METHOD AND APPARATUS FOR DETECTING MEMORY SEGMENT VIOLATIONS IN A COMPUTER SYSTEM

摘要

A protection mechanism for a microprocessor (100) has multiple privilege levels for tasks running on the microprocessor. A memory control unit (115) for the microprocessor (100) includes segment registers (200C, 200S, 200D, 200E, 200F, 200G) that identify segments (502-512) of memory (500) assigned to various tasks. When a segment register is loaded with the address of a new segment for a task, the protection mechanism within the memory control unit (115) compares the privilege level of the task requesting the segment with the privilege level of the requested memory segment and determines whether the requested memory segment can be assigned to the requesting task. The relationship between the privilege levels is programmable to provide flexibility in generating privilege faults.