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=-25.1 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL 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 93870C433E6 for ; Mon, 4 Jan 2021 05:05:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51D7F2151B for ; Mon, 4 Jan 2021 05:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727288AbhADFEz (ORCPT ); Mon, 4 Jan 2021 00:04:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725889AbhADFEy (ORCPT ); Mon, 4 Jan 2021 00:04:54 -0500 Received: from mail-oi1-x22c.google.com (mail-oi1-x22c.google.com [IPv6:2607:f8b0:4864:20::22c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE1A9C061574 for ; Sun, 3 Jan 2021 21:04:13 -0800 (PST) Received: by mail-oi1-x22c.google.com with SMTP id 15so30946365oix.8 for ; Sun, 03 Jan 2021 21:04:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:user-agent:mime-version; bh=dEV0wZXe8t4cW6sTq8NdrlzUWo8syyjgpiwm3vuG8Cw=; b=c/F6Ym9/e/H4Pj5c5Ix6yhLWlC914Jqt6+hjcjTM1vJaXcGUv5/Ls4WJeLTuCK6l4F maEkoE8SKMoS4aL7RCMV/SBT6NDGhJbLcy0p6mDfLaWfAeifE2wXZfxf4tdK5eQxJQDv hmvsuj5JCL5Eqr0z4kCNuPl48/+AyRsmSWBGrjYcAv9NjCZBKNjXOW6NLPMPpH8hX+8R CF+EPz1pOg0gyzFulPim0pcLdBQeddBlKnn8yX4NjnsrRwhkz0a/Y2/mfT+yOf2ozKzd Cy2VqbooOgyJMGB78lEYWrf4b/jzk8M6wtLAOrxa28zHs3HDinRnFjVIVJS2CmMMQ13G I9gg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:user-agent :mime-version; bh=dEV0wZXe8t4cW6sTq8NdrlzUWo8syyjgpiwm3vuG8Cw=; b=ShLEhOeAGCkSgpcdoKCfII5omSt5/3ZYqjK+ji0yLswceXMspCkQAW65ZUJEJlXH0m 8tzJFU2X5SLLLm8gpZKkehYDN6jAor3I4j9s5CumB/xKyUdTLuKXr+lExq4O4tX3MV10 pYw5Yh+HHn8CxwCzYD2sY9Ua1lQOwDD9vFPVlAMjoXOB2fv+nJQ/Zxrzo6UEKiguw2/b yWnDGFVQCjhhgz00ZiXPmGWz3UnG9RO+0+9CTmh/v3Sm7cCRyjEOZaGUQ49v4En9hGoo Lzz54nb6gI3OyF1hG8owJ+M6lWBTjpJ0RYW47Gy7n1SUhmATtT65AAFC/84AUqLZUUuZ DREg== X-Gm-Message-State: AOAM530P1ZFmcLQme8EusP0PCTxdyt82N4TWit1GCA05kBOwwwJZQSof BN5sASIVSMDZiKELaRnznGAqaQ== X-Google-Smtp-Source: ABdhPJwUENfJggxNQsrF/y2HWOhsCRk/hrxcIqAn6mtWboxwkSJ3JlsSCEWuqbwbiVjOjvU5W1W4hA== X-Received: by 2002:aca:5786:: with SMTP id l128mr16891541oib.145.1609736652718; Sun, 03 Jan 2021 21:04:12 -0800 (PST) Received: from eggly.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id d10sm9326911ooh.32.2021.01.03.21.04.11 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Sun, 03 Jan 2021 21:04:12 -0800 (PST) Date: Sun, 3 Jan 2021 21:03:58 -0800 (PST) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Andrew Morton cc: Hui Su , Alex Shi , Lorenzo Stoakes , Michal Hocko , Johannes Weiner , Shakeel Butt , Roman Gushchin , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH] mm/memcontrol: fix warning in mem_cgroup_page_lruvec() Message-ID: User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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(). Fixes: 9a1ac2288cf1 ("mm/memcontrol:rewrite mem_cgroup_page_lruvec()") Signed-off-by: Hugh Dickins --- include/linux/memcontrol.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 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 -0800 @@ -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); }