Patent ID: 7913226

Claim:
A method of using a virtual machine monitor and an operating system on computer hardware in a computer, the method comprising: booting the operating system on the computer hardware such that the operating system has direct control of at least a portion of the computer hardware including a central processing unit (CPU), a physical memory, and an input/output (I/O) device; interposing the virtual machine monitor between the computer hardware and the operating system at runtime, wherein runtime includes a period of execution in the computer after booting and before shutdown of the computer, wherein the interposing occurs after booting of the computer, and wherein interposing the virtual machine monitor gives the virtual machine monitor direct control of the at least a portion of the computer hardware such that the operating system no longer has direct control of the at least a portion of the computer hardware; and devirtualizing the at least a portion of the computer hardware at runtime after the virtual machine monitor has been interposed at runtime, wherein devirtualizing the at least a portion of the computer hardware comprises stopping the virtual machine monitor such that the operating system resumes having direct control of the at least a portion of the computer hardware.