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Date: Thu, 2 Jul 2026 11:15:43 +0200
From: Ingo Molnar <mingo@kernel.org>
To: =?iso-8859-1?Q?J=FCrgen_Gro=DF?= <jgross@suse.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org,
	Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
	Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	"H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 05/32] x86/mtrr: Stop using 32-bit MSR interfaces
Message-ID: <akYsP5la7hw_pKEL@gmail.com>
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* Jürgen Groß <jgross@suse.com> wrote:

> > > alternative I could use struct msr by doing:
> > > 
> > >    rdmsrq(MSR_K6_UWCCR, msr.q);
> > >    regs[0] = msr.l;
> > >    regs[1] = msr.h;
> > > 
> > >    ...
> > > 
> > >    msr.l = regs[0];
> > >    msr.h = regs[1];
> > >    wrmsrq(MSR_K6_UWCCR, msr.q);
> 
> I think it would be easier to just use that initially. I can change the
> patch accordingly.
> 
> > Or just move regs[] over to a struct msr variable use?
> 
> That would be nasty, as the index used for addressing the correct regs[]
> member is _calculated_, so for each access there would need to be an "if".

Ok, fair enough.

Thanks,

	Ingo