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 80A6DC83F1A for ; Thu, 17 Jul 2025 20:14:44 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ucUzs-0000w7-6z; Thu, 17 Jul 2025 16:14:28 -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 1ucSXi-0000Y4-6q for qemu-devel@nongnu.org; Thu, 17 Jul 2025 13:37:14 -0400 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 1ucSXf-0006S1-5Y for qemu-devel@nongnu.org; Thu, 17 Jul 2025 13:37:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1752773830; 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:in-reply-to:in-reply-to: references:references; bh=QABn+PyJ6yO1AL8f5+dUn7j/wEoCfHBb3tjHt39noew=; b=WHk4MFo6P5PHoaH0xLgiDgmia0X+w9cdmxfZYnpehIrwwrGNpEr+ffVFOF8/IhZzstwjNR oS+QqrAlKCk7niH6XQQpkya2+cbQSAW5IjiPQFJCGdSz7CpYHFNw7cEOSsB0Cccpmyvusz 5cptfxjmMePPrh7MJsN87rBjjPBygw0= Received: from mx-prod-mc-01.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-611-z6n0XaHBPHCMO21qUBMTew-1; Thu, 17 Jul 2025 13:37:06 -0400 X-MC-Unique: z6n0XaHBPHCMO21qUBMTew-1 X-Mimecast-MFC-AGG-ID: z6n0XaHBPHCMO21qUBMTew_1752773824 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-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BF023195FD06; Thu, 17 Jul 2025 17:37:03 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.171]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B2D781956089; Thu, 17 Jul 2025 17:36:55 +0000 (UTC) Date: Thu, 17 Jul 2025 18:36:52 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Arun Menon Cc: qemu-devel@nongnu.org, "Michael S. Tsirkin" , Marcel Apfelbaum , Cornelia Huck , Halil Pasic , Eric Farman , Richard Henderson , David Hildenbrand , Ilya Leoshkevich , Thomas Huth , Christian Borntraeger , Paolo Bonzini , Fam Zheng , Nicholas Piggin , Daniel Henrique Barboza , Harsh Prateek Bora , Alex Williamson , =?utf-8?Q?C=C3=A9dric?= Le Goater , Peter Xu , Fabiano Rosas , Hailiang Zhang , Steve Sistare , qemu-s390x@nongnu.org, qemu-ppc@nongnu.org, Stefan Berger , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Alex =?utf-8?Q?Benn=C3=A9e?= , Akihiko Odaki , Dmitry Osipenko , Matthew Rosato Subject: Re: [PATCH v5 22/23] migration: Add error-parameterized function variants in VMSD struct Message-ID: References: <20250717-propagate_tpm_error-v5-0-1f406f88ee65@redhat.com> <20250717-propagate_tpm_error-v5-22-1f406f88ee65@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250717-propagate_tpm_error-v5-22-1f406f88ee65@redhat.com> User-Agent: Mutt/2.2.14 (2025-02-20) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=unavailable 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, Jul 17, 2025 at 06:07:45AM +0530, Arun Menon wrote: > - We need to have good error reporting in the callbacks in > VMStateDescription struct. Specifically pre_save, post_save, > pre_load and post_load callbacks. > - It is not possible to change these functions everywhere in one > patch, therefore, we introduce a duplicate set of callbacks > with Error object passed to them. > - So, in this commit, we implement 'errp' variants of these callbacks, > introducing an explicit Error object parameter. > - This is a functional step towards transitioning the entire codebase > to the new error-parameterized functions. > - Deliberately called in mutual exclusion from their counterparts, > to prevent conflicts during the transition. > - New impls should preferentally use 'errp' variants of > these methods, and existing impls incrementally converted. > The variants without 'errp' are intended to be removed > once all usage is converted. > > Signed-off-by: Arun Menon > --- > include/migration/vmstate.h | 11 +++++++++++ > migration/vmstate.c | 36 +++++++++++++++++++++++++++++++----- > 2 files changed, 42 insertions(+), 5 deletions(-) > @@ -524,7 +542,9 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd, > if (ret) { > error_setg(errp, "Save of field %s/%s failed", > vmsd->name, field->name); > - if (vmsd->post_save) { > + if (vmsd->post_save_errp) { > + vmsd->post_save_errp(opaque, errp); We are already in an error path here, and we set 'errp' just a few lines above. If post_save_errp tries to set it too, then we're doomed. You'll need to pass an &Local_err in here, and then append it to the current error. > + } else if (vmsd->post_save) { > vmsd->post_save(opaque); > } > return ret; > @@ -552,7 +572,13 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd, > > ret = vmstate_subsection_save(f, vmsd, opaque, vmdesc, errp); Potentially set 'errp' > - if (vmsd->post_save) { > + if (vmsd->post_save_errp) { > + int ps_ret = vmsd->post_save_errp(opaque, errp); so must not be passing 'errp' here. > + if (!ret && ps_ret) { > + ret = ps_ret; > + error_prepend(errp, "post-save failed: %s ", vmsd->name); > + } > + } else if (vmsd->post_save) { > int ps_ret = vmsd->post_save(opaque); > if (!ret && ps_ret) { > ret = ps_ret; > > -- > 2.50.0 > > 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 :|