Patent ID: 7937701
Filing Date: 2011-05-03
Classification: G06F

Abstract:
1. A method for bi-directional communication between a policy virtual machine (VM) and a Virtual Machine Manager (VMM) on a VM host comprising: designating one of a plurality of VMs on the VM host as the policy VM, the policy VM dictating policies of the VM host and having access to the VM host's hardware and the VM host's device configuration and power management subsystem tables; allocating a memory region to the policy VM; designating a portion of the memory region as a mailbox accessible by the policy VM and the VMM; enabling the policy VM to place information in the mailbox from a first method executed by the policy VM's advanced configuration and power interface (ACPI) subsystem to produce an event that is detectable by the VMM; enhancing the VMM to virtualize ACPI General Purpose Event (GPE) register blocks; enabling the VMM to communicate with the policy VM by inserting in the mailbox a second method for execution by the policy VM's ACPI subsystems; and the enabling the VMM to further insert an interrupt into the policy VM, the VMM injecting a System Control Interrupt (SCI) into a guest operating system (OS) in the policy VM, the guest OS forwarding the SCI to the ACPI subsystem to determine a cause of the GPE by examining a GPE register block, the VMM producing a virtual GPE register block with a status register having an active status, the ACPI subsystem examining the virtual GPE register block with the status register having the active status, and the ACPI subsystem invoking an ACPI control method to handle the SCI based on the GPE register block with the status register having the active status.