Program received signal SIGSEGV, Segmentation fault.
0x00594fd8 in nl_sock_cow__ (sock=0x19) at lib/netlink-socket.c:673
673	    if (!sock->dump) {
(gdb) bt
#0  0x00594fd8 in nl_sock_cow__ (sock=0x19) at lib/netlink-socket.c:673
#1  0x005940c0 in nl_sock_recv (sock=0x19, bufp=0x7fbeb3f0, wait=false)
    at lib/netlink-socket.c:390
#2  0x0057900c in dpif_linux_recv (dpif_=0x61ed88, upcall=0x7fbeb560)
    at lib/dpif-linux.c:1067
#3  0x004d083c in dpif_recv (dpif=0x61ed88, upcall=0x7fbeb560)
    at lib/dpif.c:1065
#4  0x004861f8 in handle_upcalls (ofproto=0x61df08, max_batch=50)
    at ofproto/ofproto-dpif.c:2860
#5  0x0047b7e4 in run_fast (ofproto_=0x61df10) at ofproto/ofproto-dpif.c:779
#6  0x0047b91c in run (ofproto_=0x61df10) at ofproto/ofproto-dpif.c:801
#7  0x0046b694 in ofproto_run (p=0x61df10) at ofproto/ofproto.c:1035
#8  0x00427f18 in bridge_run () at vswitchd/bridge.c:2059
#9  0x004322fc in main (argc=1, argv=0x7fbebce4) at vswitchd/ovs-vswitchd.c:97