Granted Patent B1

US 8,127,292 · App. 12/143,893 · Granted Feb 28, 2012

Abstract

Claims (47)

1. A computer system comprising:

a processor;

a random-access memory (RAM) operatively coupled to the processor;

a first portion of a Hypervisor loaded into the memory as a part of an Extensible Firmware Interface upon start up and prior to loading of an operating system, wherein the first portion is responsible for context switching, at least a part of interrupt handling, and memory protection fault handling,

wherein the first portion of the Hypervisor runs on a root level;

an operating system loaded into a highest non-root privilege level;

a second portion of the Hypervisor loaded into operating system space together with the operating system, and running on the highest non-root privilege level;

a Virtual Machine Monitor (VMM) running on the highest privilege level,

wherein the second portion of the Hypervisor is responsible for any of (a) servicing the VMM, (b) enabling communication between code launched on non-root level with the first portion of the Hypervisor to perform security checks of trusted code portions of the VMM and to enable root mode for the code portions if allowable; and

at least one Virtual Machine (VM) running on a user level under control of the VMM.

2. The system of claim 1 , wherein the data needed for execution of the two Hypervisor portions is obtained from EFI.

3. The system of claim 1 , wherein Trusted Execution technology (TXT) is used for protection of the first Hypervisor portion.

4. The system of claim 1 , wherein:

trusted code runs on non-root level;

the first portion of the Hypervisor verifies trusted code portions during their loading or launch time; and

the trusted code is executed on root level.

5. The system of claim 4 , wherein Intel Trusted Execution technology (TXT) is used for protection of trusted code portions.

6. The system of claim 1 , wherein the VMM is de-privileged to non-root level 0 and the VM is launched on non-root level 3.

7. The system of claim 4 , wherein the VMM is launched on root level as trusted code portions.

8. The system of claim 7 , wherein the primary OS is de-privileged to non-root level.

9. A computer system comprising:

a processor;

a memory operatively coupled to the processor;

an Extensible Firmware Interface (EFI) as a layer between the computing system's firmware, hardware, and the operating system;

a first portion of a Hypervisor loaded into the memory as a part of the Extensible Firmware Interface upon start up and prior to loading of an operating system, wherein the first portion is responsible for organizing root and non-root contexts and switching between the root and non-root contexts, unprivileged event (interrupt) handling, and memory protection fault handling,

wherein the first portion of the Hypervisor runs on a root level;

an operating system loaded into a highest non-root level;

a second portion of the Hypervisor loaded into operating system space together with the operating system (OS), and running on the same privilege level as the OS,

wherein the second portion of the Hypervisor is responsible for enabling communication between code launched on non-root level with the first portion to perform security checks of trusted code portions of a Virtual Machine Monitor and to enable root mode for the code portions if allowable; and

a Virtual Machine running on a user level under control of the Virtual Machine Monitor.

10. The system of claim 8 , wherein the two Hypervisor portions are combined in a single EFI.

11. The system of claim 8 , wherein Trusted Execution technology (TXT) is used for protection of the first Hypervisor portion.

12. The system of claim 8 , wherein:

trusted code runs on non-root level;

the first portion of the Hypervisor verifies trusted code portions during their loading or launch time; and

the trusted code can be executed on root level.

13. The system of claim 11 , wherein Intel Trusted Execution technology (TXT) is used for protection of trusted code portions.

14. The system of claim 8 , wherein Virtual Machine Monitor (VMM) is launched through the Hypervisor.

15. The system of claim 13 , wherein the VMM is launched on non-root level 0.

16. A method for virtualizing a computer system, the method comprising:

loading a first portion of a Hypervisor into a memory of the computer system as a part of an Extensible Firmware Interface upon start up and prior to loading of an operating system, wherein the first portion is responsible for context switching, at least a part of interrupt handling, and memory protection fault handling,

wherein the first portion of the Hypervisor runs on a root level;

loading an operating system into a highest non-root privilege level;

loading a second portion of the Hypervisor into operating system space together with the operating system, and so that the second portion runs on the highest non-root privilege level;

starting a Virtual Machine Monitor (VMM) on the highest non-root privilege level,

wherein the second portion of the Hypervisor is responsible for any of (a) servicing the VMM, (b) enabling communication between code launched on non-root level with the first portion of the Hypervisor to perform security checks of trusted code portions of the VMM and to enable root mode for the code portions if allowable; and

starting at least one Virtual Machine on a user level under control of the VMM.

Assignments (9)