MEMORY PROTECTION MECHANISM FOR A DISTRIBUTED SHARED MEMORY MULTIPROCESSOR WITH INTEGRATED MESSAGE PASSING SUPPORT

摘要

The present invention relates generally to efficient message passing support and memory access protections in scalable shared memory multiprocessing computer systems. In a multiprocessor system, processors need to communicate with one another to coordinate their work. Prior art multiprocessors only permit message passing or unprotected direct memory access. The present invention allows direct memory access with protection. The mechanism of the present invention permits processors to directly access each other's memory while retaining protection against faulty software or hardware. Security in the face of malicious intent of the communicating software is not maintained in the preferred embodiment, although a variation of the mechanism provides additional protection against malicious software albeit at the expense of slightly more complex hardware.