======================================
| [ 3827.389982][   T76] br0: port 2(geneve_a) entered disabled state
| [ 3827.391468][   T76] veth_A-C: left allmulticast mode
| [ 3827.391622][   T76] veth_A-C: left promiscuous mode
| [ 3827.391901][   T76] br0: port 1(veth_A-C) entered disabled state
| [ 4559.216197][T31091] unregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 5
[ 4559.216736][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 2/4 users at
[4559.216736][T31091] dst_init (net/core/dst.c:53) 
[4559.216736][T31091] dst_alloc (net/core/dst.c:96) 
[4559.216736][T31091] ip6_dst_alloc (net/ipv6/route.c:344) 
[4559.216736][T31091] ip6_rt_pcpu_alloc (net/ipv6/route.c:1381) 
[4559.216736][T31091] ip6_pol_route (net/ipv6/route.c:1429 net/ipv6/route.c:2266) 
[4559.216736][T31091] fib6_rule_lookup (./include/net/ip6_fib.h:616 net/ipv6/fib6_rules.c:121) 
[4559.216736][T31091] ip6_route_output_flags (net/ipv6/route.c:2638 net/ipv6/route.c:2650) 
[4559.216736][T31091] ip6_dst_lookup_tail.constprop.0 (net/ipv6/ip6_output.c:1147) 
[4559.216736][T31091] ip6_dst_lookup_flow (net/ipv6/ip6_output.c:1251) 
[4559.216736][T31091] udp_tunnel6_dst_lookup (net/ipv6/ip6_udp_tunnel.c:165 net/ipv6/ip6_udp_tunnel.c:135) 
[4559.216736][T31091] vxlan_xmit_one (drivers/net/vxlan/vxlan_core.c:2538 (discriminator 4)) vxlan
[4559.216736][T31091] vxlan_xmit (drivers/net/vxlan/vxlan_core.c:2803) vxlan
[4559.216736][T31091] dev_hard_start_xmit (./include/linux/netdevice.h:4894 ./include/linux/netdevice.h:4908 net/core/dev.c:3580 net/core/dev.c:3596) 
[4559.216736][T31091] __dev_queue_xmit (net/core/dev.h:185 net/core/dev.c:4404) 
[4559.216736][T31091] ip6_finish_output2 (./include/net/neighbour.h:540 net/ipv6/ip6_output.c:137) 
[4559.216736][T31091] ip6_finish_output (net/ipv6/ip6_output.c:211 net/ipv6/ip6_output.c:222) 
| [4559.216736][T31091] dev_hard_start_xmit (./include/linux/netdevice.h:4894 ./include/linux/netdevice.h:4908 net/core/dev.c:3580 net/core/dev.c:3596) 
| [4559.216736][T31091] __dev_queue_xmit (net/core/dev.h:185 net/core/dev.c:4404) 
| [4559.216736][T31091] ip6_finish_output2 (./include/net/neighbour.h:540 net/ipv6/ip6_output.c:137) 
| [4559.216736][T31091] ip6_finish_output (net/ipv6/ip6_output.c:211 net/ipv6/ip6_output.c:222) 
| [ 4559.216736][T31091]
[ 4559.219782][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 1/4 users at
[4559.219782][T31091] netdev_get_by_index (net/core/dev.c:916) 
[4559.219782][T31091] fib6_nh_init (net/ipv6/route.c:3542) 
[4559.219782][T31091] nh_create_ipv6 (net/ipv4/nexthop.c:2827) 
[4559.219782][T31091] nexthop_create (net/ipv4/nexthop.c:2878) 
[4559.219782][T31091] rtm_new_nexthop (net/ipv4/nexthop.c:2920 net/ipv4/nexthop.c:3206) 
[4559.219782][T31091] rtnetlink_rcv_msg (net/core/rtnetlink.c:6598) 
[4559.219782][T31091] netlink_rcv_skb (net/netlink/af_netlink.c:2564) 
[4559.219782][T31091] netlink_unicast (net/netlink/af_netlink.c:1335 net/netlink/af_netlink.c:1361) 
[4559.219782][T31091] netlink_sendmsg (net/netlink/af_netlink.c:1905) 
[4559.219782][T31091] ____sys_sendmsg (net/socket.c:730 net/socket.c:745 net/socket.c:2585) 
[4559.219782][T31091] ___sys_sendmsg (net/socket.c:2641) 
[4559.219782][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
[4559.219782][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[4559.219782][T31091] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
| [4559.219782][T31091] ___sys_sendmsg (net/socket.c:2641) 
