Abstract: A technique includes during in-service use of a memory package in a computer system, using a first interface to access a defective address memory of the memory package. The defective address memory is accessible by a manufacturer of the memory package prior to the in-service use using a second interface of the memory package other than the first interface. In connection with the in-service use of the memory package, the memory package is repair, a repair that includes storing a defective address in the defective address memory to change an address mapping for at least one cell of the storage array.

Abstract: An apparatus includes a memory module, which includes a memory array. The memory array includes rows of memory and columns of memory. The apparatus also includes at least one row of memory not in the memory array and a register. The register includes an address space and a row/column indicator. The apparatus also includes row selection logic to select the at least one row to be activated if the address from an address bus equals the register value and if the row/column indicator indicates row.