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Date: Mon, 4 Mar 2024 11:19:51 -0800
From: Dan Williams <dan.j.williams@intel.com>
To: Lukas Wunner <lukas@wunner.de>, Dan Williams <dan.j.williams@intel.com>
CC: Bjorn Helgaas <helgaas@kernel.org>, David Howells <dhowells@redhat.com>,
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	Alexander Graf <graf@amazon.com>
Subject: Re: [PATCH 03/12] X.509: Move certificate length retrieval into new
 helper
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References: <cover.1695921656.git.lukas@wunner.de>
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Lukas Wunner wrote:
> On Fri, Oct 06, 2023 at 12:15:13PM -0700, Dan Williams wrote:
> > Lukas Wunner wrote:
> > > The upcoming in-kernel SPDM library (Security Protocol and Data Model,
> > > https://www.dmtf.org/dsp/DSP0274) needs to retrieve the length from
> > > ASN.1 DER-encoded X.509 certificates.
> > > 
> > > Such code already exists in x509_load_certificate_list(), so move it
> > > into a new helper for reuse by SPDM.
> [...]
> > > +EXPORT_SYMBOL_GPL(x509_get_certificate_length);
> > 
> > Given CONFIG_PCI is a bool, is the export needed? Maybe save this export
> > until the modular consumer arrives, or identify the modular consumer in the
> > changelog?
> 
> The x509_get_certificate_length() helper introduced by this patch
> isn't needed directly by the PCI core, but by the SPDM library.
> 
> The SPDM library is tristate and is selected by CONFIG_PCI_CMA,
> which is indeed bool.
> 
> However SCSI and ATA (both tristate) have explicitly expressed an
> interest to use the SPDM library.
> 
> If I drop the export, I'd have to declare the SPDM library bool.
> 
> I'm leaning towards keeping the SPDM library tristate (and keep the
> export) to accommodate SCSI, ATA and possibly others.
> 
> Please let me know if you disagree.

Oh, missed that the SPDM library is the first modular consumer. Looks
good to me.