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From: Kevin Loughlin <kevinloughlin@google.com>
Date: Fri, 8 Mar 2024 15:52:14 -0500
Message-ID: <CAGdbjm+RMy6M=_PRg_L70g+EZ1FXi0BVub60KT4-GHuv6wLa2Q@mail.gmail.com>
Subject: Re: [PATCH v2] x86/kernel: skip ROM range scans and validation for
 SEV-SNP guests
To: Borislav Petkov <bp@alien8.de>
Cc: Ard Biesheuvel <ardb@kernel.org>, acdunlap@google.com, 
	alexander.shishkin@linux.intel.com, andrisaar@google.com, bhe@redhat.com, 
	brijesh.singh@amd.com, dave.hansen@linux.intel.com, dionnaglaze@google.com, 
	grobler@google.com, hpa@zytor.com, jacobhxu@google.com, jpoimboe@kernel.org, 
	kai.huang@intel.com, linux-kernel@vger.kernel.org, michael.roth@amd.com, 
	mingo@redhat.com, peterz@infradead.org, pgonda@google.com, 
	ross.lagerwall@citrix.com, sidtelang@google.com, tglx@linutronix.de, 
	thomas.lendacky@amd.com, x86@kernel.org, ytcoode@gmail.com
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On Fri, Mar 8, 2024 at 6:01=E2=80=AFAM Borislav Petkov <bp@alien8.de> wrote=
:
>
> On Fri, Mar 08, 2024 at 11:30:50AM +0100, Ard Biesheuvel wrote:
> > Agree with the analysis and the conclusion. However, this will need to
> > be split into generic and x86 specific changes, given that the DMI
> > code is shared between all architectures, and explicitly checking for
> > SEV-SNP support in generic code is not appropriate.
> >
> > So what we will need is:
>
> I was actually thinking of:
>
>         x86_init.resources.probe_roms =3D snp_probe_roms;
>
> and snp_probe_roms() is an empty stub.
>
> Problem solved without ugly sprinkling of checks everywhere.

Agreed, this is nicer; we can just add dmi_setup to x86_init as well
to implement the same concept for all checks we need.