Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <fdec491a-5dfd-6c9c-c961-18dcd9d0b3bb@oracle.com>
Date:   Tue, 14 Jun 2022 11:33:10 +0100
Subject: Re: [PATCH] mm: Remove unwanted initialization in
 vmemmap_populate_compound_pages()
Content-Language: en-US
To:     Gautam Menghani <gautammenghani201@gmail.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        akpm@linux-foundation.org
References: <20220612182320.160651-1-gautammenghani201@gmail.com>
From:   Joao Martins <joao.m.martins@oracle.com>
In-Reply-To: <20220612182320.160651-1-gautammenghani201@gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TW82Q0dnTi95NXhiUG9rT253T0J2YVJTZkVxbUFiM1lpOUlHdmxENHNMVzFZ?=
 =?utf-8?B?QkVOMW1GYW1OaFF3c2ROQXNOQWZrSnpXdG5RL3VYNVJLa3FDMVRtcnlpcVIv?=
 =?utf-8?B?cit3YkNzZHdWdnNta1FyWkNPNDYyVWsrVDhhc083RUZFdUUrUk02L05RZ0pr?=
 =?utf-8?B?YkpUajhFMlRTa3lib1VRUGZnV1dqS1k4bHRtOTQwQ0lBeitCTmdmc2UySkZh?=
 =?utf-8?B?RnJ1YWpqWG5rMXpmWUwxWFZPTnZ2SHNaVkVLRzBzajk5OHFQSVF2K0VTU0Jy?=
 =?utf-8?B?c29QTEVsU0FyOU1DVGNPOVY2ZHhuTWk2VVQvYW1aMVQxcjJHOCtseGcrcjBU?=
 =?utf-8?B?MHV3Qi9tNldQd2FSNktObWszKy9TdytpNStFTWF2d21VcjdvUmJVcmYwRVd5?=
 =?utf-8?B?L0g1d250cW1JVloxMFlFMDdEZ3hsdFhKSEszWlY0Z0ZlVUFPdmVxT0RIQ1Rl?=
 =?utf-8?B?THZuZXBtWVNxVHdNNm1ka3FlRFJrcmNqNE5Ka2g1WEs4SzQrU2FsWHZjS1Fu?=
 =?utf-8?B?YXZQdklXcnZucDRldHdUVXh4N24rbjc5ZTUvZHI1TElyUlN1NVROUm9naHQ5?=
 =?utf-8?B?bjZQMTY2WVhUMldlbTdVeThhaHVoVEU5bmJkVWtKSXhKTGVLWmlEUEpkUE8v?=
 =?utf-8?B?bllDOGg3QnIwbG5ma3BoMHQvaXBGeStTbk0wd2tMcHdXNGZlSXoxNzR1MlFX?=
 =?utf-8?B?anNlZ0hOa0FUalhZQVNCNzBSV3NKL1h0VDMvdGk5NDAwKzJ0QitmbWhnc2Ru?=
 =?utf-8?B?WDN1eUdYMk96R2hZRWFyaElORi9HTmdxaEE0OS9JUzBRcG5SZ2JpR1JrWTA3?=
 =?utf-8?B?TnM2ZGhaSXNyMDdOQzh0bEo3SngrdUViaW56dHhnYVNnMzdITmFuNVdRRUVB?=
 =?utf-8?B?MHVqRHBTMlgvQk5xb0RBTU00QmkyYTVpeWlaU2JmTWMxbFljekhtL1FwVlN5?=
 =?utf-8?B?ZmdmYW1UUjZVeVQ0YjdYbHhrRWdpbjhCZjZlekF3YjZwejdNcTBDdUNVVC9v?=
 =?utf-8?B?SktMZ3B0NlhBaTlXN1Fic2dPN015RDB2c1kwVG5vODBKMCtIb2M4aVB0WnFs?=
 =?utf-8?B?V3FNZGd1QWptTkR1QUlpNU1wUmtKMEYxM2JJN0FoN3hDMVdQV2hWdmNtaWFp?=
 =?utf-8?B?Vllsb0g5aWVwdkduUFNncVRONmZleDhQc1lSbDFxbWlLemF4Q05HSVNpdUtq?=
 =?utf-8?B?R2tLQVpXM3RaK3ZSVHJXcUZHMXN1RjBYcDV2bXI2V2VnaEVJRnE3c2ljZFVU?=
 =?utf-8?B?Q3lnSEZxZEdxbmluM1NIaC9XYUxacm5UUjc3M2MweWhzdE0wUnltOE4wSGF0?=
 =?utf-8?B?QWNDU2Vpd2pHTG4zUGhTblMvUG1GSkRoK2g4T3ZaMU80VEhuWEkvVUtqZWgx?=
 =?utf-8?B?c2hJU2pGbzVhYm5POENOS09iYVBQazFYclpTM08xdUlKS2RVMWhOQjcwYWti?=
 =?utf-8?B?NGp5Rm5oZ01wVUFpc2ZzRU1pR09yWHFyRWJacWJLeEJGcTZDQ2g3N1pVSzU5?=
 =?utf-8?B?Qmw0RnhaVDFpRUFldzE2R1dLNEVSQm0xdWxLZDNkeE5wajRYd3V5QkZMZi9E?=
 =?utf-8?B?eUorRytacFlmQUhSTUQzeUtLNjlJMUZFTUZjQzVBMFJTcXNJeUJQeVRNd0ZX?=
 =?utf-8?B?aHo4Q2ZSNmViaVM5V2Yrb0tiL3VYdUlmQW9oZ0N2TTFZQ3lQbDErRklSYWo4?=
 =?utf-8?B?ZmpGcWtKazNUQTBsdXBHYWc0cmdzdGpsMzlXWEhLL3YveVNYeVJrTFkwN3F4?=
