Abstract: A processor includes an execution unit and a processing logic operatively coupled to the execution unit, the processing logic to: enter a first execution state and transition to a second execution state responsive to executing a control transfer instruction. Responsive to executing a target instruction of the control transfer instruction, the processing logic further transitions to the first execution state responsive to the target instruction being a control transfer termination instruction of a mode identical to a mode of the processing logic following the execution of the control transfer instruction; and raises an execution exception responsive to the target instruction being a control transfer termination instruction of a mode different than the mode of the processing logic following the execution of the control transfer instruction.

Abstract: Systems, methods, and apparatuses relating to instructions to reset software thread runtime property histories in a hardware processor are described. In one embodiment, a hardware processor includes a hardware guide scheduler comprising a plurality of software thread runtime property histories; a decoder to decode a single instruction into a decoded single instruction, the single instruction having a field that identifies a model-specific register; and an execution circuit to execute the decoded single instruction to check that an enable bit of the model-specific register is set, and when the enable bit is set, to reset the plurality of software thread runtime property histories of the hardware guide scheduler.

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 counter to store a cycle count that tracks a number of cycles between retirement of a first branch instruction and retirement of a second branch instruction during execution of a set of instructions. The processor further includes a stack of registers coupled to the counter, wherein the stack of registers is to store branch type information including: a first value of the counter when the first branch instruction is retired; a second value of the counter when the second branch instruction is retired; a first type information value indicating a type of the first branch instruction; and a second type information value indicating a type of the second branch instruction.

Abstract: Systems, methods, and apparatuses relating to instructions to reset software thread runtime property histories in a hardware processor are described. In one embodiment, a hardware processor includes a hardware guide scheduler comprising a plurality of software thread runtime property histories; a decoder to decode a single instruction into a decoded single instruction, the single instruction having a field that identifies a model-specific register; and an execution circuit to execute the decoded single instruction to check that an enable bit of the model-specific register is set, and when the enable bit is set, to reset the plurality of software thread runtime property histories of the hardware guide scheduler.

Abstract: Disclosed embodiments relate to encoded inline capabilities. In one example, a system includes a trusted execution environment (TEE) to partition an address space within a memory into a plurality of compartments each associated with code to execute a function, the TEE further to assign a message object in a heap to each compartment, receive a request from a first compartment to send a message block to a specified destination compartment, respond to the request by authenticating the request, generating a corresponding encoded capability, conveying the encoded capability to the destination compartment, and scheduling the destination compartment to respond to the request, and subsequently, respond to a check capability request from the destination compartment by checking the encoded capability and, when the check passes, providing a memory address to access the message block, and, otherwise, generating a fault, wherein each compartment is isolated from other compartments.

Abstract: Systems, methods, and apparatuses relating to instructions to compartmentalize memory accesses and execution (e.g., non-speculative and speculative) are described.

Abstract: In one embodiment, a processor includes: a plurality of registers; a front end circuit to fetch and decode a non-serializing register write instruction, the non-serializing register write instruction to cause a value to be stored in a first register of the plurality of registers; and an execution circuit coupled to the front end circuit. The execution circuit, in response to the non-serializing register write instruction, is to determine an amount of serialization for the non-serializing register write instruction and execute the non-serializing register write instruction according to the amount of serialization. Other embodiments are described and claimed.

Abstract: In one embodiment, a processor includes: a front end circuit to fetch and decode a read list instruction, the read list instruction to cause storage to a memory of a software-provided list of processor state information; and an execution circuit coupled to the front end circuit. The execution circuit, in response to the decoded read list instruction, is to read the processor state information stored in the processor and store each datum of the processor state information into an entry of a data table in the memory. Other embodiments are described and claimed.

Abstract: A processor includes a widest set of data registers that corresponds to a given logical processor. Each of the data registers of the widest set have a first width in bits. A decode unit that corresponds to the given logical processor is to decode instructions that specify the data registers of the widest set, and is to decode an atomic store to memory instruction. The atomic store to memory instruction is to indicate data that is to have a second width in bits that is wider than the first width in bits. The atomic store to memory instruction is to indicate memory address information associated with a memory location. An execution unit is coupled with the decode unit. The execution unit, in response to the atomic store to memory instruction, is to atomically store the indicated data to the memory location.

Abstract: Technologies disclosed herein provide cryptographic computing with cryptographically encoded pointers in multi-tenant environments. An example method comprises executing, by a trusted runtime, first instructions to generate a first address key for a private memory region in the memory and generate a first cryptographically encoded pointer to the private memory region in the memory. Generating the first cryptographically encoded pointer includes storing first context information associated with the private memory region in first bits of the first cryptographically encoded pointer and performing a cryptographic algorithm on a slice of a first linear address of the private memory region based, at least in part, on the first address key and a first tweak, the first tweak including the first context information. The method further includes permitting a first tenant in the multi-tenant environment to access the first address key and the first cryptographically encoded pointer to the private memory region.

