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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 46489C43331 for ; Wed, 13 Jan 2021 00:56:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 214C923131 for ; Wed, 13 Jan 2021 00:56:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730131AbhAMAms (ORCPT ); Tue, 12 Jan 2021 19:42:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:45964 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391937AbhALXtx (ORCPT ); Tue, 12 Jan 2021 18:49:53 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9FE9423133; Tue, 12 Jan 2021 23:49:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1610495352; bh=8koHiLzr5itWHBQjzON8eFAiTv4vMLkrNnLaFsHT9XY=; h=Date:From:To:Subject:In-Reply-To:From; b=lvXeWdYGaZjPsNQua6b0I/SrPqjOlXOMOSbc4SSJ5y3fgoy912qIodtDGyb0YU1bi zeBUIy/iJxOm0/sQl8fQt/8zI+wXmqrXhZ4k+6awc8FaEm2eT1u0esMXL19rvNxbT6 SQ8iwPzepdSWuLj/FBlwrJbZtdbHsqfTUORb/t4Q= Date: Tue, 12 Jan 2021 15:49:11 -0800 From: Andrew Morton To: akpm@linux-foundation.org, alex.shi@linux.alibaba.com, bhe@redhat.com, chris@chrisdown.name, guro@fb.com, hannes@cmpxchg.org, hughd@google.com, linux-mm@kvack.org, lstoakes@gmail.com, mhocko@suse.com, mm-commits@vger.kernel.org, sh_def@163.com, shakeelb@google.com, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 03/10] mm/memcontrol: fix warning in mem_cgroup_page_lruvec() Message-ID: <20210112234911.PDWRysjU0%akpm@linux-foundation.org> In-Reply-To: <20210112154839.abeb6e57de79480059fd9b0e@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Hugh Dickins Subject: mm/memcontrol: fix warning in mem_cgroup_page_lruvec() Boot a CONFIG_MEMCG=y kernel with "cgroup_disabled=memory" 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(). 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(). 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(). Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2101032056260.1093@eggly.anvils Fixes: 9a1ac2288cf1 ("mm/memcontrol:rewrite mem_cgroup_page_lruvec()") Signed-off-by: Hugh Dickins Reviewed-by: Alex Shi Acked-by: Roman Gushchin Acked-by: Chris Down Reviewed-by: Baoquan He Acked-by: Vlastimil Babka Cc: Hui Su Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Johannes Weiner Cc: Shakeel Butt Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/memcontrol.h~mm-memcontrol-fix-warning-in-mem_cgroup_page_lruvec +++ a/include/linux/memcontrol.h @@ -665,7 +665,7 @@ static inline struct lruvec *mem_cgroup_ { struct mem_cgroup *memcg = page_memcg(page); - VM_WARN_ON_ONCE_PAGE(!memcg, page); + VM_WARN_ON_ONCE_PAGE(!memcg && !mem_cgroup_disabled(), page); return mem_cgroup_lruvec(memcg, pgdat); } _