From patchwork Tue Nov 8 07:44:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 9416801 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B9E4160459 for ; Tue, 8 Nov 2016 07:47:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A8F8B289B5 for ; Tue, 8 Nov 2016 07:47:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9B593289DF; Tue, 8 Nov 2016 07:47:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 387A7289B5 for ; Tue, 8 Nov 2016 07:47:27 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c415M-0002Rw-AI; Tue, 08 Nov 2016 07:44:48 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c415L-0002Ro-46 for xen-devel@lists.xenproject.org; Tue, 08 Nov 2016 07:44:47 +0000 Received: from [85.158.137.68] by server-16.bemta-3.messagelabs.com id 21/C6-12362-E6281285; Tue, 08 Nov 2016 07:44:46 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprLIsWRWlGSWpSXmKPExsXS6fjDSze3STH CYGmblcX3LZOZHBg9Dn+4whLAGMWamZeUX5HAmvH80kvmggdsFfun/mBtYLzO2sXIySEkkCex vqOHDcTmFbCTmPPrDCOILSFgKPH0/XWgOAcHi4CqRNO9JJAwm4C6RNuz7WCtIgJxEoeuvGUHs ZkFnCU2LmtnASkXFvCVaHuVB2LyCghK/N0hDFGhJfHw1y0WCFtbYtnC18wgJcwC0hLL/3FMYO SZhdAwC0nDLCQNsxAaFjCyrGLUKE4tKkst0jW00EsqykzPKMlNzMzRNTQw1stNLS5OTE/NSUw q1kvOz93ECAykegYGxh2Mv097HmKU5GBSEuV9X6AYIcSXlJ9SmZFYnBFfVJqTWnyIUYaDQ0mC V6URKCdYlJqeWpGWmQMMaZi0BAePkghvMkiat7ggMbc4Mx0idYrRmOPNrpcPmDjebX73gEmIJ S8/L1VKnDcCpFQApDSjNA9uECzWLjHKSgnzMjIwMAjxFKQW5WaWoMq/YhTnYFQS5rUEmcKTmV cCt+8V0ClMQKdUxSiAnFKSiJCSamBcuqXut8AXrpxQzd0v78/fHy81f9Z205JpxoIhand+F98 v2HB7S+M2+832SqJWP7yu75jY92HqPg2beZKspu0PzkzYeig6d88++0quNzOyFA6t6mJIXOLk YV8y97+ks8+V2yqvrjLtcPy9hOHkwQV9rwsOrrm+88KBN/5cN6XvKh9+zbDZ96OFvxJLcUaio RZzUXEiAINuIJawAgAA X-Env-Sender: JBeulich@suse.com X-Msg-Ref: server-5.tower-31.messagelabs.com!1478591083!66497065!1 X-Originating-IP: [137.65.248.74] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.0.13; banners=-,-,- X-VirusChecked: Checked Received: (qmail 43484 invoked from network); 8 Nov 2016 07:44:45 -0000 Received: from prv-mh.provo.novell.com (HELO prv-mh.provo.novell.com) (137.65.248.74) by server-5.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 8 Nov 2016 07:44:45 -0000 Received: from INET-PRV-MTA by prv-mh.provo.novell.com with Novell_GroupWise; Tue, 08 Nov 2016 00:44:43 -0700 Message-Id: <58219077020000780011CF59@prv-mh.provo.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.2.1 Date: Tue, 08 Nov 2016 00:44:39 -0700 From: "Jan Beulich" To: ,, "Juergen Gross" Mime-Version: 1.0 Content-Disposition: inline Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org Subject: [Xen-devel] [PATCH v2] xen/manage: correct return value check on xenbus_scanf() X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP A negative return value indicates an error; in fact the function at present won't ever return zero. Signed-off-by: Jan Beulich --- v2: For consistency with other code don't consider zero an error (utilizing that xenbus_scanf() at present won't return zero). Adjust commit message accordingly. --- drivers/xen/manage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 4.9-rc4/drivers/xen/manage.c +++ 4.9-rc4-xen-manage-xenbus_scanf/drivers/xen/manage.c @@ -277,7 +277,7 @@ static void sysrq_handler(struct xenbus_ err = xenbus_transaction_start(&xbt); if (err) return; - if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) { + if (xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key) < 0) { pr_err("Unable to read sysrq code in control/sysrq\n"); xenbus_transaction_end(xbt, 1); return;