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Date:   Thu, 23 Mar 2023 10:53:58 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Joerg Roedel <joro@8bytes.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        X86 ML <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] x86/sev: Get rid of special sev_es_enable_key
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On Thu, Mar 23, 2023 at 10:17:15AM +0100, Thomas Gleixner wrote:
> That's not sufficient. This function invokes static functions which the
> compiler can rightfully put out of line resulting in a noinstr violation.

Right, as mentioned on IRC, if we're going to use the cc_platform_has()
thing to do simple arch-agnostic confidential guests checks, perhaps we
should make it and the underlying functions it calls simply
__always_inline so that the compiler can optimize stuff even more and
not have function calls for such simple tests...

-- 
Regards/Gruss,
    Boris.

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