| [4559.219782][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
| [4559.219782][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
| [4559.219782][T31091] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
| [ 4559.219782][T31091]
[ 4559.221734][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 1/4 users at
[4559.221734][T31091] ipv6_add_dev (net/ipv6/addrconf.c:344 net/ipv6/addrconf.c:409) 
[4559.221734][T31091] addrconf_notify (net/ipv6/addrconf.c:3653) 
[4559.221734][T31091] notifier_call_chain (kernel/notifier.c:93 (discriminator 2)) 
[4559.221734][T31091] register_netdevice (./include/linux/notifier.h:207 net/core/dev.c:10436) 
[4559.221734][T31091] veth_newlink (drivers/net/veth.c:1860) 
[4559.221734][T31091] rtnl_newlink_create (net/core/rtnetlink.c:3513) 
[4559.221734][T31091] __rtnl_newlink (net/core/rtnetlink.c:3733) 
[4559.221734][T31091] rtnl_newlink (net/core/rtnetlink.c:3747) 
[4559.221734][T31091] rtnetlink_rcv_msg (net/core/rtnetlink.c:6598) 
[4559.221734][T31091] netlink_rcv_skb (net/netlink/af_netlink.c:2564) 
[4559.221734][T31091] netlink_unicast (net/netlink/af_netlink.c:1335 net/netlink/af_netlink.c:1361) 
[4559.221734][T31091] netlink_sendmsg (net/netlink/af_netlink.c:1905) 
[4559.221734][T31091] ____sys_sendmsg (net/socket.c:730 net/socket.c:745 net/socket.c:2585) 
[4559.221734][T31091] ___sys_sendmsg (net/socket.c:2641) 
[4559.221734][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
[4559.221734][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
| [4559.221734][T31091] ___sys_sendmsg (net/socket.c:2641) 
| [4559.221734][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
| [4559.221734][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
| [ 4559.221734][T31091]
| [ 4569.424146][T31091] unregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 5
[ 4569.424544][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 2/4 users at
[4569.424544][T31091] dst_init (net/core/dst.c:53) 
[4569.424544][T31091] dst_alloc (net/core/dst.c:96) 
[4569.424544][T31091] ip6_dst_alloc (net/ipv6/route.c:344) 
[4569.424544][T31091] ip6_rt_pcpu_alloc (net/ipv6/route.c:1381) 
[4569.424544][T31091] ip6_pol_route (net/ipv6/route.c:1429 net/ipv6/route.c:2266) 
[4569.424544][T31091] fib6_rule_lookup (./include/net/ip6_fib.h:616 net/ipv6/fib6_rules.c:121) 
[4569.424544][T31091] ip6_route_output_flags (net/ipv6/route.c:2638 net/ipv6/route.c:2650) 
[4569.424544][T31091] ip6_dst_lookup_tail.constprop.0 (net/ipv6/ip6_output.c:1147) 
[4569.424544][T31091] ip6_dst_lookup_flow (net/ipv6/ip6_output.c:1251) 
[4569.424544][T31091] udp_tunnel6_dst_lookup (net/ipv6/ip6_udp_tunnel.c:165 net/ipv6/ip6_udp_tunnel.c:135) 
[4569.424544][T31091] vxlan_xmit_one (drivers/net/vxlan/vxlan_core.c:2538 (discriminator 4)) vxlan
[4569.424544][T31091] vxlan_xmit (drivers/net/vxlan/vxlan_core.c:2803) vxlan
[4569.424544][T31091] dev_hard_start_xmit (./include/linux/netdevice.h:4894 ./include/linux/netdevice.h:4908 net/core/dev.c:3580 net/core/dev.c:3596) 
[4569.424544][T31091] __dev_queue_xmit (net/core/dev.h:185 net/core/dev.c:4404) 
[4569.424544][T31091] ip6_finish_output2 (./include/net/neighbour.h:540 net/ipv6/ip6_output.c:137) 
[4569.424544][T31091] ip6_finish_output (net/ipv6/ip6_output.c:211 net/ipv6/ip6_output.c:222) 
| [4569.424544][T31091] dev_hard_start_xmit (./include/linux/netdevice.h:4894 ./include/linux/netdevice.h:4908 net/core/dev.c:3580 net/core/dev.c:3596) 
