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=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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,USER_AGENT_GIT 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 77477C49EB7 for ; Mon, 14 Jun 2021 11:23:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E718613F0 for ; Mon, 14 Jun 2021 11:23:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235995AbhFNLYH (ORCPT ); Mon, 14 Jun 2021 07:24:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:42830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235629AbhFNLLA (ORCPT ); Mon, 14 Jun 2021 07:11:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5BD7C61944; Mon, 14 Jun 2021 10:47:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623667656; bh=gK/PIRaPplH2AOarruFJFMSYjmI7TyAu/ZGffVNZ/Hg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RiMko76fTkLxADR73QGFuXsqVF7MKuR1TWyVmk/4JAy7HjK/3w0pyQ/mxr570l3xI TrcUS9TCLwmPUv5zmQoYHd4tQ8D6mrTgzXfwLXs7eZoMEOXhmj8RjeyC3+i8DNhcaB BLoXinWS0UjaqTRTk3G5wTRNluHb7DkCBpDdtpOs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shakeel Butt , =?UTF-8?q?NOMURA=20JUNICHI ?= , Tejun Heo , Sasha Levin Subject: [PATCH 5.12 023/173] cgroup: disable controllers at parse time Date: Mon, 14 Jun 2021 12:25:55 +0200 Message-Id: <20210614102658.915601054@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210614102658.137943264@linuxfoundation.org> References: <20210614102658.137943264@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shakeel Butt [ Upstream commit 45e1ba40837ac2f6f4d4716bddb8d44bd7e4a251 ] This patch effectively reverts the commit a3e72739b7a7 ("cgroup: fix too early usage of static_branch_disable()"). The commit 6041186a3258 ("init: initialize jump labels before command line option parsing") has moved the jump_label_init() before parse_args() which has made the commit a3e72739b7a7 unnecessary. On the other hand there are consequences of disabling the controllers later as there are subsystems doing the controller checks for different decisions. One such incident is reported [1] regarding the memory controller and its impact on memory reclaim code. [1] https://lore.kernel.org/linux-mm/921e53f3-4b13-aab8-4a9e-e83ff15371e4@nec.com Signed-off-by: Shakeel Butt Reported-by: NOMURA JUNICHI(野村　淳一) Signed-off-by: Tejun Heo Tested-by: Jun'ichi Nomura Signed-off-by: Sasha Levin --- kernel/cgroup/cgroup.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 9153b20e5cc6..2529d1f88330 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5626,8 +5626,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5686,12 +5684,8 @@ int __init cgroup_init(void) * disabled flag and cftype registration needs kmalloc, * both of which aren't available during early_init. */ - if (cgroup_disable_mask & (1 << ssid)) { - static_branch_disable(cgroup_subsys_enabled_key[ssid]); - printk(KERN_INFO "Disabling %s control group subsystem\n", - ss->name); + if (!cgroup_ssid_enabled(ssid)) continue; - } if (cgroup1_ssid_disabled(ssid)) printk(KERN_INFO "Disabling %s control group subsystem in v1 mounts\n", @@ -6206,7 +6200,10 @@ static int __init cgroup_disable(char *str) if (strcmp(token, ss->name) && strcmp(token, ss->legacy_name)) continue; - cgroup_disable_mask |= 1 << i; + + static_branch_disable(cgroup_subsys_enabled_key[i]); + pr_info("Disabling %s control group subsystem\n", + ss->name); } } return 1; -- 2.30.2