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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 288BBC433DB for ; Wed, 24 Feb 2021 15:22:01 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 81C9E64EC9 for ; Wed, 24 Feb 2021 15:22:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81C9E64EC9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:38312 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lEvzD-0000DV-G0 for qemu-devel@archiver.kernel.org; Wed, 24 Feb 2021 10:21:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:55494) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lEvhD-0007J5-Ly for qemu-devel@nongnu.org; Wed, 24 Feb 2021 10:03:24 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:53884) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lEvhB-0002IA-KR for qemu-devel@nongnu.org; Wed, 24 Feb 2021 10:03:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614179000; 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=15I/vj4yza4MCbtAnZX6zM5YZMkdCQ75JiyPSPYPD2c=; b=IuEIXu51yiMw33HuUVeA3s3LEm3hg99Hv9BTcmmFL3cYlt2qutGmdEM5CDLilVWti8bcXY sEWkRA4iG83WTOXVuQglvpG4DhuU9l23361ci6C5/kdwQeQcngEDl9zk3RqXA3Hqq/3PsU rAPPrlEowXW+QnbTW/9Y6X8OURdKOoQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-347-51KfG7W5NZ65OoS2JGbGwg-1; Wed, 24 Feb 2021 10:03:16 -0500 X-MC-Unique: 51KfG7W5NZ65OoS2JGbGwg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 40BA0131BBF2; Wed, 24 Feb 2021 14:36:23 +0000 (UTC) Received: from merkur.fritz.box (ovpn-114-142.ams2.redhat.com [10.36.114.142]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C8ED45D6D3; Wed, 24 Feb 2021 14:36:21 +0000 (UTC) Date: Wed, 24 Feb 2021 15:36:20 +0100 From: Kevin Wolf To: Stefano Garzarella Subject: Re: [PATCH] blockjob: report a better error message Message-ID: <20210224143620.GB11025@merkur.fritz.box> References: <20210223131150.124867-1-sgarzare@redhat.com> MIME-Version: 1.0 In-Reply-To: <20210223131150.124867-1-sgarzare@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vladimir Sementsov-Ogievskiy , John Snow , qemu-devel@nongnu.org, qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 23.02.2021 um 14:11 hat Stefano Garzarella geschrieben: > When a block job fails, we report 'strerror(-job->job.ret)' error > message, also if the job set an error object. > Let's report a better error message using 'error_get_pretty(job->job.err)'. > > If an error object was not set, strerror(-job->ret) is used as fallback, > as explained in include/qemu/job.h: > > typedef struct Job { > ... > /** > * Error object for a failed job. > * If job->ret is nonzero and an error object was not set, it will be set > * to strerror(-job->ret) during job_completed. > */ > Error *err; > } This is true, but there is a short time where job->ret is already set, but not turned into job->err yet if necessary. The latter is done in a bottom half scheduled after the former has happened. It doesn't matter for block_job_event_completed(), which is called only after both, but block_job_query() could in theory be called in this window. > Suggested-by: Kevin Wolf > Signed-off-by: Stefano Garzarella > --- > blockjob.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/blockjob.c b/blockjob.c > index f2feff051d..a696f3408d 100644 > --- a/blockjob.c > +++ b/blockjob.c > @@ -319,7 +319,8 @@ BlockJobInfo *block_job_query(BlockJob *job, Error **errp) > info->auto_finalize = job->job.auto_finalize; > info->auto_dismiss = job->job.auto_dismiss; > info->has_error = job->job.ret != 0; > - info->error = job->job.ret ? g_strdup(strerror(-job->job.ret)) : NULL; > + info->error = job->job.ret ? > + g_strdup(error_get_pretty(job->job.err)) : NULL; So I think we can't rely on job->job.err being non-NULL here. > return info; > } > > @@ -356,7 +357,7 @@ static void block_job_event_completed(Notifier *n, void *opaque) > } > > if (job->job.ret < 0) { > - msg = strerror(-job->job.ret); > + msg = error_get_pretty(job->job.err); > } > > qapi_event_send_block_job_completed(job_type(&job->job), Kevin