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 B1A83E6B243 for ; Fri, 1 Nov 2024 11:32:55 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1t6ptL-0008Pl-Vi; Fri, 01 Nov 2024 07:32:36 -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 1t6ptK-0008PV-4E for qemu-devel@nongnu.org; Fri, 01 Nov 2024 07:32:34 -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 1t6ptI-00070p-Ee for qemu-devel@nongnu.org; Fri, 01 Nov 2024 07:32:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1730460751; 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=D0JUC+kHTFRG6fVmvxchTBDugXpBgb1YjFJ3hv9tCo0=; b=EaGflDSFlv2Ko/tkd5LUlZDuyIlWNVG7cpVFJKGMItr36b0ahNVJLIcFQebkXSnVKemnrB d9iYQ6rWPck3SCx3RiQPZwT/9+DjiRSSMBHAZIEaAPFJLe26MphUYMzmxoAD96t66JhmP8 e1aZMtbcXJM3tNgV47HRqhNYQGYxULo= 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-392-FHgNeh5xNNO2RLOIrdA2YQ-1; Fri, 01 Nov 2024 07:32:29 -0400 X-MC-Unique: FHgNeh5xNNO2RLOIrdA2YQ-1 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (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 C410D19560AE for ; Fri, 1 Nov 2024 11:32:28 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.145]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8D1581956086; Fri, 1 Nov 2024 11:32:27 +0000 (UTC) Date: Fri, 1 Nov 2024 11:32:24 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Xu Cc: qemu-devel@nongnu.org, Paolo Bonzini Subject: Re: [RFC 3/5] convert code to object_new_dynamic() where appropriate Message-ID: References: <20241031155350.3240361-1-berrange@redhat.com> <20241031155350.3240361-4-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.34, 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_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 Thu, Oct 31, 2024 at 03:21:17PM -0400, Peter Xu wrote: > On Thu, Oct 31, 2024 at 03:53:48PM +0000, Daniel P. Berrangé wrote: > > In cases where object_new() is not being passed a static, const > > string, the caller cannot be sure what type they are instantiating. > > There is a risk that instantiation could fail, if it is an abstract > > type. > > > > Convert such cases over to use object_new_dynamic() such that they > > are forced to expect failure. In some cases failure can be easily > > propagated, but in others using &error_abort maintainers existing > > behaviour. > > > > Signed-off-by: Daniel P. Berrangé > > --- > > chardev/char.c | 5 ++++- > > hw/core/bus.c | 2 +- > > hw/core/cpu-common.c | 2 +- > > hw/core/qdev.c | 4 ++-- > > hw/i386/x86-common.c | 5 ++++- > > hw/i386/xen/xen-pvh.c | 2 +- > > hw/vfio/common.c | 6 +++++- > > hw/vfio/container.c | 6 +++++- > > qom/object_interfaces.c | 7 ++----- > > qom/qom-qmp-cmds.c | 15 +++++++++------ > > tests/unit/check-qom-interface.c | 3 ++- > > tests/unit/test-smp-parse.c | 20 ++++++++++---------- > > 12 files changed, 46 insertions(+), 31 deletions(-) > > I think we could leave the test cases alone without _dynamic(), because > they do test static types (even if they used "opaque"..), and they should > really (and forever) assert on failures.. > > IMHO we should keep _dynamic() usages small if we'd like to introduce it, > only in the paths where its failure will be properly handled. Basically, I > think we shouldn't use _dynamic() if we know it'll be error_abort.. because > that's fundamentally identical to object_new(). For the sake of other readers, here's what you already figured out from looking at patch 5... The end of this series will enforce that the argument to object_new() is a static, const string. It will become a compile error to pass a variable to object_new(), and thus all such cases need switching to object_new_dynamic(), even if they just end up passing in &error_abort in some cases. 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 :|