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Date:   Mon, 22 Aug 2022 23:36:45 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H . Peter Anvin" <hpa@zytor.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Kai Huang <kai.huang@intel.com>,
        Wander Lairson Costa <wander@redhat.com>,
        Isaku Yamahata <isaku.yamahata@gmail.com>,
        marcelo.cerri@canonical.com, tim.gardner@canonical.com,
        khalid.elmously@canonical.com, philip.cox@canonical.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v9 1/6] x86/tdx: Add TDX Guest attestation interface
 driver
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On Mon, Aug 22, 2022 at 02:19:44PM -0700, Dave Hansen wrote:
> This actually shows up to apps, though.

Blergh.

> They'll actually be opening /dev/tdx. When the other driver comes
> along, they'll all need to change to /dev/tdx-guest. That seems a bit
> unkind to those poor app developers.

So do you really wanna call the attestation driver "tdx-guest"?

But that's not really an attestation driver - there's tdx/tdx.c which is
all the guest code and there's an attestation "driver" in it.

So maybe this "attestation driver" thing is just an additional "ability"
of the tdx-guest driver.

Might wanna take out your cristal ball and think what you wanna call it
now so that it doesn't change because...

> BTW, do we consider these kernel names be part of the ABI? Seems like
> we should.

... yap, that.

If apps open this, then this is an ABI and cast in stone.

I'd say.

Which makes my initial suggestion of calling this whole guest
functionality a "tdx" driver not such a bad idea... Depends on
whether there will be a split at all or it'll continue gaining more
functionality.

Or so.

-- 
Regards/Gruss,
    Boris.

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