Until then, both AMD and myself both agree that this only affects the method that the Windows implementation uses. I don't think the AMD PSIRT team would misrepresent their findings too.
I wont say it will never affect the Linux PSP implementation, however the driver behaves differently.
I hate 'throwing credentials', but I do work for the Red Hat Product Security team and we have a line of communication with hardware vendors for this reason.
However, in general all sources I read say that the PSP runs some closed source firmware and it has full access to the main memory. So that will always remain a nasty source of insecurity unless there is a switch to disable it (reportedly some BIOSes have such switch, but I have not heard about any 3rd party audit what such switch does.) Vendors will always tell you that their proprietary solution is secure and does not leak any data until someone can somewhat trustworthy demonstrate that they were wrong. Experience has shown that typically it's not a question of whether it happens, but when it happens. It can take years but someday some smart person finds a way. Some create a logo and a website to earn reputation. others earn money secretly.
No, I don't have any insider information you would not have. I just believe the information that it's an ARM processor running closed firmware and it has memory access.
What causes (and avoids) it in drivers can be reproduced/bypassed elsewhere
