Date:   Mon, 13 Feb 2023 16:11:08 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Juergen Gross <jgross@suse.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        lists@nerdbynature.de, mikelley@microsoft.com,
        torvalds@linux-foundation.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v2 2/8] x86/mtrr: support setting MTRR state for software
 defined MTRRs
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On Mon, Feb 13, 2023 at 04:03:07PM +0100, Borislav Petkov wrote:
> > Wouldn't !cpu_feature_enabled(X86_FEATURE_HYPERVISOR) be enough?
> >
> > I'm not sure we won't need that for TDX guests, too.
>
> See, that's the problem. I wanna have it simple too. Lemme check with
> dhansen.

He says MTRRs are enabled in TDX guests: "X86_FEATURE_MTRR is fixed to
1 in TDX guests."

So we will have to do the more finer-grained check I guess.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette