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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 9FE31C32751 for ; Wed, 31 Jul 2019 13:53:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 73544206A2 for ; Wed, 31 Jul 2019 13:53:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564581235; bh=D9W38JEMvrGlFGnAextQJoYrU/oY9PRlqWlq7dx5HrM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=bf5QD/XRmjI5h1N25asyXTuM+ReT5qLER7FdfrilmQUAA04dkuUzz5d1U2Lv0rOxV l/B6q3bDF+/4xvH9ECPVqZd3LI0JcNcUwr1lNXJEGFNJ2r0oMksW1eFXdrnbAQkWyM OyCwBcyyCdtL/PwFovdFbj+i+M3AVsxYSrpaWe60= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729691AbfGaNxy (ORCPT ); Wed, 31 Jul 2019 09:53:54 -0400 Received: from mx2.suse.de ([195.135.220.15]:42774 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727540AbfGaNxx (ORCPT ); Wed, 31 Jul 2019 09:53:53 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 5EA40AE22; Wed, 31 Jul 2019 13:53:52 +0000 (UTC) Date: Wed, 31 Jul 2019 15:53:51 +0200 From: Michal Hocko To: Qian Cai Cc: akpm@linux-foundation.org, miles.chen@mediatek.com, hannes@cmpxchg.org, vdavydov.dev@gmail.com, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH -next] mm/memcg: fix a -Wparentheses compilation warning Message-ID: <20190731135351.GT9330@dhcp22.suse.cz> References: <1564580753-17531-1-git-send-email-cai@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1564580753-17531-1-git-send-email-cai@lca.pw> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 31-07-19 09:45:53, Qian Cai wrote: > The linux-next commit ("mm/memcontrol.c: fix use after free in > mem_cgroup_iter()") [1] introduced a compilation warning, > > mm/memcontrol.c:1160:17: warning: using the result of an assignment as a > condition without parentheses [-Wparentheses] > } while (memcg = parent_mem_cgroup(memcg)); > ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ > mm/memcontrol.c:1160:17: note: place parentheses around the assignment > to silence this warning > } while (memcg = parent_mem_cgroup(memcg)); > ^ > ( ) > mm/memcontrol.c:1160:17: note: use '==' to turn this assignment into an > equality comparison > } while (memcg = parent_mem_cgroup(memcg)); > ^ > == > > Fix it by adding a pair of parentheses. > > [1] https://lore.kernel.org/linux-mm/20190730015729.4406-1-miles.chen@mediatek.com/ > > Signed-off-by: Qian Cai Thanks for the fix. I assume Andrew is going to squash it into the original patch. Acked-by: Michal Hocko > --- > mm/memcontrol.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 694b6f8776dc..4f66a8305ae0 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1157,7 +1157,7 @@ static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) > do { > __invalidate_reclaim_iterators(memcg, dead_memcg); > last = memcg; > - } while (memcg = parent_mem_cgroup(memcg)); > + } while ((memcg = parent_mem_cgroup(memcg))); > > /* > * When cgruop1 non-hierarchy mode is used, > -- > 1.8.3.1 -- Michal Hocko SUSE Labs