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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B002C43334 for ; Thu, 21 Jul 2022 17:53:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 91A3E6B0073; Thu, 21 Jul 2022 13:53:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8C99C8E0002; Thu, 21 Jul 2022 13:53:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 71D688E0001; Thu, 21 Jul 2022 13:53:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 5FDB26B0073 for ; Thu, 21 Jul 2022 13:53:06 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 13D6340A85 for ; Thu, 21 Jul 2022 17:53:05 +0000 (UTC) X-FDA: 79711853172.16.4BC393C Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf24.hostedemail.com (Postfix) with ESMTP id 3D08D180008 for ; Thu, 21 Jul 2022 17:53:04 +0000 (UTC) Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 26LHSued016858; Thu, 21 Jul 2022 17:53:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : content-type : in-reply-to : mime-version; s=corp-2022-7-12; bh=ChBOQR0zmNyo0Zf+mDHFxek1YikANissaHMnCIhmmJQ=; b=VWDL9Mqq1Y7d2d0SmU2JP8VPaXg0qQ1/LSYZ2+Szt8jH1CHmuTRy7utMJEk8VSxIoIzv 0RjZHupgN4oAvuaFMqsXR8W1SHpvW66bUh4kYTGtsb+wVgCYB1V5xYxDZ8YWWMOmJ6qR /6bp2s7sopfNGkqN86pBPctgIjKdjtzl7OFqdlcxKk2o7xVSpY/CrBr2Z3YgT/PtUe3B mJCw+5hVlbDJkyZLDF5W7/L3FkdDdtLrS9ZfhdaNbZ2Ningd1laQo4uY6FXMK5vGEu4B X/kWfH8F9s+ykg0ND5eCHGTNgGkFK4LHGqh60f0fplel2QAQePU0QprQSc2iboCtBmzC Lg== Received: from phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta02.appoci.oracle.com [147.154.114.232]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3hbnvtnc6f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 21 Jul 2022 17:53:01 +0000 Received: from pps.filterd (phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 26LHHdwC010041; Thu, 21 Jul 2022 17:53:00 GMT Received: from nam10-dm6-obe.outbound.protection.outlook.com (mail-dm6nam10lp2106.outbound.protection.outlook.com [104.47.58.106]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3hc1gjqyda-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 21 Jul 2022 17:53:00 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=fs1uq9vUKGAdTm+ycBkEnC000MFIrWV0VBORdt9RjJuuYZFloDhnmZTC29kkrEuRUPV6ulv5MlNGBCchuYC6mbz1iPCzwQ5arK23P7XM+g5qz7xcX9drVNwwZRq9cwBUg8EAkT6EmSuUClLqdf7fSlFVvEojMfFgNeF2C/+i8rwNQrQQlSwDrMwd9BrZ+IXaQiKYaFcOjy2gehih34B2Gt2UvJikq8GtYrL61iwyoDtFT3R0OK8uXNKx7riGlb2TxNE0CiySlHd0ENbz+OPtjex276G6Q/6ja/vYYDjYdDNLHzPP5xFklq5GsTmt0wUc7HyA6xkW9SJwNa4AUlLWFQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ChBOQR0zmNyo0Zf+mDHFxek1YikANissaHMnCIhmmJQ=; b=kaLxX0uSK8PSoptqr8Fo90TTYaoZ4MN1o0WVg3scqaE9+oc1z+JkyR1+EkP9gKbJSa7nL5jL73QA2j7DDV96nY6GT8mRZJQukwpuosW+D5vhRA0TIIUzvoa91ZYXRUJKqDHucjx2y+f+xYF6F2uuKniPooUOYMIhqRaPIWp81JoGvCjbYwVdG88FAUiH7oZUqqIfxDBnlDI6jLzGbSALZ2Sd3rDDZbIwAw9aYqQa9ytBe4QATiPudqmznlfmz7uk9F9HJ6+ZAHRAYn8XR2Ykwe+Uvidn7/dUy8MrxWeNx9K453fBJabhpLLLhlGU/62APuQnOoAKaNQlKEwikLmtaA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ChBOQR0zmNyo0Zf+mDHFxek1YikANissaHMnCIhmmJQ=; b=l0zp2qCVDCg3ZxV7zMO6ecImix/O4dmHkaCtvWVbKuGuNgbBXA5tBwtI2mQfWjSJngzBDDXa5UAUplLRvGcwZ9cDugcMqWgFua/zkf+dUXUT4GyLWtdBg80D7f6+Z8uo8uX/Fo2IWoWEHwT68eePQTZvrfDNkv8D9z/G8ZoLQFo= Received: from BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) by DM6PR10MB2619.namprd10.prod.outlook.com (2603:10b6:5:aa::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5438.20; Thu, 21 Jul 2022 17:52:58 +0000 Received: from BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::c1ba:c197:f81f:ec0]) by BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::c1ba:c197:f81f:ec0%4]) with mapi id 