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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 083CCC43603 for ; Sun, 8 Dec 2019 21:47:00 +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 B9CC8206D5 for ; Sun, 8 Dec 2019 21:46:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XmecZQ0P" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B9CC8206D5 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]:33624 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ie4OI-0001SI-Qy for qemu-devel@archiver.kernel.org; Sun, 08 Dec 2019 16:46:58 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51137) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ie4NY-0000uu-U4 for qemu-devel@nongnu.org; Sun, 08 Dec 2019 16:46:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ie4NU-00066w-EV for qemu-devel@nongnu.org; Sun, 08 Dec 2019 16:46:09 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:50405 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ie4NT-00060e-Eo for qemu-devel@nongnu.org; Sun, 08 Dec 2019 16:46:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1575841565; 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=GzXATSvNIt3xTXUbLkno7z+Dv2yWloNWp5D67T0jvZA=; b=XmecZQ0PGxKz2/Qk+kUBKsI5RSdR8OonRIvAMP2yVXC1uNOaz/B6xE3TdSmab7cM4/8LDc vLNzujUTvewepxo+0pCPCqYJhyxTSTHqdC9JRTZyMD668ecnOye2rVGMhRX/ufOwWjtMt/ rywl3Shi9PpxuOnat2MaPuxXN6DIIx8= 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-409-eBp9qEbhNeiMUeNfAeELkg-1; Sun, 08 Dec 2019 16:46:01 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BFC5C183B700; Sun, 8 Dec 2019 21:46:00 +0000 (UTC) Received: from localhost.localdomain (vpn2-54-53.bne.redhat.com [10.64.54.53]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 01D035D9E5; Sun, 8 Dec 2019 21:45:59 +0000 (UTC) Subject: Re: [PATCH] exec: Remove the duplicated check in parse_cpu_option() To: Greg Kurz References: <20191206063337.39764-1-gshan@redhat.com> <20191206175840.06507c32@bahia.w3ibm.bluemix.net> <20191207175101.2653e7b4@bahia.w3ibm.bluemix.net> From: Gavin Shan Message-ID: Date: Mon, 9 Dec 2019 08:45:56 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <20191207175101.2653e7b4@bahia.w3ibm.bluemix.net> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: eBp9qEbhNeiMUeNfAeELkg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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: , Reply-To: Gavin Shan Cc: qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 12/8/19 3:51 AM, Greg Kurz wrote: > On Sat, 7 Dec 2019 23:56:55 +1100 > Gavin Shan wrote: > >> On 12/7/19 3:58 AM, Greg Kurz wrote: >>> On Fri, 6 Dec 2019 17:33:37 +1100 >>> Gavin Shan wrote: >>> >>>> The @cpu_option shouldn't be NULL, otherwise assertion from g_strsplit() >>>> should be raised as below message indicates. So it's meaningless to validate >>>> @model_pices[0] in parse_cpu_option() as it shouldn't be NULL either. >>>> >>>> qemu-system-aarch64: GLib: g_strsplit: assertion 'string != NULL' failed >>>> >>>> This just removes the check and unused message. >>>> >>> >>> Hrm... the check isn't about @cpu_option being NULL. It is about filtering out >>> invalid syntaxes like: >>> >>> -cpu '' >>> >>> or >>> >>> -cpu ,some-prop >>> >> >> Greg, Thanks for your review on this trivial patch. >> >> @cpu_option[0] is NULL when we have "-cpu ''". We run into assertion raised >> by subsequent cpu_class_by_name(). However, @cpu_option[0] isn't NULL with >> something like "-cpu ,xxx", but the CPU model specific class can't be found >> at last. >> > > You're right, the case with a leading ',' is caught by the other check. > >> So the validation mostly relies on cpu_class_by_name() if I'm correct. It's >> fine to remove the check. However, it provides explicit error message, which >> isn't bad though: >> >> error_report("-cpu option cannot be empty"); >> > > It's definitely not fine to remove an error message that clearly explains > to the user what he has done wrong in favor of QEMU aborting and printing > something cryptic like: > > cpu_class_by_name: Assertion `cpu_model && cc->class_by_name' failed. > > Assertions are for bugs, not for bad command line usage. > Yes, Agree as explained previously. The explicit message is a bonus at least. So please ignore this trivial patch and sorry for the noise. >>>> Signed-off-by: Gavin Shan >>>> --- >>>> exec.c | 5 ----- >>>> 1 file changed, 5 deletions(-) >>>> >>>> diff --git a/exec.c b/exec.c >>>> index ffdb518535..3cff459e43 100644 >>>> --- a/exec.c >>>> +++ b/exec.c >>>> @@ -963,11 +963,6 @@ const char *parse_cpu_option(const char *cpu_option) >>>> const char *cpu_type; >>>> >>>> model_pieces = g_strsplit(cpu_option, ",", 2); >>>> - if (!model_pieces[0]) { >>>> - error_report("-cpu option cannot be empty"); >>>> - exit(1); >>>> - } >>>> - >>>> oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]); >>>> if (oc == NULL) { >>>> error_report("unable to find CPU model '%s'", model_pieces[0]); >>> Regards, Gavin