r0 = socket$inet6_udp(0xa, 0x2, 0x0) ioctl$sock_inet6_SIOCDELRT(r0, 0x890c, &(0x7f0000000000)={@initdev={0xfe, 0x88, '\x00', 0x0, 0x0}, @mcast2, @empty, 0x0, 0xbffd, 0x0, 0x0, 0x0, 0x1100000})