Abstract: Operating system deactivation of write protection for a storage block is provided absent quiescing of processors in a multi-processor computing environment. The process includes receiving an address translation protection exception interrupt resulting from an attempted write access by a processor to a storage block, and determining by the operating system whether write protection for the storage block is active. Based on write protection for the storage block not being active, the operating system issues an instruction to clear or modify translation lookaside buffer entries of the processor associated with the storage block, absent waiting for an action by another processor of multiple processors of the computing environment, to facilitate write access to the storage block proceeding at the processor.

Abstract: An instruction is provided to perform a reset address translation protection operation when executed. Executing the instruction includes determining, by a processor, that an address translation protection bit in a specified translation table entry associated with a storage block is to be reset. Based on determining that the address translation protection bit is to be reset, executing the instruction includes resetting the address translation protection bit to deactivate write protection for the storage block. The resetting is absent waiting for an action by one or more other processors of the computing environment.

Abstract: Operating system deactivation of write protection for a storage block is provided absent quiescing of processors in a multi-processor computing environment. The process includes receiving an address translation protection exception interrupt resulting from an attempted write access by a processor to a storage block, and determining by the operating system whether write protection for the storage block is active. Based on write protection for the storage block not being active, the operating system issues an instruction to clear or modify translation lookaside buffer entries of the processor associated with the storage block, absent waiting for an action by another processor of multiple processors of the computing environment, to facilitate write access to the storage block proceeding at the processor.

Abstract: A system is provided and includes a plurality of machines. The plurality of machines includes a first generation machine and a second generation machine. Each of the plurality of machines includes a machine version. The first generation machine executes a first virtual machine and a virtual architecture level. The second generation machine executes a second virtual machine and the virtual architecture level. The virtual architecture level provides a compatibility level for a complex interruptible instruction to the first and second virtual machines. The compatibility level is architected for a lowest common denominator machine version across the plurality of machines. The compatibility level includes a lowest common denominator indicator identifying the lowest common denominator machine version.

Abstract: A system is provided and includes a plurality of machines. The plurality of machines includes a first generation machine and a second generation machine. Each of the plurality of machines includes a machine version. The first generation machine executes a first virtual machine and a virtual architecture level. The second generation machine executes a second virtual machine and the virtual architecture level. The virtual architecture level provides a compatibility level for a complex interruptible instruction to the first and second virtual machines. The compatibility level is architected for a lowest common denominator machine version across the plurality of machines. The compatibility level includes a lowest common denominator indicator identifying the lowest common denominator machine version.

Abstract: A fully testable CMOS comparator circuit is disclosed having INV and NAND logic gates which form data paths for propagating data through the comparator circuit. The data propagated through the comparator circuit include greater-or-equal signals. The comparator is fully testable because there are no redundant circuit elements.