Computer system with dual operating modes
US7849311B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 15, 2005 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Oct 7, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2221/2105
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention is a system that switches between non-secure and secure modes by making processes, applications and data for the non-active mode unavailable to the active mode. That is, non-secure processes, applications and data are not accessible when in the secure mode and visa versa. This is accomplished by creating dual hash tables where one table is used for secure processes and one for non-secure processes. A hash table pointer is changed to point to the table corresponding to the mode. The path-name look-up function that traverses the path name tree to obtain a device or file pointer is also restricted to allow traversal to only secure devices and file pointers when in the secure mode and only to non-secure devices and files in the non-secure mode. The process thread run queue is modified to include a state flag for each process that indicates whether the process is a secure or non-secure process. A process scheduler traverses the queue and only allocates time to processes that have a state flag that matches the current mode. Running processes are marked to be idled and are flagged as unrunnable, depending on the security mode, when the process reaches an intercept po…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.