Accessing topological mapping of cores

A method, computer program product, and system include a processor(s) issues an instruction that includes processing core information that includes locations of processing cores of the computing system (logical cores and/or physical cores), and an operator selection. The processor(s) sets security parameters for information returned by the instruction which is topological information for mapping of the logical cores to the physical cores. The processor(s) obtains the topological information and utilizes an operating system to map the logical cores to the physical cores.