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 25543CED25D for ; Tue, 18 Nov 2025 09:48:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vLIJg-00045N-1V; Tue, 18 Nov 2025 04:48:04 -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 1vLIJf-00044h-0q for qemu-devel@nongnu.org; Tue, 18 Nov 2025 04:48:03 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vLIJd-00023b-9M for qemu-devel@nongnu.org; Tue, 18 Nov 2025 04:48:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1763459279; 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=roZ15f14m9G8k0TFcYERjC7X9OBXOAKNRBgASbBw9uk=; b=PQkZeVCq57dQ+tur8fPeCNzSLTex7cJkYR2b58+e14ly4Dod/JNbWBOAm0I8hKUfG8h5+i 1HLmVmTZYpaR980Q/A05aQFHcgqTdtz3W/wF6j5L7SwThAHkIxtZDSi5V5SV0HCmfIMFDj wHuMp+wPk4Ej0pEMhhrD6iH3P1fyDio= Received: from mx-prod-mc-03.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-612-590m-RKcPq6OqeKnuN0-7w-1; Tue, 18 Nov 2025 04:47:56 -0500 X-MC-Unique: 590m-RKcPq6OqeKnuN0-7w-1 X-Mimecast-MFC-AGG-ID: 590m-RKcPq6OqeKnuN0-7w_1763459275 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0B4B318D95C7; Tue, 18 Nov 2025 09:47:55 +0000 (UTC) Received: from redhat.com (unknown [10.44.32.26]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5E8D518004A3; Tue, 18 Nov 2025 09:47:51 +0000 (UTC) Date: Tue, 18 Nov 2025 10:47:49 +0100 From: Kevin Wolf To: Vladimir Sementsov-Ogievskiy Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, pbonzini@redhat.com, armbru@redhat.com, eblake@redhat.com, hreitz@redhat.com Subject: Re: [PATCH v9 4/7] qapi: add blockdev-replace command Message-ID: References: <20240626115350.405778-1-vsementsov@yandex-team.ru> <20240626115350.405778-5-vsementsov@yandex-team.ru> <992e1551-6d75-441f-af6e-5df9e6c85c31@yandex-team.ru> <256e998c-c0bd-40b4-94bf-de25ac9c1b02@yandex-team.ru> <4b8cade1-ecd3-4fa7-9082-7f2f1ef0b8a9@yandex-team.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4b8cade1-ecd3-4fa7-9082-7f2f1ef0b8a9@yandex-team.ru> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Am 18.11.2025 um 08:37 hat Vladimir Sementsov-Ogievskiy geschrieben: > On 17.11.25 13:49, Kevin Wolf wrote: > > Hi Vladimir, > > > > I remembered this series and wanted to check what the current status is, > > because I seemed to remember that the next step was that you would send > > a new version. But reading it again, you're probably waiting for more > > input? Let's try to get this finished. > > I think yes, I was waiting, but then switched to other tasks. > > > > > Am 02.04.2025 um 15:05 hat Vladimir Sementsov-Ogievskiy geschrieben: > > > On 18.10.24 16:59, Kevin Wolf wrote: > > > > If we want to get rid of the union, I think the best course of action > > > > would unifying the namespaces (so that nodes, exports and devices can't > > > > share the same ID) and then we could just accept a universal 'id' along > > > > with 'child'. > > > > > > Maybe we can go this way even without explicit restriction (which > > > should some how go through deprecation period, etc), but simply look > > > for the id among nodes, devices and exports and if found more than one > > > parent - fail. > > > > > > And we document, that id should not be ambiguous, should not match more > > > than one parent object. So, those who want to use new command will care > > > to make unique ids. > > > > I don't think such a state is very pretty, but it would be okay for me > > as an intermediate state while we go through a deprecation period to > > restrict IDs accordingly. > > > > So we could start with blockdev-replace returning an error on ambiguous > > IDs and at the same time deprecate them, and only later we would make > > creating nodes/devices/exports with the same ID an error. > > > > Hmm, the only question remains, is what/how to deprecate exactly? > > We want to deprecate user's possibility to set intersecting > IDs for exports / devices / block-nodes? I think, we don't > have a QAPI-native way to deprecate such thing.. We don't have to be able to express every deprecation in the schema. If it can be expressed, that's nice, but docs/about/deprecated.rst is the important part. > May be, add new "uuid" parameter, and deprecate its absence (I doubt > that we can do such deprecation too). And deprecate old IDs? But we > can't deprecate QOM path for this.. I don't think renaming options is necessary. > Hmm, or move to QOM paths for block-nodes and exports? And deprecate > export names and node names? That would only make sense if we converted the block layer to a QOM class hierarchy, which would be a project of its own. > Or we can just deprecate intersecting IDs in documentation and start > to print warning, when user make intersecting IDs? But nobody reads > warnings.. > > Is there a proper way to deprecate such things? The latter is what I would suggest. docs/about/deprecated.rst and printing warnings. I think libvirt already keeps all IDs distinct anyway, so for a large part of users nothing will change. Kevin