Only if you define it to be something dumb like an error or returning 0. It should instead be defined as the hardware behavior: a load to the resulting linearly

Only if you define it to be something dumb like an error or returning 0. It should instead be defined as the hardware behavior: a load to the resulting linearly-calculated address which enters an implementation-defined exceptional state (e.g. SIGSEGV/SIGBUS) if that address does not represent readable memory.