======================================
| [ 13.791573][ C3] #4: ffff88800d593358 (&br->multicast_lock){+.-.}-{3:3}, at: br_multicast_port_query_expired (./include/trace/events/../../../net/bridge/br_private.h:1293 ./include/trace/events/../../../net/bridge/br_private.h:1302 net/bridge/br_multicast.c:1906) bridge 
| [ 13.792184][ C3] #5: ffffffff85f5b5c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit (./include/linux/bottom_half.h:20 ./include/linux/rcupdate.h:901 net/core/dev.c:4555) 
| [   13.792662][    C3]
| [   13.792662][    C3] stack backtrace:
[   13.792928][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.792931][    C3] Workqueue: events_unbound linkwatch_event
[   13.792937][    C3] Call Trace:
[   13.792939][    C3]  <IRQ>
[ 13.792942][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.792949][ C3] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) 
[ 13.792961][ C3] dev_hard_start_xmit (./include/net/net_namespace.h:418 ./include/linux/netdevice.h:2695 net/core/dev.c:2466 net/core/dev.c:3772 net/core/dev.c:3793) 
[ 13.792972][ C3] __dev_queue_xmit (net/core/dev.h:340 net/core/dev.c:4631) 
[ 13.792988][ C3] ? __build_skb_around (./arch/x86/include/asm/atomic.h:28 ./include/linux/atomic/atomic-arch-fallback.h:503 ./include/linux/atomic/atomic-instrumented.h:68 net/core/skbuff.c:381 net/core/skbuff.c:439) 
[ 13.793003][ C3] ? __pfx___dev_queue_xmit (net/core/dev.c:4538) 
[ 13.793007][ C3] ? __pfx___alloc_skb (net/core/skbuff.c:642) 
[ 13.793016][ C3] ? stack_trace_save (kernel/stacktrace.c:114) 
[ 13.793025][ C3] ? __pfx_stack_trace_save (kernel/stacktrace.c:114) 
[ 13.793037][ C3] ? __pfx___br_multicast_query_handle_vlan (net/bridge/br_multicast.c:909) bridge 
[ 13.793134][ C3] br_dev_queue_push_xmit (net/bridge/br_forward.c:34) bridge 
[ 13.793191][ C3] ? __pfx_br_dev_queue_push_xmit (net/bridge/br_forward.c:34) bridge 
[ 13.793250][ C3] ? br_multicast_count (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 ./include/trace/events/../../../net/bridge/br_private.h:764 net/bridge/br_multicast.c:5052) bridge 
[ 13.793291][ C3] __br_multicast_send_query (net/bridge/br_multicast.c:1813) bridge 
[ 13.793336][ C3] ? __pfx___br_multicast_send_query (net/bridge/br_multicast.c:1789) bridge 
[ 13.793376][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 13.793389][ C3] ? br_multicast_send_query (net/bridge/br_multicast.c:1891) bridge 
[ 13.793423][ C3] br_multicast_send_query (net/bridge/br_multicast.c:1891) bridge 
[ 13.793461][ C3] ? __pfx_br_multicast_send_query (net/bridge/br_multicast.c:1852) bridge 
[ 13.793494][ C3] ? br_multicast_port_query_expired (./include/trace/events/../../../net/bridge/br_private.h:1293 ./include/trace/events/../../../net/bridge/br_private.h:1302 net/bridge/br_multicast.c:1906) bridge 
[ 13.793531][ C3] ? __pfx_br_ip4_multicast_port_query_expired (net/bridge/br_multicast.c:1920) bridge 
[ 13.793566][ C3] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 13.793572][ C3] ? 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) 
[ 13.793577][ C3] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 13.793581][ C3] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 13.793583][ C3] ? br_multicast_port_query_expired (./include/trace/events/../../../net/bridge/br_private.h:1293 ./include/trace/events/../../../net/bridge/br_private.h:1302 net/bridge/br_multicast.c:1906) bridge 
