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Date:   Wed, 2 Feb 2022 08:45:34 +0000
From:   Matthew Garrett <mjg59@srcf.ucam.org>
To:     Gerd Hoffmann <kraxel@redhat.com>
Cc:     Ard Biesheuvel <ardb@kernel.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        James Bottomley <jejb@linux.ibm.com>,
        Dov Murik <dovmurik@linux.ibm.com>,
        linux-efi <linux-efi@vger.kernel.org>,
        Borislav Petkov <bp@suse.de>,
        Ashish Kalra <ashish.kalra@amd.com>,
        Brijesh Singh <brijesh.singh@amd.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Andi Kleen <ak@linux.intel.com>,
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        Dave Hansen <dave.hansen@intel.com>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Lenny Szubowicz <lszubowi@redhat.com>,
        Peter Gonda <pgonda@google.com>,
        Tobin Feldman-Fitzthum <tobin@linux.ibm.com>,
        Jim Cadden <jcadden@ibm.com>,
        Daniele Buono <dbuono@linux.vnet.ibm.com>,
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        <linuxppc-dev@lists.ozlabs.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Daniel Axtens <dja@axtens.net>
Subject: Re: [PATCH v7 0/5] Allow guest access to EFI confidential computing
 secret area
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On Wed, Feb 02, 2022 at 09:36:53AM +0100, Gerd Hoffmann wrote:

> Having a "secrets/" directory looks good to me.  Then the individual
> implementations can either add files to the directory, i.e. efi_secrets
> would create "secrets/<guid>" files.  Or each implementation creates a
> subdirectory with the secrets, i.e. "secrets/coco/" and
> "secrets/coco/<guid>".

I prefer a subdirectory, on the basis that we could conceivably end up 
with more than one implementation on a single device at some point, and 
also because it makes it trivial for userland to determine what the 
source is which may make a semantic difference under certain 
circumstances.
 
> Longer-term (i.e once we have more than one implementation) we probably
> need a separate module which owns and manages the "secrets/" directory,
> and possibly provides some common helper functions too.

Agree.