[tptacek]

This was fun to read; thanks. It's interesting how side channel attacks can be both assisted and complicated by new hardware; usually, advances in hardware tend to favor attackers slightly more than defenders, but even just by pushing operations below attacker measurement thresholds --- without even trying, that is --- hardware makes some side channels very hard to exploit.

If you're an HN'er reading along at home, Aciicmez' BTB timing paper (you should just be able to Google that) is very very very cool. They not only realized that you could theoretically watch the caches used by the branch predictor to build a trace from which you could recover RSA keys, but also came up with a very simple way to profile those branch predictor caches; that is, they designed a "spy process" like Osvik and Tromer did for memory caches that targeted the BTB instead.