[ 13.793624][ C3] ? br_multicast_port_query_expired (net/bridge/br_multicast.c:1917) bridge 
[ 13.793657][ C3] br_multicast_port_query_expired (net/bridge/br_multicast.c:1917) bridge 
[ 13.793693][ C3] ? __pfx_br_ip4_multicast_port_query_expired (net/bridge/br_multicast.c:1920) bridge 
[ 13.793727][ C3] call_timer_fn (kernel/time/timer.c:1789) 
[ 13.793732][ C3] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 13.793735][ C3] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 13.793739][ C3] ? __pfx_call_timer_fn (kernel/time/timer.c:1766) 
[ 13.793743][ C3] ? 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) 
[ 13.793752][ C3] ? mark_held_locks (kernel/locking/lockdep.c:4323) 
[ 13.793764][ C3] __run_timers (kernel/time/timer.c:1841 kernel/time/timer.c:2414) 
[ 13.793768][ C3] ? __pfx_br_ip4_multicast_port_query_expired (net/bridge/br_multicast.c:1920) bridge 
[ 13.793810][ C3] ? __pfx___run_timers (kernel/time/timer.c:2385) 
[ 13.793813][ C3] ? clockevents_program_event (kernel/time/clockevents.c:326) 
[ 13.793822][ C3] ? 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) 
[ 13.793827][ C3] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 13.793830][ C3] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 13.793833][ C3] ? run_timer_softirq (kernel/time/timer.c:2426 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 13.793844][ C3] run_timer_softirq (kernel/time/timer.c:2427 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 13.793849][ C3] handle_softirqs (kernel/softirq.c:561) 
[ 13.793862][ C3] __irq_exit_rcu (kernel/softirq.c:596 kernel/softirq.c:435 kernel/softirq.c:662) 
[ 13.793866][ C3] irq_exit_rcu (kernel/softirq.c:680) 
[ 13.793869][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   13.793873][    C3]  </IRQ>
[   13.793874][    C3]  <TASK>
[ 13.793877][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.793882][ C3] RIP: 0010:_raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.793886][ C3] Code: 10 e8 b1 3d 87 fd 48 89 ef e8 f9 ad 87 fd 81 e3 00 02 00 00 75 1d 9c 58 f6 c4 02 75 29 48 85 db 74 01 fb 65 ff 0d b5 0d 0f 7b <74> 0e 5b 5d c3 cc cc cc cc e8 2f df ac fd eb dc 0f 1f 44 00 00 5b
All code
========
   0:	10 e8                	adc    %ch,%al
   2:	b1 3d                	mov    $0x3d,%cl
   4:	87 fd                	xchg   %edi,%ebp
   6:	48 89 ef             	mov    %rbp,%rdi
   9:	e8 f9 ad 87 fd       	call   0xfffffffffd87ae07
   e:	81 e3 00 02 00 00    	and    $0x200,%ebx
  14:	75 1d                	jne    0x33
  16:	9c                   	pushf
  17:	58                   	pop    %rax
  18:	f6 c4 02             	test   $0x2,%ah
  1b:	75 29                	jne    0x46
  1d:	48 85 db             	test   %rbx,%rbx
  20:	74 01                	je     0x23
  22:	fb                   	sti
  23:	65 ff 0d b5 0d 0f 7b 	decl   %gs:0x7b0f0db5(%rip)        # 0x7b0f0ddf
  2a:*	74 0e                	je     0x3a		<-- trapping instruction
  2c:	5b                   	pop    %rbx
  2d:	5d                   	pop    %rbp
  2e:	c3                   	ret
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	e8 2f df ac fd       	call   0xfffffffffdacdf67
