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Date:   Wed, 2 Feb 2022 09:36:53 +0100
From:   Gerd Hoffmann <kraxel@redhat.com>
To:     Matthew Garrett <mjg59@srcf.ucam.org>
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>,
        Andrew Scull <ascull@google.com>,
        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>,
        linux-coco@lists.linux.dev, linux-security-module@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Nayna Jain <nayna@linux.ibm.com>, dougmill@linux.vnet.ibm.com,
        gcwilson@linux.ibm.com, gjoyce@ibm.com,
        "open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)" 
        <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
Message-ID: <20220202083653.p3cb4w3qdud4e33t@sirius.home.kraxel.org>
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  Hi,
 
> The only thing I personally struggle with here is whether "coco" is the 
> best name for it, and whether there are reasonable use cases that 
> wouldn't be directly related to confidential computing (eg, if the 
> firmware on a bare-metal platform had a mechanism for exposing secrets 
> to the OS based on some specific platform security state, it would seem 
> reasonable to expose it via this mechanism but it may not be what we'd 
> normally think of as Confidential Computing).
> 
> But I'd also say that while we only have one implementation currently 
> sending patches, it's fine for the code to live in that implementation 
> and then be abstracted out once we have another.

The implementation can be sorted later when a second implementation
shows up, but it'll be better if we don't have to change the naming
convention.

"coco/efi_secrets" doesn't look like a good choice to me, given that it
is rather likely we see more users for this showing up.

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>".

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.

take care,
  Gerd