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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 B38FAC4CECD for ; Tue, 17 Sep 2019 11:31:32 +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 8891721852 for ; Tue, 17 Sep 2019 11:31:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8891721852 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]:44624 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iABhj-0003zZ-Fe for qemu-devel@archiver.kernel.org; Tue, 17 Sep 2019 07:31:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55788) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iABgQ-00039S-B0 for qemu-devel@nongnu.org; Tue, 17 Sep 2019 07:30:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iABgP-000098-AT for qemu-devel@nongnu.org; Tue, 17 Sep 2019 07:30:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33394) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iABgG-0008Rg-KQ; Tue, 17 Sep 2019 07:30:00 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8F219300CB6E; Tue, 17 Sep 2019 11:29:59 +0000 (UTC) Received: from gondolin (dhcp-192-230.str.redhat.com [10.33.192.230]) by smtp.corp.redhat.com (Postfix) with ESMTP id 55D5C1001B01; Tue, 17 Sep 2019 11:29:38 +0000 (UTC) Date: Tue, 17 Sep 2019 13:29:36 +0200 From: Cornelia Huck To: Greg Kurz Message-ID: <20190917132936.7a2b9c95.cohuck@redhat.com> In-Reply-To: <156871573833.196432.7906362695920387537.stgit@bahia.lan> References: <156871562997.196432.17776290406203122029.stgit@bahia.lan> <156871573833.196432.7906362695920387537.stgit@bahia.lan> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Tue, 17 Sep 2019 11:29:59 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH 17/17] checkpatch: Warn when errp is passed to error_append_hint() 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: Fam Zheng , Peter Maydell , "Michael S. Tsirkin" , Jeff Cody , Mark Cave-Ayland , qemu-devel@nongnu.org, Michael Roth , Gerd Hoffmann , Subbaraya Sundeep , qemu-block@nongnu.org, Juan Quintela , David Hildenbrand , Markus Armbruster , Halil Pasic , Christian Borntraeger , =?UTF-8?B?TWFyYy1BbmRy?= =?UTF-8?B?w6k=?= Lureau , David Gibson , Eric Farman , "Dr. David Alan Gilbert" , Yuval Shaia , Alex Williamson , qemu-arm@nongnu.org, John Snow , Richard Henderson , Kevin Wolf , "Daniel P. =?UTF-8?B?QmVycmFuZ8Op?=" , qemu-s390x@nongnu.org, Max Reitz , qemu-ppc@nongnu.org, Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 17 Sep 2019 12:22:18 +0200 Greg Kurz wrote: > Passing errp from the argument list to error_append_hint() > isn't recommended because it may cause unwanted behaviours > when errp is equal to &error_fatal or &error_abort. > > First, error_append_hint() aborts QEMU when passed either of > those. > > Second, consider the following: > > void foo(Error **errp) > { > error_setg(errp, "foo"); > error_append_hint(errp, "Try bar\n"); > } > > error_setg() causes QEMU to exit or abort, and hints aren't > added. > > Signed-off-by: Greg Kurz > --- > scripts/checkpatch.pl | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl > index aa9a354a0e7e..17ce026282a6 100755 > --- a/scripts/checkpatch.pl > +++ b/scripts/checkpatch.pl > @@ -2902,6 +2902,10 @@ sub process { > } > } > Maybe add a comment here? # using errp is common practice, so that check should hopefully be enough > + if ($line =~ /error_append_hint\(errp/) { > + WARN("suspicious errp passed to error_append_hint()\n" . Add "(use a local error object)"? > + $herecurr); > + } > # check for non-portable libc calls that have portable alternatives in QEMU > if ($line =~ /\bffs\(/) { > ERROR("use ctz32() instead of ffs()\n" . $herecurr); >