Switching between multiple software entities using different operating modes of a processor in a computer system
US7478388B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 2004 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Feb 20, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/45554
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A processor has multiple operating modes, such as the long/compatibility mode, the long/64-bit mode and the legacy modes of the x86-64 microprocessor. Different software entities execute in different ones of these operating modes. A switching routine is implemented to switch from one operating mode to another and to transfer control from one software entity to another. The software entities may be, for example, a host operating system and a virtual machine monitor. Thus, for example, a virtual computer system may comprise a 64-bit host operating system and a 32-bit virtual machine monitor, executing on an x86-64 microprocessor in long mode and legacy mode, respectively, with the virtual machine monitor supporting an x86 virtual machine. The switching routine may be implemented partially or completely in an identity-mapped memory page. Execution of the switching routine may be initiated by a driver that is installed in the host operating system of a virtual computer system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.