1. A system comprising: a plurality of processors; and a partition manager to allocate a first subset of the plurality of processors to a first partition, the first partition to execute first operating system software to manage the first subset of the plurality of processors as resources individually accessible to the first operating system software, the partition manager also to allocate a second subset of the plurality of processors to a second partition, the second partition to execute second operating system software to manage the second subset of processors as resources individually accessible to the second operating system software; wherein at least one of the processors includes: partitioning logic to support allocation of the first subset of processors to the first partition and the allocation of the second subset of processors to the second partition; and mode logic to switch operation of the plurality of processors between at least a first mode and a second mode, wherein the partitioning logic is configurable in the second mode, wherein the plurality of processors are to execute at least one of the first operating system software and the second operating system software, the partitioning logic not configurable in the first mode but enabled to maintain and enforce partitioning.