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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 8414DC47082 for ; Thu, 3 Jun 2021 17:16:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F369613F8 for ; Thu, 3 Jun 2021 17:16:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233912AbhFCRSd (ORCPT ); Thu, 3 Jun 2021 13:18:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:43672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232238AbhFCROS (ORCPT ); Thu, 3 Jun 2021 13:14:18 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7B48C6140B; Thu, 3 Jun 2021 17:11:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622740262; bh=QoxxFQ0dAv0B4Il9IHIAqp5Qvs1fImb2V7//DS7Y33k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q7NCV4qI2vG+3GQ2pZY9Lex1ZHRJPF72G7Uh1gxESsLMvMlSRoxIWxcOz6PANQKAh 2yB/RzI0gRgekFYI6Zxj8G2rq6lNKWzcWCPFpQH8lZPBja+mmAjHJDWPG0Dr8HxMTc gga08wvWbLzSqqVsNKnsX+TU+fiiBXmxyHWQ/Sixf+TSSpE+ONTpp4uUaK61ydd8uT I9UY7jsUnhWCdYINc6bnNwhByCrjuBJkFsJH96uQuk3nzwT0H2zl4gw94yoo6tHTLq rtXLPNPQvcvusbQdI5cYhZT6t4Dju4kdpcNAcK6fmUMCbFNwp89qF85mqQ2Cb7S4ND U/AKStlRUZM+g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Shakeel Butt , NOMURA JUNICHI , Tejun Heo , Sasha Levin Subject: [PATCH AUTOSEL 4.9 07/17] cgroup: disable controllers at parse time Date: Thu, 3 Jun 2021 13:10:42 -0400 Message-Id: <20210603171052.3169893-7-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210603171052.3169893-1-sashal@kernel.org> References: <20210603171052.3169893-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore 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.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 684d02f343b4..3e0fca894a8b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5636,8 +5636,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5695,12 +5693,8 @@ 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 (cgroup_ssid_no_v1(ssid)) printk(KERN_INFO "Disabling %s control group subsystem in v1 mounts\n", @@ -6143,7 +6137,10 @@ 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