15.20.5458.019; Thu, 21 Jul 2022 17:52:58 +0000 Date: Thu, 21 Jul 2022 10:52:54 -0700 From: Mike Kravetz To: Dan Carpenter Cc: Andrew Morton , Shuah Khan , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] selftests/vm: silence uninitialized variable warning Message-ID: References: Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: MW4PR04CA0385.namprd04.prod.outlook.com (2603:10b6:303:81::30) To BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 27e17f62-3b46-4c7d-97d4-08da6b41d898 X-MS-TrafficTypeDiagnostic: DM6PR10MB2619:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BY5PR10MB4196.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(7916004)(396003)(366004)(39860400002)(376002)(346002)(136003)(38100700002)(316002)(2906002)(186003)(83380400001)(4326008)(8676002)(6486002)(44832011)(6636002)(33716001)(66946007)(26005)(6666004)(6506007)(54906003)(86362001)(53546011)(66476007)(6862004)(9686003)(6512007)(8936002)(478600001)(66556008)(5660300002)(41300700001)(67856001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?gi/FnXU/TTmAXQhVU/h6XpoZG5m+crJmF3045bDXIyyI312P4XTLX1beSHgJ?= =?us-ascii?Q?c8TmAl4dR9/3Lzf1u3QP8ea+BLXmvEh1jaqVjw+ndvP0otAmH2RniU8wE281?= =?us-ascii?Q?Gj7N5scnh8NwJEWN1uSQdSSNdEmObpLCMI7xMx1zJzS8nwuv3rm4Fb5n5J26?= =?us-ascii?Q?ews/kwoP+D5OQljTbeIV3q9lWK6RO1AV65xw4pYik17+HyctBbwK5t7pskAv?= =?us-ascii?Q?ry/i+yqIvB08lyg/YqORegDjpxNMF5a74lCIJsGe35VaF6qypbuyzt9BS/k6?= =?us-ascii?Q?G0MF+PJ5nhUMx0Y+qpUnQBpXAtklSP7Up7ZlJzPWvDo6JXITqKjIVM4oYo2x?= =?us-ascii?Q?y+spAWxrq1vkqf647GdNqI+gk+KzP6vKun6VzN1lX/QC+1Kmf65TH1oAcy9K?= =?us-ascii?Q?ocxitpJtslh80cdo8W4EVi2DWXjFRbhxNbkMVTvLRhtDdphQCGXwHO3PxP2v?= =?us-ascii?Q?/+Uzrt/EKM9vyx9jXCZtY7Fa19o58kEiWNG3/Gn2DikzWPw6aQii9aJdG797?= =?us-ascii?Q?eISOEk6zEIuS1UuAOWVC/2PoFPGzTFhhorE/hWMI4FuxoawvcU7AQh0rAk/Y?= =?us-ascii?Q?ugOelXtWLYu3TrhPCy7f3sqIXiauXJtXbYYELa9gqwBB6hl4NTkRDS+4kp8X?= =?us-ascii?Q?HLbwi4qJpX95YxrOWQ2q/0CoMoSc230huri+6VhN6V/w0wfO+alvzC1eG6EK?= =?us-ascii?Q?ZLrMLZYT6q4Zt+u4mpDPjyGa3cySiGum0n+rt6fZ5lzUFwJconK1Q08YnvM8?= =?us-ascii?Q?z1d7Bk8O3e2cQytNDNyvV65wiJRDNPCIaZ2a5W/Os6ajMan7tN375+PHCqvL?= =?us-ascii?Q?RxGna5kHwSHcd/81WLC+oWmYY7hkTsQk+Q0cyyqkVHNGIXR/SKvVL1pm1lMp?= =?us-ascii?Q?OdvVnCH946C5NVdbvNBPSBUwFB8drGhmKlff8gDMQSDlUnm/2gwif4FJMy8W?= =?us-ascii?Q?4A0EXySHpnZ4X1md79UcxeoE1i7OYtTuAgEILwQ9djLFFQIal0jLYLwoqbhE?= =?us-ascii?Q?NCv7iLHKwFsIox8oVlDDcgP6ZRFu9+mhZpfS5yhg/fUp/wy5sTVTMf0lhzoJ?= =?us-ascii?Q?OfNM8em6CSzr6lwCzGUwWm+aMq1xbM+4jbWEV41G9+8M8VbMsW0bcWZ5rqKR?= =?us-ascii?Q?k1zH96n+UtkuK720bG//f036P2rHEWfp12BqSeHUzgxVdgG803vx8GNAEO4n?= =?us-ascii?Q?SZT1fmrJR34YHeXGS0rRwuWmuxpL4XXGKSKlhbNg0wq1yiT7MAyohc3s2NwW?= =?us-ascii?Q?CAVrZx46BUOMa3WVBxdqim3CoUgtmDDEDLpWYe/24b3EGTgNMzeOFjQhluMq?= =?us-ascii?Q?wuIsOu6p+JKMmzu2HQD3NeMDUiFEn5gsuxTYzEEZFHHAIqmUn+RUhlC2cJHu?= =?us-ascii?Q?LTaaD68+3RHsUnLpQw3RF8/TKhUrjv/Fd4Yopuv+hdpdHX3kpgtSYfJcVbK1?= =?us-ascii?Q?YC8umdUhG5iPL5D6Afw+PHcHocrXBaxA7moV2BiIZkerIFzMLumNWQnFlL3L?= =?us-ascii?Q?3zl/eMW4Lpqn58ifLlXTfzZmjxMr24zj26CYgwZ+F900naWaK+tyZGUCxcYP?= =?us-ascii?Q?LEGZm76UejzRrm/KVBBDMb9XMs8QY2dGaBI7OtNCjw9OHTD0RI97SfyCNkmC?= =?us-ascii?Q?HQ=3D=3D?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 27e17f62-3b46-4c7d-97d4-08da6b41d898 X-MS-Exchange-CrossTenant-AuthSource: BY5PR10MB4196.