Re: [PATCH 07/12] perf_events: add LBR software filter support forIntel X86

[Ingo Molnar]

* Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx> 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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