======================================
| [  161.725766][    C2] 1 lock held by swapper/2/0:
| [ 161.725970][ C2] #0: ffffc90000238d60 ((&n->timer)){+.-.}-{0:0}, at: call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
| [  161.726361][    C2]
| [  161.726361][    C2] stack backtrace:
[  161.726605][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  161.726607][    C2] Call Trace:
[  161.726609][    C2]  <IRQ>
[ 161.726612][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 161.726622][ C2] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) 
[ 161.726632][ C2] icmp6_send (./include/net/net_namespace.h:404 ./include/linux/netdevice.h:2669 net/ipv6/icmp.c:476) 
[ 161.726642][ C2] ? is_bpf_text_address (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 kernel/bpf/core.c:774) 
[ 161.726659][ C2] ? __pfx_icmp6_send (net/ipv6/icmp.c:452) 
[ 161.726668][ C2] ? __pfx_validate_chain (kernel/locking/lockdep.c:3862) 
[ 161.726672][ C2] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 161.726675][ C2] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 161.726685][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 161.726691][ C2] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 161.726698][ C2] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 161.726700][ C2] ? neigh_invalidate (net/core/neighbour.c:1008) 
[ 161.726706][ C2] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 161.726710][ C2] ? lock_acquire.part.0 (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853) 
[ 161.726721][ C2] ip6_link_failure (./include/linux/skbuff.h:1152 net/ipv6/route.c:2801) 
[ 161.726729][ C2] ndisc_error_report (./include/net/dst.h:429 net/ipv6/ndisc.c:731) 
[ 161.726737][ C2] neigh_invalidate (net/core/neighbour.c:1008) 
[ 161.726746][ C2] neigh_timer_handler (net/core/neighbour.c:1109 (discriminator 2)) 
[ 161.726756][ C2] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 161.726759][ C2] call_timer_fn (kernel/time/timer.c:1789) 
[ 161.726762][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 161.726765][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 161.726768][ C2] ? __pfx_call_timer_fn (kernel/time/timer.c:1766) 
[ 161.726771][ C2] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 161.726789][ C2] __run_timers (kernel/time/timer.c:1841 kernel/time/timer.c:2414) 
[ 161.726792][ C2] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 161.726803][ C2] ? __pfx___run_timers (kernel/time/timer.c:2385) 
[ 161.726806][ C2] ? clockevents_program_event (kernel/time/clockevents.c:326) 
[ 161.726816][ C2] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:107 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 161.726823][ C2] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 161.726827][ C2] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 161.726830][ C2] ? run_timer_softirq (kernel/time/timer.c:2426 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 161.726840][ C2] run_timer_softirq (kernel/time/timer.c:2427 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 161.726845][ C2] handle_softirqs (kernel/softirq.c:561) 
[ 161.726859][ C2] __irq_exit_rcu (kernel/softirq.c:596 kernel/softirq.c:435 kernel/softirq.c:662) 
[ 161.726862][ C2] irq_exit_rcu (kernel/softirq.c:680) 
[ 161.726865][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[  161.726870][    C2]  </IRQ>
[  161.726871][    C2]  <TASK>
[ 161.726873][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 161.726880][ C2] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:92 arch/x86/kernel/process.c:744) 
[ 161.726884][ C2] Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 cc 14 00 fb f4 <fa> c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
All code
========
   0:	4c 01 c7             	add    %r8,%rdi
   3:	4c 29 c2             	sub    %r8,%rdx
   6:	e9 72 ff ff ff       	jmp    0xffffffffffffff7d
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d 23 cc 14 00 	verw   0x14cc23(%rip)        # 0x14cc4b
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	fa                   	cli		<-- trapping instruction
  2b:	c3                   	ret
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  37:	00 00 00 00 
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	fa                   	cli
   1:	c3                   	ret
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   5:	cc                   	int3
   6:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
   d:	00 00 00 00 
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[  161.726888][    C2] RSP: 0018:ffffc90000167df8 EFLAGS: 00000246
[  161.726891][    C2] RAX: 00000000002377b1 RBX: 1ffff9200002cfc1 RCX: ffffffff96914b15
[  161.726894][    C2] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff94169634
[  161.726895][    C2] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c2703a
[  161.726897][    C2] R10: ffff8880361381d3 R11: ffff888001b38040 R12: 0000000000000000
[  161.726898][    C2] R13: ffff888001b38040 R14: dffffc0000000000 R15: 0000000000000000
[ 161.726908][ C2] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 161.726912][ C2] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 161.726921][ C2] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 161.726924][ C2] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 161.726929][ C2] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 161.726936][ C2] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 161.726946][ C2] do_idle (kernel/sched/idle.c:325) 
[ 161.726953][ C2] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 161.726957][ C2] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 161.726961][ C2] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 


Finger prints:
lockdep_rcu_suspicious:icmp6_send:ip6_link_failure:ndisc_error_report:neigh_invalidate