1. A method of directly sharing physical memory between processes executing on separate processor cores, each of the processes having its own respective top level address table, the method comprising: loading a plurality of processes into physical memory for execution on a corresponding plurality of processor cores sharing the physical memory; mapping an address space to each of the processes by populating a first entry in the respective top level virtual address table for each of the processes; and cross-mapping the address space of each of the processes into each of the other processes by populating one or more subsequent entries of each of the top level virtual address tables with the first entry in the top level virtual address table from other processes.