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=-12.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 C3830C433E0 for ; Fri, 12 Feb 2021 15:54:40 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 4E45664E02 for ; Fri, 12 Feb 2021 15:54:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E45664E02 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.84349.158170 (Exim 4.92) (envelope-from ) id 1lAam8-00031e-5B; Fri, 12 Feb 2021 15:54:32 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 84349.158170; Fri, 12 Feb 2021 15:54:32 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lAam8-00031X-1w; Fri, 12 Feb 2021 15:54:32 +0000 Received: by outflank-mailman (input) for mailman id 84349; Fri, 12 Feb 2021 15:54:30 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lAam6-00031R-Ol for xen-devel@lists.xenproject.org; Fri, 12 Feb 2021 15:54:30 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 01c6bf23-4629-4233-a6a5-ab47d3435a42; Fri, 12 Feb 2021 15:54:30 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 50A45AD29; Fri, 12 Feb 2021 15:54:29 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 01c6bf23-4629-4233-a6a5-ab47d3435a42 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613145269; h=from:from:reply-to: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=C7GMDUyMOdTLI3rewXsY5zd2XTLH56wGuBSolmtWDq4=; b=klk5ZmyMZS+rwZq5oJVvqQ6K9dOpJivuQmr3cvKDL0jBd+MEPA7vZXr8On+/5F4fb9UJCz 4su0Rz2IBQSizFAt5NMU2cDFDrUCx5jdZn79DO1leJikogfvw/UCPupC5lZ9fJM2kAzbWU c8AcFfJ+WW+7IKyUpi3foeI2JlYFuZs= Subject: Re: [PATCH 02/10] tools/libxg: Fix uninitialised variable in write_x86_cpu_policy_records() To: Andrew Cooper Cc: Ian Jackson , Wei Liu , Xen-devel References: <20210212153953.4582-1-andrew.cooper3@citrix.com> <20210212153953.4582-3-andrew.cooper3@citrix.com> From: Jan Beulich Message-ID: Date: Fri, 12 Feb 2021 16:54:30 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210212153953.4582-3-andrew.cooper3@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 12.02.2021 16:39, Andrew Cooper wrote: > Various version of gcc, when compiling with -Og, complain: > > xg_sr_common_x86.c: In function 'write_x86_cpu_policy_records': > xg_sr_common_x86.c:92:12: error: 'rc' may be used uninitialized in this function [-Werror=maybe-uninitialized] > 92 | return rc; > | ^~ > > The complaint is legitimate, and can occur with unexpected behaviour of two > related hypercalls in combination with a libc which permits zero-length > malloc()s. > > Have an explicit rc = 0 on the success path, and make the MSRs record error > handling consistent with the CPUID record before it. > > Fixes: f6b2b8ec53d ("libxc/save: Write X86_{CPUID,MSR}_DATA records") > Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich