From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78EC61FBC for ; Wed, 20 Jul 2022 05:44:44 +0000 (UTC) Received: from zn.tnic (p200300ea97297623329c23fffea6a903.dip0.t-ipconnect.de [IPv6:2003:ea:9729:7623:329c:23ff:fea6:a903]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 58EB21EC0441; Wed, 20 Jul 2022 07:44:35 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1658295875; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=KnJwTmrzbZQLag/zXC8r1DfsvGYW7gz9MNnMX3SapF8=; b=ZfYqD87cUp3d3RCVgQSTgRjJ+N08DElz++nUMe5bD+K3/fLnKnr7qdkX1tkfAs3ADQ8kl2 Nvg6g871wMLcTqfLbq9aGOJdqYcWvyfu5fdRsYFnnQPy1aeAfIyXEVcDWZ8aRHlRtrOjcQ IVzPH0ngUJQG0jEPQX7MEf/VuGaNFLE= Date: Wed, 20 Jul 2022 07:44:30 +0200 From: Borislav Petkov To: Marc Orr Cc: Dave Hansen , Ard Biesheuvel , Dionna Amalie Glaze , "Kirill A. Shutemov" , Peter Gonda , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Varad Gautam , Dario Faggioli , Mike Rapoport , David Hildenbrand , Marcelo Cerri , tim.gardner@canonical.com, Khalid ElMously , philip.cox@canonical.com, the arch/x86 maintainers , Linux Memory Management List , linux-coco@lists.linux.dev, linux-efi , LKML , "Yao, Jiewen" Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted memory Message-ID: References: <22d54786-bc12-ecc5-2b37-cbaa56090aa8@intel.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Tue, Jul 19, 2022 at 05:26:21PM -0700, Marc Orr wrote: > These feature tags are a mess to keep track of. Well, looking at those tags, it doesn't look like you'll stop using them anytime soon. And once all the required SNP/TDX features are part of the guest image, - including unaccepted memory - if anything, you'll have less tags. :-) > - Do we anticipate (many) more features for confidential compute in > the future that require code in both the guest FW and guest kernel? If > yes, then designing a FW-kernel feature negotiation could be useful > beyond this situation. Good question. > - Dave's suggestion to "2. Boot some intermediate thing like a > bootloader that does acceptance ..." is pretty clever! So if upstream > thinks this FW-kernel negotiation is not a good direction, maybe we > (Google) can pursue this idea to avoid introducing yet another tag on > our images. Are those tags really that nasty so that you guys are looking at upstream changes just to avoid them? Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette