Abstract: An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

Abstract: An apparatus and method are described for authenticating extended service microcode updates. For example, one embodiment of a method comprises: storing extended service microcode update (MCU) in a memory of a processor; reading processor signature data, platform identification data, and processor extended service data from one or more registers of the processor; identifying MCU extended service period data based on processor signature data and platform identification data; determining whether to apply the extended service MCU on the processor based on a comparison between the MCU extended service period data and the processor extended service data.

Abstract: Methods and apparatuses relating to mitigations for speculative execution side channels are described. Speculative execution hardware and environments that utilize the mitigations are also described. For example, three indirect branch control mechanisms and their associated hardware are discussed herein: (i) indirect branch restricted speculation (IBRS) to restrict speculation of indirect branches, (ii) single thread indirect branch predictors (STIBP) to prevent indirect branch predictions from being controlled by a sibling thread, and (iii) indirect branch predictor barrier (IBPB) to prevent indirect branch predictions after the barrier from being controlled by software executed before the barrier.

Abstract: Systems, methods, and devices are provided for identification of model-specific behavior relating to microcode update capabilities of a processor to enable efficient microcode updates across a range of different machines. A system may include a first processor core and a second processor core. A register of the system may indicate a hardware capability of the system to perform a uniform microcode update by propagating a microcode update from the first processor core to a second processor core.

Abstract: Methods and apparatuses relating to mitigations for speculative execution side channels are described. Speculative execution hardware and environments that utilize the mitigations are also described. For example, three indirect branch control mechanisms and their associated hardware are discussed herein: (i) indirect branch restricted speculation (IBRS) to restrict speculation of indirect branches, (ii) single thread indirect branch predictors (STIBP) to prevent indirect branch predictions from being controlled by a sibling thread, and (iii) indirect branch predictor barrier (IBPB) to prevent indirect branch predictions after the barrier from being controlled by software executed before the barrier.

Abstract: A processor includes a first model specific register (MSR); and memory encryption circuitry to receive a request to access a memory, determine if a key identifier (ID) of the request is zero, and if the key ID is zero, to bypass data encryption when the request is to write data to the memory and to bypass memory decryption when the request is to read data from the memory and when a selected bit of the first MSR is set, and if the selected bit of the first MSR is not set, to encrypt write data when the request is to write data or decrypt data in a read response when the request is to read data, with a key associated with the key ID equal to zero.

Abstract: Methods and apparatuses relating to mitigations for speculative execution side channels are described. Speculative execution hardware and environments that utilize the mitigations are also described. For example, three indirect branch control mechanisms and their associated hardware are discussed herein: (i) indirect branch restricted speculation (IBRS) to restrict speculation of indirect branches, (ii) single thread indirect branch predictors (STIBP) to prevent indirect branch predictions from being controlled by a sibling thread, and (iii) indirect branch predictor barrier (IBPB) to prevent indirect branch predictions after the barrier from being controlled by software executed before the barrier.

Abstract: Processors, methods, and systems for user-level interprocessor interrupts are described. In an embodiment, a processing system includes a memory and a processing core. The memory is to store an interrupt control data structure associated with a first application being executed by the processing system. The processing core includes an instruction decoder to decode a first instruction, invoked by a second application, to send an interprocessor interrupt to the first application; and, in response to the decoded instruction, is to determine that an identifier of the interprocessor interrupt matches a notification interrupt vector associated with the first application; set, in the interrupt control data structure, a pending interrupt flag corresponding to an identifier of the interprocessor interrupt; and invoke an interrupt handler for the interprocessor interrupt identified by the interrupt control data structure.

Abstract: An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

Abstract: Embodiments of apparatuses, methods, and systems for virtualization of interprocessor interrupts are disclosed. In an embodiment, an apparatus includes a plurality of processor cores; an interrupt controller register; and logic to, in response to a write from a virtual machine to the interrupt controller register, record an interprocessor interrupt in a first data structure configured by a virtual machine monitor and send a notification of the interprocessor interrupt to at least one of the plurality of processor cores.

