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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 455EFC4320A for ; Wed, 11 Aug 2021 01:21:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C522560EE9 for ; Wed, 11 Aug 2021 01:21:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C522560EE9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 178CD6B0073; Tue, 10 Aug 2021 21:21:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 12A7D6B0074; Tue, 10 Aug 2021 21:21:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 066396B0075; Tue, 10 Aug 2021 21:21:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0227.hostedemail.com [216.40.44.227]) by kanga.kvack.org (Postfix) with ESMTP id E4E646B0073 for ; Tue, 10 Aug 2021 21:21:57 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 94A59181C65E9 for ; Wed, 11 Aug 2021 01:21:57 +0000 (UTC) X-FDA: 78461048274.03.F2CA627 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf25.hostedemail.com (Postfix) with ESMTP id 015F1B003B5B for ; Wed, 11 Aug 2021 01:21:56 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10072"; a="213175783" X-IronPort-AV: E=Sophos;i="5.84,311,1620716400"; d="scan'208";a="213175783" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Aug 2021 18:21:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,311,1620716400"; d="scan'208";a="516260061" Received: from shbuild999.sh.intel.com (HELO localhost) ([10.239.146.151]) by FMSMGA003.fm.intel.com with ESMTP; 10 Aug 2021 18:21:50 -0700 Date: Wed, 11 Aug 2021 09:21:49 +0800 From: Feng Tang To: Nathan Chancellor Cc: aarcange@redhat.com, ak@linux.intel.com, akpm@linux-foundation.org, ben.widawsky@intel.com, dan.j.williams@intel.com, dave.hansen@intel.com, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mgorman@techsingularity.net, mhocko@suse.com, mike.kravetz@oracle.com, rdunlap@infradead.org, rientjes@google.com, vbabka@suse.cz, ying.huang@intel.com Subject: Re: [PATCH] mm/hugetlb: Initialize page to NULL in alloc_buddy_huge_page_with_mpol() Message-ID: <20210811012149.GA2474@shbuild999.sh.intel.com> References: <20210809024430.GA46432@shbuild999.sh.intel.com> <20210810200632.3812797-1-nathan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210810200632.3812797-1-nathan@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 015F1B003B5B Authentication-Results: imf25.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf25.hostedemail.com: domain of feng.tang@intel.com has no SPF policy when checking 192.55.52.120) smtp.mailfrom=feng.tang@intel.com X-Stat-Signature: ap9seob9y7q6g9uwz7zujttj8gxwpdwt X-HE-Tag: 1628644916-540063 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 Tue, Aug 10, 2021 at 01:06:32PM -0700, Nathan Chancellor wrote: > Clang warns: > > mm/hugetlb.c:2162:6: warning: variable 'page' is used uninitialized > whenever 'if' condition is false [-Wsometimes-uninitialized] > if (mpol_is_preferred_many(mpol)) { > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ > mm/hugetlb.c:2172:7: note: uninitialized use occurs here > if (!page) > ^~~~ > mm/hugetlb.c:2162:2: note: remove the 'if' if its condition is always > true > if (mpol_is_preferred_many(mpol)) { > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > mm/hugetlb.c:2155:19: note: initialize the variable 'page' to silence > this warning > struct page *page; > ^ > = NULL > 1 warning generated. > > Initialize page to NULL like in dequeue_huge_page_vma() so that page is > not used uninitialized. > > Signed-off-by: Nathan Chancellor Thanks for the catch! In my original patch, I initialized it in one function, but overlooked this one. Thanks, Feng