Privilege level checking instruction for implementing a secure hierarchical computer system
US4809160A · kind A · utility
150Cited by
6References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1985 |
| Grant date | Feb 28, 1989 |
| Priority date | — |
| Expiry date | Oct 28, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/45537
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A low overhead way for insuring that only routines of sufficient privilege can execute on a secured page of memory in an hierarchial computer system, and for raising the privilege level of a low privilege process in an orderly and secure way is presented. This is done through the execution of a single "gateway" branch instruction standing between a procedure call by a lower privileged routine, such as a user program, and an operating system itself.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.