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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,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 0A0A2C43215 for ; Wed, 20 Nov 2019 11:42:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6C3021906 for ; Wed, 20 Nov 2019 11:42:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729353AbfKTLmv (ORCPT ); Wed, 20 Nov 2019 06:42:51 -0500 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:56241 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728343AbfKTLmu (ORCPT ); Wed, 20 Nov 2019 06:42:50 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R811e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04395;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0Tie.HNt_1574250166; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0Tie.HNt_1574250166) by smtp.aliyun-inc.com(127.0.0.1); Wed, 20 Nov 2019 19:42:47 +0800 Subject: Re: [PATCH v4 1/9] mm/swap: fix uninitialized compiler warning To: Johannes Weiner Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, willy@infradead.org, shakeelb@google.com References: <1574166203-151975-1-git-send-email-alex.shi@linux.alibaba.com> <1574166203-151975-2-git-send-email-alex.shi@linux.alibaba.com> <20191119154138.GB382712@cmpxchg.org> From: Alex Shi Message-ID: <919a5a57-1b7a-b109-491f-2b8b099390fe@linux.alibaba.com> Date: Wed, 20 Nov 2019 19:42:46 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <20191119154138.GB382712@cmpxchg.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2019/11/19 下午11:41, Johannes Weiner 写道: > On Tue, Nov 19, 2019 at 08:23:15PM +0800, Alex Shi wrote: >> ../mm/swap.c: In function ‘__page_cache_release’: >> ../mm/swap.c:67:10: warning: ‘flags’ may be used uninitialized in this >> function [-Wmaybe-uninitialized] >> lruvec = lock_page_lruvec_irqsave(page, pgdat, flags); >> ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > At this point in the series, there is no lock_page_lruvec_irqsave() > yet, so this patch is out of order. Please don't do that. It's very > hard to review patches that depend on later changes to make sense. > Sorry, I will be more careful on this. >> Signed-off-by: Alex Shi >> Cc: Andrew Morton >> Cc: linux-mm@kvack.org >> Cc: linux-kernel@vger.kernel.org >> --- >> mm/swap.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/swap.c b/mm/swap.c >> index 5341ae93861f..c36a10244d07 100644 >> --- a/mm/swap.c >> +++ b/mm/swap.c >> @@ -62,7 +62,7 @@ static void __page_cache_release(struct page *page) >> if (PageLRU(page)) { >> pg_data_t *pgdat = page_pgdat(page); >> struct lruvec *lruvec; >> - unsigned long flags; >> + unsigned long flags = 0; > Use unintialized_var() for these cases to make the intent clear. Thanks for suggestion!