1. A method of validating operations in a logically partitioned data processing system, the method comprising the computer implemented steps of: receiving an input/output operation that includes a virtual host identifier; looking up a data structure with the virtual host identifier, wherein the data structure is associated with the virtual host and defines an address space associated with the virtual host; responsive to looking up the data structure; identifying a direct memory access address in a work queue data structure associated with the input/output operation; comparing the direct memory access address with the address space; and responsive to comparing the direct memory access address, determining if the input/output operation is valid.