Abstract: Systems, methods, and apparatuses relating to microarchitectural mechanisms for the prevention of side-channel attacks are disclosed herein. In one embodiment, a processor includes a core having a plurality of physical contexts to execute a plurality of threads, a plurality of structures shared by the plurality of threads, a context mapping structure to map context signatures to respective physical contexts of the plurality of physical contexts, each physical context to identify and differentiate state of the plurality of structures, and a context manager circuit to, when one or more of a plurality of fields that comprise a context signature is changed, search the context mapping structure for a match to another context signature, and when the match is found, a physical context associated with the match is set as an active physical context for the core.

Abstract: Systems, methods, and apparatuses relating to an instruction for operating system transparent instruction state management of new instructions for application threads are described. In one embodiment, a hardware processor includes a decoder to decode a single instruction into a decoded single instruction, and an execution circuit to execute the decoded single instruction to cause a context switch from a current state to a state comprising additional state data that is not supported by an execution environment of an operating system that executes on the hardware processor.

Abstract: Systems, methods, and apparatuses relating to instructions to reset software thread runtime property histories in a hardware processor are described. In one embodiment, a hardware processor includes a hardware guide scheduler comprising a plurality of software thread runtime property histories; a decoder to decode a single instruction into a decoded single instruction, the single instruction having a field that identifies a model-specific register; and an execution circuit to execute the decoded single instruction to check that an enable bit of the model-specific register is set, and when the enable bit is set, to reset the plurality of software thread runtime property histories of the hardware guide scheduler.

Abstract: Technologies disclosed herein provide cryptographic computing with cryptographically encoded pointers in multi-tenant environments. An example method comprises executing, by a trusted runtime, first instructions to generate a first address key for a private memory region in the memory and generate a first cryptographically encoded pointer to the private memory region in the memory. Generating the first cryptographically encoded pointer includes storing first context information associated with the private memory region in first bits of the first cryptographically encoded pointer and performing a cryptographic algorithm on a slice of a first linear address of the private memory region based, at least in part, on the first address key and a first tweak, the first tweak including the first context information. The method further includes permitting a first tenant in the multi-tenant environment to access the first address key and the first cryptographically encoded pointer to the private memory region.

Abstract: Technologies disclosed herein provide cryptographic computing with cryptographically encoded pointers in multi-tenant environments. An example method comprises executing, by a trusted runtime, first instructions to generate a first address key for a private memory region in the memory and generate a first cryptographically encoded pointer to the private memory region in the memory. Generating the first cryptographically encoded pointer includes storing first context information associated with the private memory region in first bits of the first cryptographically encoded pointer and performing a cryptographic algorithm on a slice of a first linear address of the private memory region based, at least in part, on the first address key and a first tweak, the first tweak including the first context information. The method further includes permitting a first tenant in the multi-tenant environment to access the first address key and the first cryptographically encoded pointer to the private memory region.

Abstract: Embodiments of an invention a processor architecture are disclosed. In an embodiment, a processor includes a decoder, an execution unit, a coherent cache, and an interconnect. The decoder is to decode an instruction to zero a cache line. The execution unit is to issue a write command to initiate a cache line sized write of zeros. The coherent cache is to receive the write command, to determine whether there is a hit in the coherent cache and whether a cache coherency protocol state of the hit cache line is a modified state or an exclusive state, to configure a cache line to indicate all zeros, and to issue the write command toward the interconnect. The interconnect is to, responsive to receipt of the write command, issue a snoop to each of a plurality of other coherent caches for which it must be determined if there is a hit.

Abstract: Embodiments for dynamically mitigating speculation vulnerabilities are disclosed. In an embodiment, an apparatus includes decode circuitry and execution circuitry coupled to the decode circuitry. The decode circuitry is to decode a register hardening instruction to mitigate vulnerability to a speculative execution attack. The execution circuitry is to be hardened in response to the register hardening instruction.

Abstract: Embodiments for dynamically mitigating speculation vulnerabilities are disclosed. In an embodiment, an apparatus includes decode circuitry and execution circuitry coupled to the decode circuitry. The decode circuitry is to decode a single instruction to mitigate vulnerability to a speculative execution attack. The execution circuitry is to be hardened in response to the single instruction.

Abstract: Embodiments for dynamically mitigating speculation vulnerabilities are disclosed. In an embodiment, an apparatus includes decode circuitry and branch circuitry coupled to the decode circuitry. The decode circuitry is to decode a branch hardening instruction to mitigate vulnerability to a speculative execution attack. The branch circuitry is to be hardened in response to the branch hardening instruction.