  38:	eb dc                	jmp    0x16
  3a:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  3f:	5b                   	pop    %rbx

Code starting with the faulting instruction
===========================================
   0:	74 0e                	je     0x10
   2:	5b                   	pop    %rbx
   3:	5d                   	pop    %rbp
   4:	c3                   	ret
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	cc                   	int3
   9:	e8 2f df ac fd       	call   0xfffffffffdacdf3d
   e:	eb dc                	jmp    0xffffffffffffffec
  10:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  15:	5b                   	pop    %rbx
[   13.793888][    C3] RSP: 0018:ffffc9000031f180 EFLAGS: 00000282
[   13.793892][    C3] RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff10066b1
[   13.793894][    C3] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84f4b761
[   13.793895][    C3] RBP: ffff88800104f440 R08: 0000000000000001 R09: fffffbfff1005be1
[   13.793897][    C3] R10: ffffffff8802df0f R11: ffff8880021645c0 R12: ffff88800104f440
[   13.793899][    C3] R13: ffffea000029e080 R14: ffff88800104de40 R15: ffff88800a782278
[ 13.793911][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.793920][ C3] get_partial_node.part.0 (mm/slub.c:2870) 
[ 13.793934][ C3] ? __alloc_object (mm/kmemleak.c:471 mm/kmemleak.c:651) 
[ 13.793939][ C3] ___slab_alloc (mm/slub.c:2831 mm/slub.c:2948 mm/slub.c:3806) 
[ 13.793944][ C3] ? __alloc_object (mm/kmemleak.c:471 mm/kmemleak.c:651) 
[ 13.793948][ C3] ? ref_tracker_alloc (lib/ref_tracker.c:195) 
[ 13.793953][ C3] ? get_any_partial (./include/linux/seqlock.h:72 ./include/linux/cpuset.h:144 mm/slub.c:2909) 
[ 13.793959][ C3] ? addrconf_add_linklocal (./include/linux/spinlock.h:356 net/ipv6/addrconf.c:4164 net/ipv6/addrconf.c:3309) 
[ 13.793963][ C3] ? addrconf_addr_gen (net/ipv6/addrconf.c:3436) 
[ 13.793966][ C3] ? addrconf_notify (./include/linux/err.h:81 net/ipv6/addrconf.c:3741) 
[ 13.793969][ C3] ? notifier_call_chain (kernel/notifier.c:85 (discriminator 2)) 
[ 13.793974][ C3] ? netdev_state_change (net/core/dev.c:1538 net/core/dev.c:1529) 
[ 13.793976][ C3] ? linkwatch_do_dev (net/core/link_watch.c:186) 
[ 13.793979][ C3] ? __linkwatch_run_queue (./include/linux/spinlock.h:376 net/core/link_watch.c:245) 
[ 13.793982][ C3] ? linkwatch_event (net/core/link_watch.c:287) 
[ 13.793984][ C3] ? process_one_work (kernel/workqueue.c:3238) 
[ 13.793992][ C3] ? __alloc_object (mm/kmemleak.c:471 mm/kmemleak.c:651) 
[ 13.793996][ C3] ? kmem_cache_alloc_noprof (mm/slub.c:3916 mm/slub.c:3991 mm/slub.c:4152 mm/slub.c:4171) 
[ 13.793999][ C3] kmem_cache_alloc_noprof (mm/slub.c:3916 mm/slub.c:3991 mm/slub.c:4152 mm/slub.c:4171) 
[ 13.794005][ C3] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 13.794012][ C3] __alloc_object (mm/kmemleak.c:471 mm/kmemleak.c:651) 
[ 13.794021][ C3] __create_object (mm/kmemleak.c:760) 
[ 13.794033][ C3] __kmalloc_cache_noprof (./include/linux/kmemleak.h:43 mm/slub.c:4119 mm/slub.c:4164 mm/slub.c:4320) 
[ 13.794054][ C3] ref_tracker_alloc (lib/ref_tracker.c:203) 
[ 13.794064][ C3] ? __pfx_ref_tracker_alloc (lib/ref_tracker.c:188) 