Abstract: Systems, methods, and apparatuses relating to processor non-write-back capabilities are described. In one embodiment, a processor includes a plurality of logical processors, a control register comprising a non-write-back lock disable bit, a cache shared by the plurality of logical processors, a bus to couple the cache to a memory to service a memory request for the memory from the plurality of logical processors, and a memory controller to disable a non-write-back lock access of the bus for a read-modify-write type of the memory request issued by a logical processor of the plurality of logical processors when the non-write-back lock disable bit is set to a first value, and implement the non-write-back lock access of the bus for the read-modify-write type of the memory request when the non-write-back lock disable bit is set to a second value.

Abstract: A processor or system includes a processor core to execute a set of instructions to determine that a memory encryption mode is enabled. The memory encryption mode is to cause data stored to memory to be encrypted and data retrieved from the memory to be decrypted. The processor core is further to determine that a debug mode has been enabled and, responsive to a determination that the debug mode has been enabled, generate a second encryption key different than a first encryption key employed before reboot of a computing system. The processor core is further to transmit the second encryption key to a cryptographic engine for use in encryption and decryption of the data according to the memory encryption mode.

Abstract: An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

Abstract: A processor of an aspect includes a decode unit to decode a read from memory instruction. The read from memory instruction is to indicate a source memory operand and a destination storage location. The processor also includes an execution unit coupled with the decode unit. The execution unit, in response to the read from memory instruction, is to read data from the source memory operand, store an indication of defective data in an architecturally visible storage location, when the data is defective, and complete execution of the read from memory instruction without causing an exceptional condition, when the data is defective. Other processors, methods, systems, and instructions are disclosed.

Abstract: An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

Abstract: Systems, methods, and apparatuses relating to processor non-write-back capabilities are described. In one embodiment, a processor includes a plurality of logical processors, a control register comprising a non-write-back lock disable bit, a cache shared by the plurality of logical processors, a bus to couple the cache to a memory to service a memory request for the memory from the plurality of logical processors, and a memory controller to disable a non-write-back lock access of the bus for a read-modify-write type of the memory request issued by a logical processor of the plurality of logical processors when the non-write-back lock disable bit is set to a first value, and implement the non-write-back lock access of the bus for the read-modify-write type of the memory request when the non-write-back lock disable bit is set to a second value.

Abstract: Embodiment of this disclosure provides a mechanism to support hang detection and data recovery in microprocessor systems. In one embodiment, a processing device comprising a processing core and a crashlog unit operatively coupled to the core is provided. An indication of an unresponsive state in an execution of a pending instruction by the core is received. Responsive to receiving the indication, a crash log comprising data from registers of at least one of: a core region, a non-core region and a controller hub associated with the processing device is produced. Thereupon, the crash log is stored in a shared memory of a power management controller (PMC) associated with the controller hub.

Abstract: Methods and apparatuses relating to mitigations for speculative execution side channels are described. Speculative execution hardware and environments that utilize the mitigations are also described. For example, three indirect branch control mechanisms and their associated hardware are discussed herein: (i) indirect branch restricted speculation (IBRS) to restrict speculation of indirect branches, (ii) single thread indirect branch predictors (STIBP) to prevent indirect branch predictions from being controlled by a sibling thread, and (iii) indirect branch predictor barrier (IBPB) to prevent indirect branch predictions after the barrier from being controlled by software executed before the barrier.

Abstract: An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

Abstract: A heterogeneous processor architecture and a method of booting a heterogeneous processor is described. A processor according to one embodiment comprises: a set of large physical processor cores; a set of small physical processor cores having relatively lower performance processing capabilities and relatively lower power usage relative to the large physical processor cores; and a package unit, to enable a bootstrap processor. The bootstrap processor initializes the homogeneous physical processor cores, while the heterogeneous processor presents the appearance of a homogeneous processor to a system firmware interface.