Second Level Address Translation
Second Level Address Translation (SLAT), also known as nested paging, is a hardware-assisted virtualization technology which makes it possible to avoid the overhead associated with software-managed shadow page tables. AMD has supported SLAT through the Rapid Virtualization Indexing (RVI) technology since the introduction of its third-generation Opteron processors (code name Barcelona).
Source: Wikipedia — Second Level Address Translation (CC BY-SA 4.0)