[ 13.794068][ C3] ? dev_get_by_index (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/dev.c:982) 
[ 13.794076][ C3] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 13.794082][ C3] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 13.794105][ C3] ? dev_get_by_index (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/dev.c:982) 
[ 13.794126][ C3] netdev_get_by_index (net/core/dev.c:1008) 
[ 13.794137][ C3] fib6_nh_init (net/ipv6/route.c:3554) 
[ 13.794146][ C3] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4349 kernel/locking/lockdep.c:4408) 
[ 13.794160][ C3] ? __pfx_fib6_nh_init (net/ipv6/route.c:3535) 
[ 13.794171][ C3] ? trace_kmalloc (./include/trace/events/kmem.h:54 (discriminator 21)) 
[ 13.794176][ C3] ? __kmalloc_noprof (mm/slub.c:4307) 
[ 13.794196][ C3] ip6_route_info_create (net/ipv6/route.c:3824) 
[ 13.794216][ C3] ? __pfx_ip6_route_info_create (net/ipv6/route.c:3705) 
[ 13.794226][ C3] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 13.794246][ C3] ip6_route_add (net/ipv6/route.c:3867) 
[ 13.794259][ C3] addrconf_prefix_route (net/ipv6/addrconf.c:2461) 
[ 13.794276][ C3] ? __pfx_addrconf_prefix_route (net/ipv6/addrconf.c:2461) 
[ 13.794281][ C3] ? atomic_notifier_call_chain (kernel/notifier.c:227) 
[ 13.794332][ C3] ? ip6_route_add (net/ipv6/route.c:3875) 
[ 13.794350][ C3] addrconf_add_linklocal (./include/linux/spinlock.h:356 net/ipv6/addrconf.c:4164 net/ipv6/addrconf.c:3309) 
[ 13.794361][ C3] ? __pfx_addrconf_add_linklocal (net/ipv6/addrconf.c:3286) 
[ 13.794396][ C3] addrconf_addr_gen (net/ipv6/addrconf.c:3436) 
[ 13.794404][ C3] ? __pfx_addrconf_addr_gen (net/ipv6/addrconf.c:3405) 
[ 13.794429][ C3] ? addrconf_notify (./include/linux/err.h:81 net/ipv6/addrconf.c:3741) 
[ 13.794435][ C3] addrconf_notify (./include/linux/err.h:81 net/ipv6/addrconf.c:3741) 
[ 13.794449][ C3] notifier_call_chain (kernel/notifier.c:85 (discriminator 2)) 
[ 13.794469][ C3] netdev_state_change (net/core/dev.c:1538 net/core/dev.c:1529) 
[ 13.794477][ C3] ? __pfx_netdev_state_change (net/core/dev.c:1530) 
[ 13.794507][ C3] linkwatch_do_dev (net/core/link_watch.c:186) 
[ 13.794516][ C3] __linkwatch_run_queue (./include/linux/spinlock.h:376 net/core/link_watch.c:245) 
[ 13.794529][ C3] ? __pfx___linkwatch_run_queue (net/core/link_watch.c:195) 
[ 13.794542][ C3] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 13.794561][ C3] linkwatch_event (net/core/link_watch.c:287) 
[ 13.794565][ C3] process_one_work (kernel/workqueue.c:3238) 
[ 13.794592][ C3] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 13.794602][ C3] ? __pfx_process_one_work (kernel/workqueue.c:3140) 
[ 13.794627][ C3] ? assign_work (kernel/workqueue.c:1200) 
[ 13.794646][ C3] worker_thread (kernel/workqueue.c:3313 kernel/workqueue.c:3400) 
[ 13.794673][ C3] ? __pfx_worker_thread (kernel/workqueue.c:3346) 
[ 13.794686][ C3] kthread (kernel/kthread.c:464) 
[ 13.794694][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 13.794711][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 13.794723][ C3] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 13.794729][ C3] ? __pfx_kthread (kernel/kthread.c:413) 


Finger prints:
lockdep_rcu_suspicious:dev_hard_start_xmit:__dev_queue_xmit:br_dev_queue_push_xmit:__br_multicast_send_query