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Date:   Fri, 2 Dec 2022 14:55:08 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Juergen Gross <jgross@suse.com>
Cc:     "Kirill A. Shutemov" <kirill@shutemov.name>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v5 13/16] x86: decouple PAT and MTRR handling
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On Fri, Dec 02, 2022 at 06:56:47AM +0100, Juergen Gross wrote:
> Instead of X86_FEATURE_XENPV we could introduce something like
> X86_FEATURE_PAT_READONLY, which could be set for Xen PV guests and for
> TDX guests.

Until a third type comes which wants its pony to be pink and to dance.
:-\

Nah, we already have X86_FEATURE_TDX_GUEST - let's use that in
pat_bp_init() and exit there early and be done with it. This way it is
also self-documenting who can and cannot deal with that code.

Thx.

-- 
Regards/Gruss,
    Boris.

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