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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 80D94C433E0 for ; Mon, 4 Jan 2021 08:11:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0761C20702 for ; Mon, 4 Jan 2021 08:11:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0761C20702 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 001828D0008; Mon, 4 Jan 2021 03:11:26 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EF4CB8D0002; Mon, 4 Jan 2021 03:11:25 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DE2048D0008; Mon, 4 Jan 2021 03:11:25 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0242.hostedemail.com [216.40.44.242]) by kanga.kvack.org (Postfix) with ESMTP id C5FE68D0002 for ; Mon, 4 Jan 2021 03:11:25 -0500 (EST) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 81EAB3629 for ; Mon, 4 Jan 2021 08:11:25 +0000 (UTC) X-FDA: 77667372930.16.step76_1e0cd87274ce Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin16.hostedemail.com (Postfix) with ESMTP id 646FD100E6903 for ; Mon, 4 Jan 2021 08:11:25 +0000 (UTC) X-HE-Tag: step76_1e0cd87274ce X-Filterd-Recvd-Size: 2928 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Mon, 4 Jan 2021 08:11:24 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R211e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0UKeYYmw_1609747872; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0UKeYYmw_1609747872) by smtp.aliyun-inc.com(127.0.0.1); Mon, 04 Jan 2021 16:11:13 +0800 Subject: Re: [PATCH] mm/memcontrol: fix warning in mem_cgroup_page_lruvec() To: Hugh Dickins , Andrew Morton Cc: Hui Su , Lorenzo Stoakes , Michal Hocko , Johannes Weiner , Shakeel Butt , Roman Gushchin , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: From: Alex Shi Message-ID: <2c1083cb-53d6-1cd6-9e1b-14a501db6f9a@linux.alibaba.com> Date: Mon, 4 Jan 2021 16:11:12 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.0; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: quoted-printable 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: Reviewed-by: Alex Shi =D4=DA 2021/1/4 =CF=C2=CE=E71:03, Hugh Dickins =D0=B4=B5=C0: > Boot a CONFIG_MEMCG=3Dy kernel with "cgroup_disabled=3Dmemory" and you = are > met by a series of warnings from the VM_WARN_ON_ONCE_PAGE(!memcg, page) > recently added to the inline mem_cgroup_page_lruvec(). >=20 > An earlier attempt to place that warning, in mem_cgroup_lruvec(), had > been careful to do so after weeding out the mem_cgroup_disabled() case; > but was itself invalid because of the mem_cgroup_lruvec(NULL, pgdat) in > clear_pgdat_congested() and age_active_anon(). >=20 > Warning in mem_cgroup_page_lruvec() was once useful in detecting a KSM > charge bug, so may be worth keeping: but skip if mem_cgroup_disabled(). >=20 > Fixes: 9a1ac2288cf1 ("mm/memcontrol:rewrite mem_cgroup_page_lruvec()") > Signed-off-by: Hugh Dickins > --- >=20 > include/linux/memcontrol.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > --- 5.11-rc2/include/linux/memcontrol.h 2020-12-27 20:39:36.751923135 -= 0800 > +++ linux/include/linux/memcontrol.h 2021-01-03 19:38:24.822978559 -080= 0 > @@ -665,7 +665,7 @@ static inline struct lruvec *mem_cgroup_ > { > struct mem_cgroup *memcg =3D page_memcg(page); > =20 > - VM_WARN_ON_ONCE_PAGE(!memcg, page); > + VM_WARN_ON_ONCE_PAGE(!memcg && !mem_cgroup_disabled(), page); > return mem_cgroup_lruvec(memcg, pgdat); > } > =20 >=20