Key-controlled object-based memory protection
US7890727B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 2008 |
| Grant date | Feb 15, 2011 |
| Priority date | — |
| Expiry date | May 12, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1466
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A processing unit includes an authority check for controlling access by the processing unit to pages of memory according to whether a hardware protection key set currently loaded in an authority mask register allows access to the pages. In particular, each page of memory is assigned a page key number that indexes into the hardware protection key set. The currently loaded hardware protection key set specifies those page key numbers that are currently accessible to the processing unit for the execution context. Each hardware key within the hardware protection key set is associated with a particular data object or group of data objects. Thus, effectively, the currently loaded hardware protection key set identifies which data objects or groups of data objects are currently accessible. Software keys are assigned to data objects and dynamically mapped to hardware protection key sets, such that when a module is called, the software keys assigned to that module are mapped to the hardware protection key set to be loaded for controlling current access to memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.