Abstract: Embodiments of apparatuses, methods, and systems for processing interrupts in a layered virtualization architecture are disclosed. In one embodiment, an apparatus includes a recognition logic, window logic, and evaluation logic. The event logic is to recognize an interrupt request. The window logic is to determine whether an interrupt window is open. The evaluation logic is to determine whether to transfer control to one of at least two virtual machine monitors in response to the interrupt request if the interrupt window is open.

Abstract: In one embodiment of the present invention, a method includes switching between a first address space and a second address space, determining if the second address space exists in a list of address spaces; and maintaining entries of the first address space in a translation buffer after the switching. In such manner, overhead associated with such a context switch may be reduced.

Abstract: A processor including a virtualization system of the processor with a memory virtualization support system to map a reference to guest-physical memory made by guest software executable on a virtual machine which in turn is executable on a host machine in which the processor is operable to a reference to host-physical memory of the host machine.

Abstract: A technique to improve the performance of virtualized input/output (I/O) resources of a microprocessor within a virtual machine environment. More specifically, embodiments of the invention enable accesses of virtualized I/O resources to be made by guest software without necessarily invoking host software. Furthermore, embodiments of the invention enable more efficient delivery of interrupts to guest software by alleviating the need for host software to be invoked in the delivery process.

Abstract: Apparatus and methods for reducing information leakage between processes sharing a cache are disclosed. In one embodiment, an apparatus includes execution logic, a cache memory, and cache security logic. The execution unit is to execute a plurality of processes. The cache memory is to be shared between the plurality of processes. The cache security logic is to cause a stored cache state to be loaded into the cache memory.

Abstract: In one embodiment, a processor mode is provided for guest software. The processor mode enables the guest software to operate at a privilege level intended by the guest software. When the guest software attempts to perform an operation restricted by the processor mode, the processor mode is exited to transfer control over the operation to a virtual-machine monitor, which runs outside this processor mode.

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: Embodiments of apparatuses and methods for correcting intermittent errors in data storage structures are disclosed. In one embodiment, an apparatus includes a data storage location, error detection logic, inverting logic, control logic, operating logic, and evaluation logic. The error detection logic is to detect an error in a data value read from the data storage location. The inverting logic is to invert the erroneous data value to produce an inverted erroneous data value. The control logic is to cause the inverted erroneous data value to be stored in the data storage location and subsequently read from the data storage location to produce an operand value. The operating logic is to perform a logical operation using the erroneous data value and the operand value. The evaluation logic is to evaluate the result to determine if the error is a soft error.

Abstract: Embodiments of apparatuses and methods for reducing the uncorrectable error rate in a lockstepped dual-modular redundancy system are disclosed. In one embodiment, an apparatus includes two processor cores, a micro-checker, a global checker, and fault logic. The micro-checker is to detect whether a value from a structure in one core matches a value from the corresponding structure in the other core. The global checker is to detect lockstep failures between the two cores. The fault logic is to cause the two cores to be resynchronized if there is a lockstep error but the micro-checker has detected a mismatch.

Abstract: Performing a hash algorithm in a processor architecture to alleviate performance bottlenecks and improve overall algorithm performance. In one embodiment of the invention, the hash algorithm is pipelined within the processor architecture.

Abstract: A method and apparatus for providing a low power mode for a processor while maintaining snoop throughput are disclosed. In one embodiment, an apparatus includes a cache, a processor, and a frequency controller. The frequency controller is to operate the apparatus in a low power mode in which the operating frequency of the cache is higher than the operating frequency of the processor.

Abstract: Embodiments of apparatuses and methods for multiplicand shifting in a linear systolic array modular multiplier are disclosed. In one embodiment, an apparatus includes two processing elements of a linear systolic array. One processing element includes multiplication logic, multiplicand shift logic, an adder, modulus logic, and modulus shift logic. The multiplication logic is to multiply a word of the multiplicand and a bit of the multiplier to generate a product. The multiplicand shift logic is to shift the word of the multiplicand. The adder is to add the product to a first running sum to generate a second running sum. The modulus logic is to conditionally add a word of a modulus and the second running sum. The modulus shift logic is to shift the word of the modulus. The next processing element includes logic to multiply the shifted word of the multiplicand and the next bit of the multiplier.

Abstract: Embodiments of apparatuses, methods, and systems for guest to host address translations for devices to access memory in a partitioned system are disclosed. In one embodiment, an apparatus includes an interface, partitioning logic, first address translation logic, and second address translation logic. The interface is to receive a request from a device to access memory in a partitioned system. The partitioning logic is to determine whether the device is assigned to a first partition or a second partition. The first address translation logic is to translate a first guest address to a first host address in the first partition. The second address translation logic is to translate a second guest address to a second host address in the second partition.

Abstract: Embodiments of apparatuses, methods, and systems for in situ processor margin testing are disclosed. In one embodiment, an apparatus includes virtual machine control logic and operating point control logic. The virtual machine control logic is to transfer control of the apparatus between a virtual machine monitor and a guest. The operating point control logic is to set the operating point of the apparatus in connection with a transfer of control of the apparatus to the virtual machine monitor.

Abstract: A technique to detect errors in a computer system. More particularly, at least one embodiment of the invention relates to using redundant virtual machines and comparison logic to detect errors occurring in input/output (I/O) operations in a computer system.

Abstract: Techniques for handling certain virtualization events occurring within a virtual machine environment. More particularly, at least one embodiment of the invention pertains to handling events related to the sub-operating system mode using a dedicated virtual machine monitor (VMM) called the system management mode VMM (SVMM), which exists in a separate portion of memory from a main virtual machine monitor (MVMM) used to handle virtualization events other than those related to the sub-operating system mode. In at least one embodiment, a technique for initializing and managing transitions to and from the SVMM is disclosed.

Abstract: Embodiments of apparatuses and methods for reducing the soft error vulnerability of stored data are disclosed. In one embodiment, an apparatus includes storage logic, determination logic, and selection logic. The determination logic is to determine a condition of a dataword. The storage logic includes logic to store a first portion of the dataword, a second portion of the dataword, and a result generated by the determination logic. The selection logic is to select, based on the contents of the storage logic to store the result, either the contents of the storage logic to store the second portion of the dataword, or a replacement value. The replacement value depends on the contents of a predetermined bit of the storage logic to store the first portion of the dataword.

Abstract: A method and apparatus for initiating secure operations in a microprocessor system is described. In one embodiment, one initiating logical processor initiates the process by halting the execution of the other logical processors, and then loading initialization and secure virtual machine monitor software into memory. The initiating processor then loads the initialization software into secure memory for authentication and execution. The initialization software then authenticates and registers the secure virtual machine monitor software prior to secure system operations.

Abstract: Power management commands from virtual machines (VMs) in a VM environment may be trapped by a VM monitor. Depending on the current power states of the other VMs in the VM environment, the VMM may emulate increase or decrease in available resources as applied to the VM issuing the power management commands. The VMM may modify the actual hardware resources available in a platform when such modification may not affect the current power states of the VMs in the VM environment.

Abstract: A memory region access management technique. More particularly, at least one embodiment of the invention relates to a technique to partition memory between two or more operating systems or other software running on one or more processors.