  139.988865][    C2]  do_idle (kernel/sched/idle.c:355)
[  139.988867][    C2]  cpu_startup_entry (kernel/sched/idle.c:454)
[  139.988869][    C2]  start_secondary (arch/x86/kernel/smpboot.c:312)
[  139.988871][    C2]  ? set_cpu_sibling_map (arch/x86/kernel/smpboot.c:733 (discriminator 4))


Finger prints:
check_prev_add:validate_chain:__lock_acquire:_raw_spin_lock_bh:___neigh_create