| [4569.424544][T31091] __dev_queue_xmit (net/core/dev.h:185 net/core/dev.c:4404) 
| [4569.424544][T31091] ip6_finish_output2 (./include/net/neighbour.h:540 net/ipv6/ip6_output.c:137) 
| [4569.424544][T31091] ip6_finish_output (net/ipv6/ip6_output.c:211 net/ipv6/ip6_output.c:222) 
| [ 4569.424544][T31091]
[ 4569.426869][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 1/4 users at
[4569.426869][T31091] netdev_get_by_index (net/core/dev.c:916) 
[4569.426869][T31091] fib6_nh_init (net/ipv6/route.c:3542) 
[4569.426869][T31091] nh_create_ipv6 (net/ipv4/nexthop.c:2827) 
[4569.426869][T31091] nexthop_create (net/ipv4/nexthop.c:2878) 
[4569.426869][T31091] rtm_new_nexthop (net/ipv4/nexthop.c:2920 net/ipv4/nexthop.c:3206) 
[4569.426869][T31091] rtnetlink_rcv_msg (net/core/rtnetlink.c:6598) 
[4569.426869][T31091] netlink_rcv_skb (net/netlink/af_netlink.c:2564) 
[4569.426869][T31091] netlink_unicast (net/netlink/af_netlink.c:1335 net/netlink/af_netlink.c:1361) 
[4569.426869][T31091] netlink_sendmsg (net/netlink/af_netlink.c:1905) 
[4569.426869][T31091] ____sys_sendmsg (net/socket.c:730 net/socket.c:745 net/socket.c:2585) 
[4569.426869][T31091] ___sys_sendmsg (net/socket.c:2641) 
[4569.426869][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
[4569.426869][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[4569.426869][T31091] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
| [4569.426869][T31091] ___sys_sendmsg (net/socket.c:2641) 
| [4569.426869][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 
| [4569.426869][T31091] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
| [4569.426869][T31091] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
| [ 4569.426869][T31091]
[ 4569.428816][T31091] ref_tracker: veth_A-R1@ffff88800754c5e0 has 1/4 users at
[4569.428816][T31091] ipv6_add_dev (net/ipv6/addrconf.c:344 net/ipv6/addrconf.c:409) 
[4569.428816][T31091] addrconf_notify (net/ipv6/addrconf.c:3653) 
[4569.428816][T31091] notifier_call_chain (kernel/notifier.c:93 (discriminator 2)) 
[4569.428816][T31091] register_netdevice (./include/linux/notifier.h:207 net/core/dev.c:10436) 
[4569.428816][T31091] veth_newlink (drivers/net/veth.c:1860) 
[4569.428816][T31091] rtnl_newlink_create (net/core/rtnetlink.c:3513) 
[4569.428816][T31091] __rtnl_newlink (net/core/rtnetlink.c:3733) 
[4569.428816][T31091] rtnl_newlink (net/core/rtnetlink.c:3747) 
[4569.428816][T31091] rtnetlink_rcv_msg (net/core/rtnetlink.c:6598) 
[4569.428816][T31091] netlink_rcv_skb (net/netlink/af_netlink.c:2564) 
[4569.428816][T31091] netlink_unicast (net/netlink/af_netlink.c:1335 net/netlink/af_netlink.c:1361) 
[4569.428816][T31091] netlink_sendmsg (net/netlink/af_netlink.c:1905) 
[4569.428816][T31091] ____sys_sendmsg (net/socket.c:730 net/socket.c:745 net/socket.c:2585) 
[4569.428816][T31091] ___sys_sendmsg (net/socket.c:2641) 
[4569.428816][T31091] __sys_sendmsg (./include/linux/file.h:34 net/socket.c:2670) 


Finger prints:
dst_init:dst_alloc:ip6_dst_alloc:ip6_rt_pcpu_alloc:ip6_pol_route
dev_hard_start_xmit:__dev_queue_xmit:ip6_finish_output2:ip6_finish_output:netdev_get_by_index
___sys_sendmsg:__sys_sendmsg:do_syscall_64:ipv6_add_dev:addrconf_notify
___sys_sendmsg:__sys_sendmsg:do_syscall_64:dst_init:dst_alloc
dev_hard_start_xmit:__dev_queue_xmit:ip6_finish_output2:ip6_finish_output:netdev_get_by_index
___sys_sendmsg:__sys_sendmsg:do_syscall_64:ipv6_add_dev:addrconf_notify