AMD's SEV & SME

[dm17]

Seems like these AMD security features are great. They're only available on Ryzen "PRO" and EPYC CPUs - and I'm unsure how much of their implementation is on PROs vs the seemingly more full-featured EPYC.

Anyway, I'm curious about the pros & cons here. It doesn't seem like you can disable the PSP and still have these security features. On one hand, the PSP could be a backdoor. On the other hand, not having encrypted registers & memory can be very security-enhancing.
Thoughts? Any research in this area?
Thanks a lot!