From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mx.groups.io with SMTP id smtpd.web10.10348.1674028309631515610 for ; Tue, 17 Jan 2023 23:51:50 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=Si5BFPcr; spf=pass (domain: redhat.com, ip: 170.10.133.124, mailfrom: kraxel@redhat.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1674028308; 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: in-reply-to:in-reply-to:references:references; bh=wGNzJ+IktHZmNqaFlDrMhWkTURpf/0hrykEij67avpU=; b=Si5BFPcr7YgsSo3fXZIYVm1UaTcvFIkNPaTlKv5g0f8QYJXV8JR6BjqQxz3d7XqPZ/b/FZ kfV63ukJJ3ZcXT7KjzP2HGvCSju1LehW85gWHnDX78ndfSUmvMc+VEqMen1Wax/DBmAwua /ix4/3cah7R+08pI88rIlPhOn79woYw= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-422-Wibq0QIGMcKNIpc03dw2JQ-1; Wed, 18 Jan 2023 02:51:43 -0500 X-MC-Unique: Wibq0QIGMcKNIpc03dw2JQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 041CE38041C0; Wed, 18 Jan 2023 07:51:43 +0000 (UTC) Received: from sirius.home.kraxel.org (unknown [10.39.192.186]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 97CF039D92; Wed, 18 Jan 2023 07:51:42 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 025421800091; Wed, 18 Jan 2023 08:51:40 +0100 (CET) Date: Wed, 18 Jan 2023 08:51:40 +0100 From: "Gerd Hoffmann" To: devel@edk2.groups.io, dionnaglaze@google.com Cc: "Kirill A. Shutemov" , Ard Biesheuvel , "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, x86@kernel.org, jiewen.yao@intel.com, "Min M. Xu" , James Bottomley , Tom Lendacky , Erdem Aktas , Dave Hansen Subject: Re: [edk2-devel] [PATCH v2] x86/efi: Safely enable unaccepted memory in UEFI Message-ID: <20230118075140.6pyszln4ovi2htxk@sirius.home.kraxel.org> References: <20230113212926.2904735-1-dionnaglaze@google.com> <20230113222024.rp2erl54vx3grdbd@box.shutemov.name> <20230116105648.63hsxnmj2juwudmu@sirius.home.kraxel.org> <20230116123057.wvr6rz7y3ubgcm5z@box.shutemov.name> <20230116134246.soworigs56bz5v7o@box.shutemov.name> <20230116231711.cudsnxvnfg6aef3w@box.shutemov.name> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi, > To Gerd's point, removing "first in edk2, later in linux too" I think > is backwards. We need all users of the protocol to agree that SEV-SNP > and TDX strictly imply unaccepted memory support. Only then can we > remove the protocol from EDK2. Its not backwards. edk2 dropping support first would result in break kernels without support for unaccepted memory. Which is why we wait until such kernels are EOL. Linux dropping support first would result in firmware accepting all memory again. So that isn't a good plan. Thats why linux should support the protocol a bit longer, while firmware versions which expect negotiation happening are still in use. take care, Gerd