======================================
| [   22.037028][    C1] 1 lock held by kworker/1:1/69:
| [ 22.037217][ C1] #0: ffffc900001e0ae8 ((&n->timer)){+.-.}-{0:0}, at: call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
| [   22.037575][    C1]
| [   22.037575][    C1] stack backtrace:
[   22.037803][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   22.037806][    C1] Workqueue:  0x0 (events)
[   22.037813][    C1] Call Trace:
[   22.037815][    C1]  <IRQ>
[ 22.037818][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 22.037828][ C1] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) 
[ 22.037838][ C1] icmp6_send (./include/net/net_namespace.h:404 ./include/linux/netdevice.h:2669 net/ipv6/icmp.c:476) 
[ 22.037859][ C1] ? __pfx_icmp6_send (net/ipv6/icmp.c:452) 
[ 22.037867][ C1] ? __pfx_validate_chain (kernel/locking/lockdep.c:3862) 
[ 22.037872][ C1] ? 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) 
[ 22.037876][ C1] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 22.037885][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 22.037892][ C1] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 22.037898][ C1] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 22.037901][ C1] ? neigh_invalidate (net/core/neighbour.c:1008) 
[ 22.037907][ C1] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 22.037910][ C1] ? lock_acquire.part.0 (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853) 
[ 22.037921][ C1] ip6_link_failure (./include/linux/skbuff.h:1152 net/ipv6/route.c:2801) 
[ 22.037930][ C1] ndisc_error_report (./include/net/dst.h:429 net/ipv6/ndisc.c:731) 
[ 22.037937][ C1] neigh_invalidate (net/core/neighbour.c:1008) 
[ 22.037946][ C1] neigh_timer_handler (net/core/neighbour.c:1109 (discriminator 2)) 
[ 22.037956][ C1] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 22.037959][ C1] call_timer_fn (kernel/time/timer.c:1789) 
[ 22.037962][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 22.037965][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 22.037968][ C1] ? __pfx_call_timer_fn (kernel/time/timer.c:1766) 
[ 22.037971][ C1] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 22.037989][ C1] __run_timers (kernel/time/timer.c:1841 kernel/time/timer.c:2414) 
[ 22.037992][ C1] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 22.038002][ C1] ? __pfx___run_timers (kernel/time/timer.c:2385) 
[ 22.038005][ C1] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 22.038012][ C1] ? 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) 
[ 22.038018][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 22.038023][ C1] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 22.038025][ C1] ? timer_expire_remote (kernel/time/timer.c:2426 kernel/time/timer.c:2418 kernel/time/timer.c:2177) 
[ 22.038035][ C1] timer_expire_remote (kernel/time/timer.c:2427 kernel/time/timer.c:2418 kernel/time/timer.c:2177) 
[ 22.038039][ C1] tmigr_handle_remote_cpu (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:87 ./arch/x86/include/asm/irqflags.h:147 kernel/time/timer_migration.c:961) 
[ 22.038047][ C1] ? __pfx_tmigr_handle_remote_cpu (kernel/time/timer_migration.c:905) 
[ 22.038050][ C1] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 22.038053][ C1] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 22.038071][ C1] tmigr_handle_remote_up (kernel/time/timer_migration.c:1038) 
[ 22.038077][ C1] ? __pfx_tmigr_handle_remote_up (kernel/time/timer_migration.c:1005) 
[ 22.038082][ C1] __walk_groups.isra.0 (kernel/time/timer_migration.c:533) 
[ 22.038092][ C1] tmigr_handle_remote (kernel/time/timer_migration.c:1096) 
[ 22.038097][ C1] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1059) 
[ 22.038099][ C1] ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:94 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86) 
[ 22.038105][ C1] ? ktime_get (kernel/time/timekeeping.c:226 (discriminator 4) kernel/time/timekeeping.c:335 (discriminator 4) kernel/time/timekeeping.c:752 (discriminator 4)) 
[ 22.038112][ C1] ? clockevents_program_event (kernel/time/clockevents.c:334 (discriminator 3)) 
[ 22.038125][ C1] handle_softirqs (kernel/softirq.c:561) 
[ 22.038133][ C1] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 22.038141][ C1] __irq_exit_rcu (kernel/softirq.c:596 kernel/softirq.c:435 kernel/softirq.c:662) 
[ 22.038144][ C1] irq_exit_rcu (kernel/softirq.c:680) 
[ 22.038147][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   22.038152][    C1]  </IRQ>
[   22.038153][    C1]  <TASK>
[ 22.038155][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 22.038161][ C1] RIP: 0010:_raw_spin_unlock_irq (./include/linux/spinlock_api_smp.h:160 kernel/locking/spinlock.c:202) 
[ 22.038164][ C1] Code: 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 e5 74 88 fd 48 89 ef e8 2d e5 88 fd e8 18 04 ae fd fb 65 ff 0d e8 7d 90 59 <74> 06 5d c3 cc cc cc cc 0f 1f 44 00 00 5d c3 cc cc cc cc 66 66 2e
All code
========
   0:	44 00 00             	add    %r8b,(%rax)
   3:	55                   	push   %rbp
   4:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
   9:	48 89 fd             	mov    %rdi,%rbp
   c:	48 83 c7 18          	add    $0x18,%rdi
  10:	e8 e5 74 88 fd       	call   0xfffffffffd8874fa
  15:	48 89 ef             	mov    %rbp,%rdi
  18:	e8 2d e5 88 fd       	call   0xfffffffffd88e54a
  1d:	e8 18 04 ae fd       	call   0xfffffffffdae043a
  22:	fb                   	sti
  23:	65 ff 0d e8 7d 90 59 	decl   %gs:0x59907de8(%rip)        # 0x59907e12
  2a:*	74 06                	je     0x32		<-- trapping instruction
  2c:	5d                   	pop    %rbp
  2d:	c3                   	ret
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  37:	5d                   	pop    %rbp
  38:	c3                   	ret
  39:	cc                   	int3
  3a:	cc                   	int3
  3b:	cc                   	int3
  3c:	cc                   	int3
  3d:	66                   	data16
  3e:	66                   	data16
  3f:	2e                   	cs

Code starting with the faulting instruction
===========================================
   0:	74 06                	je     0x8
   2:	5d                   	pop    %rbp
   3:	c3                   	ret
   4:	cc                   	int3
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
   d:	5d                   	pop    %rbp
   e:	c3                   	ret
   f:	cc                   	int3
  10:	cc                   	int3
  11:	cc                   	int3
  12:	cc                   	int3
  13:	66                   	data16
  14:	66                   	data16
  15:	2e                   	cs
[   22.038167][    C1] RSP: 0000:ffffc900004a7dd8 EFLAGS: 00000286
[   22.038170][    C1] RAX: 00000000001ed009 RBX: ffff88800868c5c0 RCX: 1ffffffff5031991
[   22.038172][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa67346d8
[   22.038174][    C1] RBP: ffff8880360bc6c0 R08: 0000000000000001 R09: 0000000000000001
[   22.038175][    C1] R10: ffffffffa8191197 R11: ffff88800868c5c0 R12: ffffed1001266f40
[   22.038177][    C1] R13: ffff8880093379c0 R14: ffff8880360bc6c0 R15: ffffed1006c178e4
[ 22.038188][ C1] ? _raw_spin_unlock_irq (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./include/linux/spinlock_api_smp.h:159 kernel/locking/spinlock.c:202) 
[ 22.038194][ C1] ? _raw_spin_unlock_irq (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./include/linux/spinlock_api_smp.h:159 kernel/locking/spinlock.c:202) 
[ 22.038197][ C1] ? worker_thread (kernel/workqueue.c:3411) 
[ 22.038200][ C1] worker_thread (kernel/workqueue.c:3413) 
[ 22.038204][ C1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4349 kernel/locking/lockdep.c:4408) 
[ 22.038215][ C1] ? __pfx_worker_thread (kernel/workqueue.c:3344) 
[ 22.038220][ C1] kthread (kernel/kthread.c:464) 
[ 22.038226][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 22.038236][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 22.038242][ C1] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 22.038248][ C1] ? __pfx_kthread (kernel/kthread.c:413) 


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