linux-kernel - Re: [PATCH 2/2] x86: Clear incorrectly forced X86_FEATURE_LAHF

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Message-ID: <20090813155449.GA8534@aftab>
Date:	Thu, 13 Aug 2009 17:54:49 +0200
From:	Borislav Petkov <borislav.petkov@....com>
To:	Brian Gerst <brgerst@...il.com>
CC:	kjwinchester@...il.com, mikpe@...uu.se, mingo@...e.hu,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] x86: Clear incorrectly forced X86_FEATURE_LAHF_LM
 flag

On Thu, Aug 13, 2009 at 10:21:22AM -0400, Brian Gerst wrote:
> > +               /*
> > +                * Some BIOSes incorrectly force this feature, but only K8
> > +                * revision D (model = 0x14) and later actually support it.
> > +                */
> > +               if (c->x86_model < 0x14) {
> 
> Shouldn't you test that the flag is actually set before trying to clear it?

Yep, I'll do that in the final version of the patches.

-- 
Regards/Gruss,
Boris.

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