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 BFC64C05027 for ; Tue, 14 Feb 2023 11:14:36 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pRtGU-0004Bm-Ja; Tue, 14 Feb 2023 06:14:26 -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 1pRtGS-000490-1v for qemu-devel@nongnu.org; Tue, 14 Feb 2023 06:14:24 -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 1pRtGQ-0000p7-E1 for qemu-devel@nongnu.org; Tue, 14 Feb 2023 06:14:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676373261; 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=O0t73WoejjRtjvFnvBJ75/pnm4kAN1KlPaj75+3UFD0=; b=K2u3rfVPegeavvV71flrrvkeY3mgKNd2Q6HwOHrluLEKiY3bbxZVgJn3jsO8A5faY+rGeJ 42I92kQs6KqK4GPWBXyVyqILdSKstg7JqsBwjIvsQUdP8VTceWlaH6JJJX8EofNrksnvmk rMmrEr9bY3DGy8tkzT0TARaHs5itDi0= 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-85-IdnOnruZMZqYENdgaWb29w-1; Tue, 14 Feb 2023 06:14:19 -0500 X-MC-Unique: IdnOnruZMZqYENdgaWb29w-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D41BC3C0252A; Tue, 14 Feb 2023 11:14:18 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.149]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C22462026D4B; Tue, 14 Feb 2023 11:14:16 +0000 (UTC) Date: Tue, 14 Feb 2023 11:14:14 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Krempa Cc: Markus Armbruster , eduardo@habkost.net, antonkuchin@yandex-team.ru, philmd@linaro.org, mst@redhat.com, "reviewer:Incompatible changes" , qemu-devel@nongnu.org, Vladimir Sementsov-Ogievskiy , den-plotnikov@yandex-team.ru, marcel.apfelbaum@gmail.com, pbonzini@redhat.com, eblake@redhat.com Subject: Re: [PATCH v4 14/16] qapi: deprecate "device" field of DEVICE_* events Message-ID: References: <20230213140103.1518173-1-vsementsov@yandex-team.ru> <20230213140103.1518173-15-vsementsov@yandex-team.ru> <87bklwoce9.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: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 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: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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=-0.001, 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 Tue, Feb 14, 2023 at 10:25:22AM +0100, Peter Krempa wrote: > On Tue, Feb 14, 2023 at 09:54:22 +0100, Markus Armbruster wrote: > > Daniel P. Berrangé writes: > > > > > On Mon, Feb 13, 2023 at 05:01:01PM +0300, Vladimir Sementsov-Ogievskiy wrote: > > >> The device field is redundant, because QOM path always include device > > >> ID when this ID exist. > > > > > > The flipside to that view is that applications configuring QEMU are > > > specifying the device ID for -device (CLI) / device_add (QMP) and > > > not the QOM path. IOW, the device ID is the more interesting field > > > than QOM path, so feels like the wrong one to be dropping. > > > > QOM path is a reliable way to identify a device. Device ID isn't: > > devices need not have one. Therefore, dropping the QOM path would be > > wrong. > > > > > Is there any real benefit to dropping this ? > > > > The device ID is a trap for the unwary: relying on it is fine until you > > run into a scenario where you have to deal with devices lacking IDs. > > Note that libvirt's code is still using the 'device' bit rather than QOM > path and the fix might not be entirely trivial although should not be > too hard. What's the documented way to construct a QOM path, given only an ID as input ? 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 :|