the tl;dr on that exploit (which is novel research) is that AMD fucked up and made the memory controller configuration registers unprivileged (at the platform level, which exists in rings below 0), so you can just reprogram them from ring 0.
this is, needless to say, a phenomenal fuckup on AMD's side, but does not need 10,000 words of AI slop to explain.
Replying to @ariadne@social.treehouse.systems
@ariadne Why is AMD so bad at memory controllers?..
@drq @ariadne prior to 17h (Zen) cache as RAM was used and the CPU had far more control in the boot process. The PSP on the early generations with it was optional and the platform could be booted without it.
Starting from Zen, cache as RAM was deprecated with the PSP getting far more control in the boot process, including having DRAM initialisation running there.
