From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EA244D3B9A2 for ; Tue, 26 Nov 2024 15:19:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tFxKb-0002lz-Rh; Tue, 26 Nov 2024 10:18:25 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tFxKZ-0002fi-RG for qemu-devel@nongnu.org; Tue, 26 Nov 2024 10:18:24 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tFxKX-0004bw-Kr for qemu-devel@nongnu.org; Tue, 26 Nov 2024 10:18:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1732634299; h=from:from:reply-to: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nUFj0u4xUrZUnxNbS5AT2u7yQ1rYvddwlqDbureuip8=; b=NoxDUscbjOz356mDw5fBlcOiu7H8j6dQPwasmcyR1IIxnpZ4aiv3NaLFHEmLY7hsIBG/CE BF3OOR4/HQPdbs7VwSqXZdjmYHnl4N8HF3ieSYwQT2hsfr8Jn2Thd9nD2R0ROznSwqIttz tIgs26NBpIgRCQXRs/NHtueGxP/yrPs= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-387-f2WajsY8OlGMqIdTKpdiDA-1; Tue, 26 Nov 2024 10:18:10 -0500 X-MC-Unique: f2WajsY8OlGMqIdTKpdiDA-1 X-Mimecast-MFC-AGG-ID: f2WajsY8OlGMqIdTKpdiDA Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E781B19775F7; Tue, 26 Nov 2024 15:17:52 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.147]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7C109300019E; Tue, 26 Nov 2024 15:17:49 +0000 (UTC) Date: Tue, 26 Nov 2024 15:17:45 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Markus Armbruster Cc: Jean-Philippe Brucker , peter.maydell@linaro.org, richard.henderson@linaro.org, philmd@linaro.org, qemu-arm@nongnu.org, qemu-devel@nongnu.org, alex.bennee@linaro.org, Eric Blake , Eduardo Habkost Subject: Re: [PATCH v3 11/26] target/arm/kvm-rme: Add measurement algorithm property Message-ID: References: <20241125195626.856992-2-jean-philippe@linaro.org> <20241125195626.856992-13-jean-philippe@linaro.org> <87ed2yowrs.fsf@pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87ed2yowrs.fsf@pond.sub.org> User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.931, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Nov 26, 2024 at 04:11:19PM +0100, Markus Armbruster wrote: > Daniel P. Berrangé writes: > > > On Mon, Nov 25, 2024 at 07:56:10PM +0000, Jean-Philippe Brucker wrote: > > [...] > > >> diff --git a/qapi/qom.json b/qapi/qom.json > >> index f982850bca..901ba67634 100644 > >> --- a/qapi/qom.json > >> +++ b/qapi/qom.json > >> @@ -1068,6 +1068,20 @@ > >> 'data': { '*cpu-affinity': ['uint16'], > >> '*node-affinity': ['uint16'] } } > >> > >> +## > >> +# @RmeGuestMeasurementAlgorithm: > >> +# > >> +# @sha256: Use the SHA256 algorithm > >> +# > >> +# @sha512: Use the SHA512 algorithm > >> +# > >> +# Algorithm to use for realm measurements > >> +# > >> +# Since: 9.3 > >> +## > >> +{ 'enum': 'RmeGuestMeasurementAlgorithm', > >> + 'data': ['sha256', 'sha512'] } > > > > > > A design question for Markus.... > > > > > > We have a "QCryptoHashAlg" enum that covers both of these strings > > and more besides. > > > > We have a choice of using a dedicated enum strictly limited to > > just what RME needs, vs using the common enum type, but rejecting > > unsupported algorithms at runtime. Do we prefer duplication for > > improve specificity, or removal of duplication ? > > With a dedicated enum, introspection shows precisely the accepted > values. > > If we reuse a wider enum, introspection shows additional, invalid > values. > > Say we later make one of these valid here. If we reuse the wider enum > now, nothing changes in introspection then, i.e. introspection cannot > tell us whether this particular QEMU supports this additional algorithm. > With a dedicated enum, it can. Whether that's needed in practice I find > hard to predict. > > I lean towards lean towards dedicated enum. > > Questions? That's fine with me. Lets stick with the approach in this patch. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|