Patent ID: 7904903

Claim:
A virtualization platform comprising: a processor having a plurality of register sets; a plurality of virtual machines (VM) to run on the processor, each VM to run in a guest operating system, each VM associated with at least one virtual machine control structure (VMCS), the VMCS having fields indicating trap events for processor instructions accessing selected register sets; a trap mechanism corresponding to each VM to exit from a running VM responsive to occurrence of a predetermined trap event in the VM, the trap mechanism to set a field in the VM's VMCS indicating that the predetermined trap event has occurred in the VM; and a virtual machine monitor (VMM) to schedule and switch context among the plurality of virtual machines, wherein the VMM is to determine which of the plurality of register sets are to be saved and restored upon context switching among the plurality of VMs, the determination being based at least in part on the trap event fields in the VM's VMCS.