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=-10.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 AD25DC433DB for ; Fri, 15 Jan 2021 01:56:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81A6B23A5A for ; Fri, 15 Jan 2021 01:56:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729451AbhAOB4a (ORCPT ); Thu, 14 Jan 2021 20:56:30 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:10723 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726081AbhAOB43 (ORCPT ); Thu, 14 Jan 2021 20:56:29 -0500 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4DH4444R7pzl5Kw; Fri, 15 Jan 2021 09:54:28 +0800 (CST) Received: from [10.174.176.61] (10.174.176.61) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.498.0; Fri, 15 Jan 2021 09:55:44 +0800 Subject: Re: [PATCH v2] cgroup-v1: add disabled controller check in cgroup1_parse_param() To: =?UTF-8?Q?Michal_Koutn=c3=bd?= References: <20201218061755.121205-1-chenzhou10@huawei.com> CC: , , , , From: chenzhou Message-ID: <7804658e-7644-8edb-5ca8-0c97389c8c62@huawei.com> Date: Fri, 15 Jan 2021 09:55:43 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.176.61] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/1/15 0:54, Michal Koutný wrote: > On Thu, Jan 14, 2021 at 10:08:19PM +0800, chenzhou wrote: >> In this case, at the beginning of function check_cgroupfs_options(), the mask >> ctx->subsys_mask will be 0. And if we mount without 'none' and 'name=' options, >> then in check_cgroupfs_options(), the flag ctx->all_ss will be set, that is, select all the subsystems. > But even then, the line > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/kernel/cgroup/cgroup-v1.c?h=v5.11-rc3#n1012 > would select only 'enabled' controllers, wouldn't it? Yeah, this will select all enabled controllers, but which doesn't the behavior we want. I think the case should return error with information "Disabled controller xx" rather than attaching all the other enabled controllers. For example, boot with cgroup_no_v1=cpu, and then mount with "mount -t cgroup -o cpu cpu /sys/fs/cgroup/cpu", then all enabled controllers will be attached expect cpu. > > It's possible I missed something but if this means that cgroup_no_v1= > doesn't hold to its expectations, I'd suggest adding proper Fixes: tag > to the patch. See above. Just the mount behavior isn't what we what. The behavior was changed since commit f5dfb5315d34 ("cgroup: take options parsing into ->parse_monolithic()"), will add this as Fixes. Thanks, Chen Zhou > > Thanks, > Michal