https://twitter.com/aionescu/status/894547724904931328
https://twitter.com/aionescu/status/894547838717366272
https://twitter.com/aionescu/status/894475252625018882
[…]What I discovered completely changed my understanding of 64-bit Long Mode semantics and challenged many assumptions I was making – pinging a few other experts, it seems they were as equally surprised as I was (even Mateusz”j00ru” Jurczyk wasn’t aware!). Throughout this blog post, you’ll see how x64 processors, even when operating in 64-bit long mode[…]
http://www.alex-ionescu.com/?p=340
See-also:
Firmware Security 