Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752173AbdC1Ptb (ORCPT ); Tue, 28 Mar 2017 11:49:31 -0400 Received: from mail.kernel.org ([198.145.29.136]:34600 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751386AbdC1Pt3 (ORCPT ); Tue, 28 Mar 2017 11:49:29 -0400 Date: Tue, 28 Mar 2017 08:49:14 -0700 From: Shaohua Li To: Ming Lei Cc: Stephen Rothwell , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: linux-next: build warning after merge of the md tree Message-ID: <20170328154914.tkowin5hm5biybd6@kernel.org> References: <20170328154022.4aad73b6@canb.auug.org.au> <20170328081753.GA6743@ming.t460p> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170328081753.GA6743@ming.t460p> User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2387 Lines: 72 On Tue, Mar 28, 2017 at 04:17:55PM +0800, Ming Lei wrote: > Hi, > > On Tue, Mar 28, 2017 at 03:40:22PM +1100, Stephen Rothwell wrote: > > Hi Shaohua, > > > > After merging the md tree, today's linux-next build (powerpc > > pseries_le_defconfig) produced this warning: > > > > drivers/md/raid1.c: In function 'raid1d': > > drivers/md/raid1.c:2172:9: warning: 'page_len$' may be used uninitialized in this function [-Wmaybe-uninitialized] > > if (memcmp(page_address(ppages[j]), > > ^ > > drivers/md/raid1.c:2160:7: note: 'page_len$' was declared here > > int page_len[RESYNC_PAGES]; > > ^ > > > > Introduced by commit > > > > 60928a91b0b3 ("md: raid1: use bio helper in process_checks()") > > It is a false positive, and looks we have to initialize it for killing > the warning since I don't find a annotation for addressing uninitialized > array. > > So how about the following patch? thanks, added. > --- > > From 73fd5ba571465d764fc0cf73fc4169d222dd676a Mon Sep 17 00:00:00 2001 > From: Ming Lei > Date: Tue, 28 Mar 2017 16:09:13 +0800 > Subject: [PATCH] md: raid1: kill warning on powerpc_pseries > > This patch kills the warning reported on powerpc_pseries, > and actually we don't need the initialization. > > After merging the md tree, today's linux-next build (powerpc > pseries_le_defconfig) produced this warning: > > drivers/md/raid1.c: In function 'raid1d': > drivers/md/raid1.c:2172:9: warning: 'page_len$' may be used uninitialized in this function [-Wmaybe-uninitialized] > if (memcmp(page_address(ppages[j]), > ^ > drivers/md/raid1.c:2160:7: note: 'page_len$' was declared here > int page_len[RESYNC_PAGES]; > ^ > > Signed-off-by: Ming Lei > --- > drivers/md/raid1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c > index 3c13286190c1..7e6350334d8e 100644 > --- a/drivers/md/raid1.c > +++ b/drivers/md/raid1.c > @@ -2172,7 +2172,7 @@ static void process_checks(struct r1bio *r1_bio) > struct page **ppages = get_resync_pages(pbio)->pages; > struct page **spages = get_resync_pages(sbio)->pages; > struct bio_vec *bi; > - int page_len[RESYNC_PAGES]; > + int page_len[RESYNC_PAGES] = { 0 }; > > if (sbio->bi_end_io != end_sync_read) > continue; > -- > 2.9.3 > >