Messages in this thread | | | Date | Mon, 10 Oct 2011 08:09:27 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 07/12] perf_events: add LBR software filter support for Intel X86 |
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> wrote:
> (2011/10/07 20:21), Peter Zijlstra wrote: > > On Fri, 2011-10-07 at 13:18 +0200, Peter Zijlstra wrote: > >>> Yeah, depending on the depth of the LBR. But then what happens, you > >>> decode an instruction that is not what was executed. > >> > >> Right, and Andi's concern is that this might cause our instruction > >> decoder to blow up, or worse. > > > > That is, we have a fair confidence that its capable of correctly > > decoding correct streams, but I understood from Masami that they haven't > > actually tried feeding it crap. > > OK, I'll do hardening it.
Yes, that's a good idea. Could you perhaps add it to the existing build time sanity test we do for the instruction decoder, to feed it a sequence of /dev/urandom input or such?
Thanks,
Ingo
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