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 12816E7719D for ; Fri, 10 Jan 2025 12:20:39 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tWDx9-0004y9-2d; Fri, 10 Jan 2025 07:17:27 -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 1tWDx0-0004GS-0T for qemu-devel@nongnu.org; Fri, 10 Jan 2025 07:17:19 -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 1tWDwx-00041w-AV for qemu-devel@nongnu.org; Fri, 10 Jan 2025 07:17:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1736511433; 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=G8F+cM0o0ec8FPrXFb3A/imTvNM7oVk4+RjgjDNH858=; b=bZfuG0VojKh+6XxzP9mzIT3mJdPEq1aKmULy1/ngHGrb2nuOJCL00g/Ruequw+dTtU75uC sf3hlXnNKPdMJ7Ki08g711G1xgyvQOjVMbgsobDW97V1UphzmTuMYdAC0KRD3BKtzOrO1g hqVPKU8jpQqAaDvcRXQ3mXFbeq5bRDE= Received: from mx-prod-mc-04.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-635-HH1qhlw3OH2UjBJ4HeCbbg-1; Fri, 10 Jan 2025 07:17:10 -0500 X-MC-Unique: HH1qhlw3OH2UjBJ4HeCbbg-1 X-Mimecast-MFC-AGG-ID: HH1qhlw3OH2UjBJ4HeCbbg Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (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-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 19C8A1955D80; Fri, 10 Jan 2025 12:17:07 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.82]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6DA5919560AD; Fri, 10 Jan 2025 12:17:00 +0000 (UTC) Date: Fri, 10 Jan 2025 12:16:56 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Akihiko Odaki Cc: Jason Wang , Dmitry Fleytman , Sriram Yagnaraman , "Michael S. Tsirkin" , Luigi Rizzo , Giuseppe Lettieri , Vincenzo Maffione , Andrew Melnychenko , Yuri Benditovich , Paolo Bonzini , Eduardo Habkost , Markus Armbruster , Michael Roth , Marcel Apfelbaum , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Yanan Wang , Zhao Liu , Lei Yang , qemu-devel@nongnu.org Subject: Re: [PATCH v4 2/4] qdev-properties: Accept bool for OnOffAuto Message-ID: References: <20250108-virtio-v4-0-cbf0aa04c9f9@daynix.com> <20250108-virtio-v4-2-cbf0aa04c9f9@daynix.com> <65364ac5-3d8e-4f43-a371-4661bf8b5437@daynix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <65364ac5-3d8e-4f43-a371-4661bf8b5437@daynix.com> User-Agent: Mutt/2.2.13 (2024-03-09) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 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: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.436, 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_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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 Fri, Jan 10, 2025 at 08:31:57PM +0900, Akihiko Odaki wrote: > On 2025/01/10 20:09, Daniel P. Berrangé wrote: > > On Wed, Jan 08, 2025 at 03:17:51PM +0900, Akihiko Odaki wrote: > > > Accept bool literals for OnOffAuto properties for consistency with bool > > > properties. This enables users to set the "on" or "off" value in a > > > uniform syntax without knowing whether the "auto" value is accepted. > > > This behavior is especially useful when converting an existing bool > > > property to OnOffAuto or vice versa. > > > > Again, to repeat my previous feedback, OnOffAuto is a well defined > > QAPI type - making it secretly accept other values/types behind > > the scenes which are not visible in QAPI scheme is not acceptable. > > > > Effectively this is a backdoor impl of a QAPI alternate > > > > { 'alternate': 'OnOffAutoOrBool', > > 'data': { > > 'o': 'OnOffAuto', > > 'b': 'bool' > > } > > } > > > > except this isn't permitted as the QAPI generator explicitly blocks > > use of alternate when the two branches are 'bool' and 'enum'. > > The QAPI generator specifically blocks the case where the enum contains 'on' > or 'off'. > > > > > I'm assuming this is because in the QemuOpts scenario, it cannot > > guess upfront whether the input is a bool or enum. This is unfortunate > > though, because at the JSON visitor level it is unambiguous. > > It's probably for the command line and possibly HMP. > > > > > I wonder if the QAPI generator could be relaxed in any viable way ? > It will make the interpretation of 'on' and 'off' on the command line > ambigious; it can be either of OnOffAuto or bool. The ambiguity would not neccessarily matter from a functional POV though. The consumer of an "OnOffAutoOrBool" field, would likely want to apply logic to collapse it into just "OnOffAuto". As such, whether "on" is parsed as a enum value or a bool value would have no functional difference in the end. The OnOffAutoOrBool is essentially there to just make sure we clearly express our input schema. 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 :|