Systems and methods for running a legacy 32-bit x86 virtual machine on a 64-bit x86 processor
US7260702B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2004 |
| Grant date | Aug 21, 2007 |
| Priority date | — |
| Expiry date | Oct 9, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/1004
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a virtualized computing systems and methods for transitioning in real time between LONG SUPER-MODE and LEGACY SUPER-MODE in the x86-64 architecture. In doing so, a virtual machine, which relies on the traditional 32-bit modes, i.e., REAL MODE and PROTECTED MODE (V86 SUB-MODE, RING-0 SUB-MODE, and RING-3 SUB-MODE), is able to run alongside other applications on x86-64 computer hardware (i.e., 64-bit). The method of performing a temporary processor mode context switch includes the steps of the virtual machine monitor's setting up a “virtual=real” page, placing the transition code for performing the processor mode context switch on this page, jumping to this page, disabling the memory management unit (MMU) of the x86-64 computer hardware, modifying the mode control register to set either the LONG SUPER-MODE bit or LEGACY SUPER-MODE bit, loading a new page table, and reactivating the MMU of the x86-64 computer hardware.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.