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jul 2022 17:52:57.9302 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: KMmgIUGzRSBbnvB58lcb29jfC8Fot+GkoMpP0XE4XIvn0O271/YWwfAhJLuV9vP1D9mz67c3jgpchJUzHGU7GQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR10MB2619 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-07-21_24,2022-07-21_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 spamscore=0 bulkscore=0 malwarescore=0 adultscore=0 mlxscore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2206140000 definitions=main-2207210071 X-Proofpoint-GUID: OEMuqvhNm_AR0lqTG9UfZfsIqO7MEVdt X-Proofpoint-ORIG-GUID: OEMuqvhNm_AR0lqTG9UfZfsIqO7MEVdt ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1658425985; a=rsa-sha256; cv=pass; b=wxq3MYR8eCN/ktSfG9ESoHkyb6h14KayDACdjovVUV0W0OeBGNI1KsLbtPzZnP+na4wGeY f8M7Ihy7MVxeQmfkSP6fpXrhxUnZ0C/MJ2FcsTrnUG20R1E+OCfgYDtBxxloLKof0xih6c PHmotC4Bbaqx5ops7C3ZNrk/yLvpB1E= ARC-Authentication-Results: i=2; imf24.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=VWDL9Mqq; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=l0zp2qCV; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=none (imf24.hostedemail.com: domain of mike.kravetz@oracle.com has no SPF policy when checking 205.220.165.32) smtp.mailfrom=mike.kravetz@oracle.com; dmarc=pass (policy=none) header.from=oracle.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658425985; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ChBOQR0zmNyo0Zf+mDHFxek1YikANissaHMnCIhmmJQ=; b=tN9gQstq3lX01iC2bvQz8ku8LN4uLBK79oEKgLDq0hCCJCf86tLFQu5i4wJbRN+Q/VUwMp QqY9cRHawijQOwK4nsVGZoShtNNHRW4GVNBBgaApJietozF0xcDFU9rXSiZLg8cNZyyg1R ciO+PrTY6is0bEYHnmaFeittb5verwc= Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=VWDL9Mqq; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=l0zp2qCV; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=none (imf24.hostedemail.com: domain of mike.kravetz@oracle.com has no SPF policy when checking 205.220.165.32) smtp.mailfrom=mike.kravetz@oracle.com; dmarc=pass (policy=none) header.from=oracle.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 3D08D180008 X-Stat-Signature: fqoxb6993qw7xjoyhr9dksegjwmpfd4p X-Rspam-User: X-HE-Tag: 1658425984-990700 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 07/19/22 12:42, Dan Carpenter wrote: > This code just reads from memory without caring about the data itself. > However static checkers complain that "tmp" is never properly > initialized. Initialize it to zero and change the name to "dummy" to > show that we don't care about the value stored in it. > > Fixes: c4b6cb884011 ("selftests/vm: add hugetlb madvise MADV_DONTNEED MADV_REMOVE test") > Signed-off-by: Dan Carpenter > --- > tools/testing/selftests/vm/hugetlb-madvise.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) Thanks Dan! Your analysis is correct. We do not care about the value returned, and just want to trigger a read fault. Reviewed-by: Mike Kravetz > > diff --git a/tools/testing/selftests/vm/hugetlb-madvise.c b/tools/testing/selftests/vm/hugetlb-madvise.c > index 6c6af40f5747..3c9943131881 100644 > --- a/tools/testing/selftests/vm/hugetlb-madvise.c > +++ b/tools/testing/selftests/vm/hugetlb-madvise.c > @@ -89,10 +89,11 @@ void write_fault_pages(void *addr, unsigned long nr_pages) > > void read_fault_pages(void *addr, unsigned long nr_pages) > { > - unsigned long i, tmp; > + unsigned long dummy = 0; > + unsigned long i; > > for (i = 0; i < nr_pages; i++) > - tmp += *((unsigned long *)(addr + (i * huge_page_size))); When I originally wrote this, something must have complained if written as: tmp = *((unsigned long *)(addr + (i * huge_page_size))); changing to += eliminated that complaint, but caused this one. Happy with your changes, but if there is an even better way to write this, I am happy to change it. -- Mike Kravetz > + dummy += *((unsigned long *)(addr + (i * huge_page_size))); > } > > int main(int argc, char **argv) > -- > 2.35.1 >