From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753348AbeBLRZD (ORCPT ); Mon, 12 Feb 2018 12:25:03 -0500 Received: from mail-qk0-f194.google.com ([209.85.220.194]:36399 "EHLO mail-qk0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752822AbeBLRZC (ORCPT ); Mon, 12 Feb 2018 12:25:02 -0500 X-Google-Smtp-Source: AH8x2245O8WHPvJ5XYkVi6rDQlmc+0pRKKjkvxXSIcbPM4aIOHMhaCED4maVqVBzsPIE/i5jw4AMAQ== Date: Mon, 12 Feb 2018 09:24:58 -0800 From: Tejun Heo To: Ingo Molnar , Peter Zijlstra Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Li Zefan , Johannes Weiner Subject: Re: [PATCH v4.15-rc9] sched, cgroup: Don't reject lower cpu.max on ancestors Message-ID: <20180212172458.GF695913@devbig577.frc2.facebook.com> References: <20180122192618.GA1771050@devbig577.frc2.facebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180122192618.GA1771050@devbig577.frc2.facebook.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 22, 2018 at 11:26:18AM -0800, Tejun Heo wrote: > While adding cgroup2 interface for the cpu controller, 0d5936344f30 > ("sched: Implement interface for cgroup unified hierarchy") forgot to > update input validation and left it to reject cpu.max config if any > descendant has set a higher value. > > cgroup2 officially supports delegation and a descendant must not be > able to restrict what its ancestors can configure. For absolute > limits such as cpu.max and memory.max, this means that the config at > each level should only act as the upper limit at that level and > shouldn't interfere with what other cgroups can configure. > > This patch updates config validation on cgroup2 so that the cpu > controller follows the same convention. > > Signed-off-by: Tejun Heo > Fixes: 0d5936344f30 ("sched: Implement interface for cgroup unified hierarchy") Applied to cgroup/for-4.16-fixes. Thanks. -- tejun