Re: [PATCH] perf/x86: check ucode before disabling PEBS on SandyBridge

Borislav Petkov
2012-06-12T17:23:33Z

On Tue, Jun 12, 2012 at 07:18:13PM +0200, Peter Zijlstra wrote:
> But the ucode loader can be (ab)used to only update one of the many
> CPUs.

Not if you don't support mixed ucode revisions. In that case, you want
the same ucode patch applied to _all_ cores on the system. Otherwise,
random freezes, explosions and other cataclysmic events can happen.

--
Regards/Gruss,
Boris.

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