All You Ever Wanted to Know about the AMD Platform Security Processor and were Afraid to Emulate...

MDs Zen (and later) CPUs contain the "(Platform) Secure Processor" (PSP) which is an embedded ARM core inside your x86 CPU responsible for initial system bootstrapping. The PSP is running even before the main x86 cores and has full access to the main memory. During system runtime it serves as a trust anchor for features like AMDs "Secure Encrypted Virtualization" feature and recently a generic TEE interface for which there are Linux kernel patches pending currently. The firmware running on the PSP is completely proprietary and there is almost no public documentation available. These are more than enough reasons for us to have a closer look at this system.

By Robert Buhren and Alexander Eichner

Full Abstract & Presentation Materials: https://www.blackhat.com/us-20/briefi...