unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: netdev@ffff888029520610 has 1/1 users at
     dst_init+0xd9/0x450
     dst_alloc+0x12a/0x170
     rt_dst_clone+0x52/0x680
     ip_mc_finish_output+0xec/0x250
     ip_mc_output+0x3a3/0x590
     iptunnel_xmit+0x592/0xa40
     udp_tunnel_xmit_skb+0x26e/0x3c0
     tipc_udp_xmit+0x7bd/0xaa0
     tipc_udp_send_msg+0x27f/0x3f0
     tipc_bearer_xmit_skb+0x2b3/0x400
     __tipc_nl_bearer_enable+0x1044/0x13f0
     tipc_nl_bearer_enable+0x22/0x40
     genl_family_rcv_msg_doit+0x215/0x300
     genl_rcv_msg+0x60e/0x790
     netlink_rcv_skb+0x208/0x470
     genl_rcv+0x28/0x40

