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 60931E80A89 for ; Wed, 27 Sep 2023 05:31:55 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qlN8U-0001dE-9h; Wed, 27 Sep 2023 01:30:58 -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 1qlN8S-0001d1-0H for qemu-devel@nongnu.org; Wed, 27 Sep 2023 01:30:56 -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 1qlN8K-0000IV-QG for qemu-devel@nongnu.org; Wed, 27 Sep 2023 01:30:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695792646; 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=cQ7MIivvNUbyuByh8B9uty5J+S/c6h8l+GUGjzSoxrM=; b=iPPApP9MeB7PW1cDm75qah8Mp4VCk2kkA1Jnn3y3xqAof20fX/caPYRnuWiynYHrsoFjCn ynGMCg5zTKGY/TUNbRpj6jM2/aY7TUVzmriRPRVEc17/BDY6SR4raFjhueqedbm++4qiOS TCV4DQsk/4YJBV14ibIUkn5JqxIaWgc= 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-475-EAAHiieXOxaBySweM3FgLQ-1; Wed, 27 Sep 2023 01:30:44 -0400 X-MC-Unique: EAAHiieXOxaBySweM3FgLQ-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 7DB3F28EA702; Wed, 27 Sep 2023 05:30:43 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.25]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 511542026D4B; Wed, 27 Sep 2023 05:30:43 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 3FC7E21E6900; Wed, 27 Sep 2023 07:30:42 +0200 (CEST) From: Markus Armbruster To: "Zhijian Li (Fujitsu)" Cc: "qemu-devel@nongnu.org" , "quintela@redhat.com" , "peterx@redhat.com" , "leobras@redhat.com" Subject: Re: [PATCH 50/52] migration/rdma: Silence qemu_rdma_cleanup() References: <20230918144206.560120-1-armbru@redhat.com> <20230918144206.560120-51-armbru@redhat.com> <2f697774-aea3-6f09-e781-cc1634021933@fujitsu.com> <87y1gt40dy.fsf@pond.sub.org> <31bc784d-48d5-9baa-75fb-371e73563383@fujitsu.com> Date: Wed, 27 Sep 2023 07:30:42 +0200 In-Reply-To: <31bc784d-48d5-9baa-75fb-371e73563383@fujitsu.com> (Zhijian Li's message of "Wed, 27 Sep 2023 01:41:45 +0000") Message-ID: <87cyy4gp31.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no 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 "Zhijian Li (Fujitsu)" writes: > On 26/09/2023 19:52, Markus Armbruster wrote: >> "Zhijian Li (Fujitsu)" writes: >> >>> On 18/09/2023 22:42, Markus Armbruster wrote: >>>> Functions that use an Error **errp parameter to return errors should >>>> not also report them to the user, because reporting is the caller's >>>> job. When the caller does, the error is reported twice. When it >>>> doesn't (because it recovered from the error), there is no error to >>>> report, i.e. the report is bogus. >>>> >>>> qemu_rdma_source_init(), qemu_rdma_connect(), >>>> rdma_start_incoming_migration(), and rdma_start_outgoing_migration() >>>> violate this principle: they call error_report() via >>>> qemu_rdma_cleanup(). >>>> >>>> Moreover, qemu_rdma_cleanup() can't fail. It is called on error >>>> paths, and QIOChannel close and finalization. Are the conditions it >>>> reports really errors? I doubt it. >>> >>> I'm not very sure, it's fine if it's call from the error path. but when >>> the caller is migration_cancle from HMP/QMP, shall we report something more >>> though we know QEMU can recover. >>> >>> maybe change to warning etc... >> >> The part I'm sure about is that reporting an error to the user is wrong >> when we actually recover from the error. Which qemu_rdma_cleanup() >> does. > > Yes, i have no doubt about this. > > >> >> I'm not sure whether the (complicated!) condition that triggers >> qemu_rdma_cleanup()'s ill-advised error report needs to be reported in >> some other form. The remainder of the function ignores failure... >> >> If you think we should to downgrade the error to a warning, and no >> maintainer disagrees, then I'll downgrade. Do you? > > Yes, I'd like downgrade error to a warning. Got it, thanks!