Abstract: In one embodiment, a request to transition control to a virtual machine (VM) is received from a virtual machine monitor (VMM) and a determination is made as to whether the VMM has requested a delivery of a fault to the VM. If the determination is positive, the fault is delivered to the VM when control is transitioned to the VM.

Abstract: Methods and systems are provided to control transitions between a virtual machine (VM) and Virtual Machine Monitor (VMM). A processor uses state action indicators to load and/or store associated elements of machine state before completing the transition. The state action indicators may be stored in a Virtual Machine Control Structure (VMCS), predetermined, and/or calculated dynamically. In some embodiments, the values loaded can be directly acquired from the VMCS, predetermined and/or calculated dynamically. In some embodiments, the values stored may be acquired directly from machine state, predetermined and/or calculated dynamically.

Abstract: Methods and systems are provided to control the execution of a virtual machine (VM). A VM Monitor (VMM) accesses VM Control Structures (VMCS) indirectly through access instructions passed to a processor. In one embodiment, the access instructions include VMCS component identifiers used by the processor to determine the appropriate storage location for the VMCS components. The processor identifies the appropriate storage location for the VMCS component within the processor storage or within memory.

Abstract: In one embodiment, an occurrence of an interrupt is identified during the operation of guest software. Further, a determination is made as to whether the interrupt is managed by guest software. The determination depends on the current value of an interrupt control indicator. If the interrupt is not managed by guest software, control is transitioned to a virtual machine monitor (VMM) if the VMM is ready to receive control.

Abstract: In one embodiment, when it is determined that a modification of content of an active address translation data structure is required, an entry in the active address translation data structure is modified to conform to a corresponding entry in a guest address translation data structure. During the modification, a bit field including one or more access control indicators in the entry of the active address translation data structure is not overwritten with corresponding data from the guest address translation data structure.

Abstract: In one embodiment, fault information relating to a fault associated with the operation of guest software is received. Further, a determination is made as to whether the fault information satisfies one or more fault filtering criteria. If the determination is positive, the guest software is permitted to disregard the fault.

Abstract: In one embodiment, fault information relating to a fault associated with the operation of guest software is received. Further, a determination is made as to whether the fault information satisfies one or more filtering criterion. If the determination is positive, control remains with the guest software and is not transferred to the virtual machine monitor (VMM).

Abstract: In one embodiment, a command pertaining to one or more portions of a register is received from guest software. Further, a determination is made as to whether the guest software has access to all of the requested portions of the register based on indicators within a mask field that correspond to the requested portions of the register. If the guest software has access to all of the requested portions of the register, the command received from the guest software is executed on the requested portions of the register.

Abstract: Transitions among schedulable entities executing in a computer system are tracked in computer hardware or in a virtual machine monitor. In one aspect, the schedulable entities are operating system processes and threads, virtual machines, and instruction streams executing on the hardware. In another aspect, the schedulable entities are processes or threads executing within the virtual machines under the control of the virtual machine monitor. The virtual machine monitor derives scheduling information from the transitions to enable a virtual machine system to guarantee adequate scheduling quality of service to real-time applications executing in virtual machines that contain both real-time and non-real-time applications. In still another aspect, a parent virtual machine monitor in a recursive virtualization system can use the scheduling information to schedule a child virtual machine monitor that controls multiple virtual machines.

Abstract: A method and apparatus for constructing host processor soft devices independent of the host processor operating system are provided. In one embodiment, a driver of a soft device is implemented in a virtual machine monitor (VMM), and the soft device is made available for use by one or more virtual machines coupled to the VMM. In an alternative embodiment, a software component of a soft device is implemented in a first virtual machine that is coupled to a VMM, and the soft device is made available for use by a second virtual machine coupled to the VMM.

Abstract: In one embodiment, a method for supporting address translation in a virtual-machine environment includes creating a guest translation data structure to be used by a guest operating system for address translation operations, creating an active translation data structure based on the guest translation data structure, and periodically modifying the content of the active translation data structure to conform to the content of the guest translations data structure. The content of the active translation data structure is used by a processor to cache address translations in a translation-lookaside buffer (TLB).

Abstract: In one embodiment, a method for providing power management via virtualization includes monitoring the utilization of a host platform device by one or more virtual machines and managing power consumption of the host platform device based on the results of monitoring.