MEMORY ACCESSOR INVALIDATION

There is provided a data processing apparatus that includes memory circuitry that provides a physical address space, which is logically divided into a plurality of memory segments and stores a plurality of accessors with associated validity indicators. Each of the accessors controls access to a region of the physical address space in dependence on at least its associated validity indicator. Tracking circuitry tracks which of the memory segments contain the accessors and invalidation circuitry responds to a request to invalidate an accessor by determining a set of equivalent accessors with reference to the tracking circuitry, and invalidating the accessor and the equivalent accessors by setting the associated validity indicator of each of the accessor and the equivalent accessors to indicate that the accessor and the equivalent accessors are invalid.