 =?utf-8?B?cENoUCt0T3FyS0JiWUZYejlmZFdtQlpUa08ycm1FSENKWFpxeG9uaDd3M1Bp?=
 =?utf-8?B?ZWVxai96ZDFIUXlQVk40VHlacDRzNHkrUFBObGdidlNSWFdSZkY1QjRnVXFp?=
 =?utf-8?B?Y1Ewc1NUQjVNVVExY0Ntako0d2NST2xJNnR0eEpvcHc4ZTV3cExzVXNNYk1L?=
 =?utf-8?B?ck9RRmFsOXRmOHAxZXdBVUNqdjJsb1BCbytpam5RaFVYTXRIaGZleTUyaUJu?=
 =?utf-8?B?SzF6cE1ObndnREVhdHltYU5DVlhsRDA0WGRQV1lEK2JZSWQ5dEtBc0s2eU5O?=
 =?utf-8?B?SVVWQVp1YnNiSnJoMi8yemJQMWdJTm9MSDl6UEN2eEFzcmNzRWNCVnVQSjBi?=
 =?utf-8?B?V0k1cm9sVng4SUo5TUl0Y1hZNVFWVU0zdlhDK0tFSCtUbnp6M21qRHVxWDFh?=
 =?utf-8?B?dC9pV2ZBdzRvNnpjN1M2cXUzaWpaY3VETmZENC8rRDkvcUNFa1dpajN4UFZD?=
 =?utf-8?B?SytISnh6aFVrb3RHNVI0RVVjSnVrd2Zkdkl1TEk1Tkx4NXJ0UjMyQmJDaU83?=
 =?utf-8?B?dFJ5em51SUI0dmErYnRlZkRYK1pzbk90cGxROS9aVmRnOW8xZXpWTW5JNFl1?=
 =?utf-8?Q?S1xby2Mc4KnTeOKs=3D?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: f6efb827-9731-4eae-94e4-08da4df14a1b
X-MS-Exchange-CrossTenant-AuthSource: BLAPR10MB4835.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Jun 2022 10:33:15.3843
 (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: T2elmRiKcHT3+WqXZrAv3zPqTRDB7vJlQvrSRGaQFgMElUwidFoJtDnuJF9pV+/le72NHserEDOW2oN8e++QEVo9WkMciYmzCK6NTuzaIxw=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR10MB1566
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.517,18.0.874
 definitions=2022-06-14_03:2022-06-13,2022-06-14 signatures=0
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 mlxlogscore=904
 bulkscore=0 spamscore=0 phishscore=0 adultscore=0 suspectscore=0
 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1
 engine=8.12.0-2204290000 definitions=main-2206140041
X-Proofpoint-ORIG-GUID: p96gfyBQ_KkGZrBemj5w7wkDwHqNcjiU
X-Proofpoint-GUID: p96gfyBQ_KkGZrBemj5w7wkDwHqNcjiU
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE
        autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 6/12/22 19:23, Gautam Menghani wrote:
> Remove unwanted initialization for the variable 'next'. This fixes the
> clang scan warning: Value stored to 'next' during its initialization is 
> never read [deadcode.DeadStores]
> 
> Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>

Ugh, thanks for catching that:

Reviewed-by: Joao Martins <joao.m.martins@oracle.com>

> ---
>  mm/sparse-vmemmap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
> index f4fa61dbbee3..3008aa7859e0 100644
> --- a/mm/sparse-vmemmap.c
> +++ b/mm/sparse-vmemmap.c
> @@ -737,7 +737,7 @@ static int __meminit vmemmap_populate_compound_pages(unsigned long start_pfn,
>  
>  	size = min(end - start, pgmap_vmemmap_nr(pgmap) * sizeof(struct page));
>  	for (addr = start; addr < end; addr += size) {
> -		unsigned long next = addr, last = addr + size;
> +		unsigned long next, last = addr + size;
>  
>  		/* Populate the head page vmemmap page */
>  		pte = vmemmap_populate_address(addr, node, NULL, NULL);