Hyper-Threading

我们来看看那个人说的这段话：

I’d be really surprised if somebody is actually able to get a real-world attack on a real-world pgp key usage or similar out of it (and as to the covert channel, nobody cares). It’s a fairly interesting approach, but it’s certainly neither new nor HT-specific, or necessarily seem all that worrying in real life.(HT and modern CPU speeds just means that the covert channel is _faster_ than it has been before, since you can test the L1 at core speeds. I doubt it helps the key attack much, though, since faster in that case cuts both ways: the speed of testing the cache eviction may have gone up, but so has the speed of the operation you’re trying to follow, and you’d likely have a really hard time trying to catch things in real life).

It does show that if you want to hide key operations, you want to be careful. I don’t think HT is at fault per se.

「俺觉得只要是上万的牛机器，跑FreeBSD任何一个版本，目前来说都还不现实」「俺是觉得浪费了那个HTT，对不起银子……」

被人骗了说话还能这么理直气壮的人可真是不多见啊，服务器跑Windows XP好了，价格便宜量又足，呵呵……厂商几句话能让这么多人就相信，国内的计算机基础教育真是失败。

Colin Percival has released his paper about a complex security issue that accompany with Intel HyperThreading Technology. This has became FreeBSD Security Advisory SA-05:09.htt.

Now beastie.frontfree.net is running with HTT enabled.

I’m going on to track down the Pentium 4 HTT issue of FreeBSD. Currently I have setup a tinderbox (hengdm’s workstation because he is not here :-P and it’s the only box which supports HTT) and compiled a SMP kernel on it.