One feature pertains to an apparatus that includes a memory circuit, a system memory-management unit (SMMU), and a processing circuit. The memory circuit stores an executable program associated with a client. The SMMU enforces memory access control policies for the memory circuit, and includes a plurality of micro-translation lookaside buffers (micro-TLBs), macro-TLB, and a page walker circuit. The plurality of micro-TLBs include a first micro-TLB that enforces memory access control policies for the client. The processing circuit loads memory address translations associated with the executable program into the first micro-TLB, and initiates isolation mode for the first micro-TLB causing communications between the first micro-TLB and the macro-TLB and between the first micro-TLB and the page walker circuit to be severed. The first micro-TLB continues to enforce memory access control policies for the client while in isolation mode.