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 7AB61EE7FE5 for ; Fri, 8 Sep 2023 12:27:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qeaZ4-00040B-7X; Fri, 08 Sep 2023 08:26:22 -0400 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 1qeaZ2-0003vI-Ag for qemu-devel@nongnu.org; Fri, 08 Sep 2023 08:26:20 -0400 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 1qeaYy-0007lN-Sl for qemu-devel@nongnu.org; Fri, 08 Sep 2023 08:26:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694175976; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=U5nuETMLzCmtMCNwvivllkCcNWiiVU6hf4rdBB3xRCo=; b=fByr+a1eZCLbTCMzXTJGVS46nyJR+xX0MfMbYZ7jaeAAIB5uNIozSBeRAiXJJ7WBKwi/sP IlfWfyUNQGk2b+mVGom8OgEufvJtOmP5OMX9HTWYZTQEq9B763rNpzBl42siZHSyFMXzR+ cb2zz/aKS31sKpiGgI7gK2Aa/X87Pvo= Received: from mimecast-mx02.redhat.com (mx-ext.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-542-4aMLSIQUMjWVNxvcoK9TuQ-1; Fri, 08 Sep 2023 08:26:14 -0400 X-MC-Unique: 4aMLSIQUMjWVNxvcoK9TuQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5372A3815EF2; Fri, 8 Sep 2023 12:26:14 +0000 (UTC) Received: from redhat.com (unknown [10.39.193.201]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5AE6D2026D2B; Fri, 8 Sep 2023 12:26:13 +0000 (UTC) Date: Fri, 8 Sep 2023 14:26:12 +0200 From: Kevin Wolf To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Cc: qemu-devel@nongnu.org, Markus Armbruster , Eduardo Habkost , Paolo Bonzini , Peter Maydell Subject: Re: [PATCH] hw: forbid DEFINE_PROP_ARRAY for user creatable devices Message-ID: References: <20230908092951.2683721-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230908092951.2683721-1-berrange@redhat.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 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, 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Am 08.09.2023 um 11:29 hat Daniel P. Berrangé geschrieben: > The DEFINE_PROP_ARRAY macro is a clever trick for defining array > properties. It initially creates a property "len-$FOO". When that > property is set, then it creates a sequence "$FOO[NN]" for NN > in the range 0 to "len-$FOO". > > The intended usage for this was to simplify code for internal > devices, however, it crept into use for user creatable devices > when the 'rocker' network device used it. > > This relied on the user specifying the len property first on > the -device comand line, and the args being processed in-order. > The latter was broken[1] when -device was converted from QemuOpts > to QDict[2], as ordering of loading properties was no longer > guaranteed to match user specified ordering. > > This change poisons the setter for "len-$FOO" such that it raises > an error when used with a user creatable device. > > This allows DEFINE_PROP_ARRAY to remain exclusively for internal > devices, since code can ensure properties are set in the correct > ordering. > > [1] https://gitlab.com/qemu-project/qemu/-/issues/1090 > [2] f3558b1b763683bb877f7dd5b282469cdadc65c3 > Signed-off-by: Daniel P. Berrangé NACK. This doesn't fix the problem, but breaks rocker for good. As I said, I'm working on proper array support and will send patches soon. Kevin