Patent · US Expired

Code and thread differential addressing via multiplex page maps

US7073173B1 · kind B1 · utility

31Cited by
3References
77Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 26, 2001
Grant dateJul 4, 2006
Priority date
Expiry dateJul 22, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/1491
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Described is a system and method whereby processes may have multiple memory maps associated therewith to provide curtained memory and overcome other memory-related problems. Multiple maps are used to restrict memory access of existing code such as drivers, without changing that code, and without changing existing microprocessors. A thread of a process is associated with one memory map at a time, which by mapping to different memory locations, provides memory isolation without requiring a process switch. Memory isolation may be combined with controlled, closed memory map switching performed only by trusted code, to ensure that some protected memory is inaccessible to all but the trusted code (curtained memory). Map switching among multiple maps eliminates the need to change a process in order to access different memory, thereby allowing expanded memory addressing in a single process and isolating untrusted code run in process from certain memory of that process.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.