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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 C8D3AC2D0BF for ; Tue, 17 Dec 2019 15:17:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99DAD21D7D for ; Tue, 17 Dec 2019 15:17:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="d9bCdpSb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728279AbfLQPRP (ORCPT ); Tue, 17 Dec 2019 10:17:15 -0500 Received: from mail-qk1-f194.google.com ([209.85.222.194]:37105 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727756AbfLQPRN (ORCPT ); Tue, 17 Dec 2019 10:17:13 -0500 Received: by mail-qk1-f194.google.com with SMTP id 21so5789175qky.4 for ; Tue, 17 Dec 2019 07:17:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=QBbJhTwA/z9GheRdVz6DmV0ve21qD4tE529ywgzTv4I=; b=d9bCdpSbGIQ2bZQYmFNSt27dYg2M8iWZwhztIVSpbfasIXUPfe9wfODDgBXYwS+JyO Gv3TTGJk82AvVWFURXKuscdcGA0HsfV01pD/QIDsVJmelRXOfAde709zspdbcG8ICcc7 7TNB7KXnhm1FIo4TfOcfXQvk5nlWUU9HlOKjB4BCaP67Vuf1CgtKnicQw9mirkKllLU2 M/a7YslEdG6U+m8J2FZ77M+8bRBnh3JeZWOf4vPXkFIzi7HAeKhBmRNHQe1i7gyA1pzn a8+ey1AIdl0lgF0SWzVjIXgYk2NCOn6AkDxukN3hUDa+fNb/qaSLFPWl6523TIa7FcdY zL8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=QBbJhTwA/z9GheRdVz6DmV0ve21qD4tE529ywgzTv4I=; b=dz+1Ed0pW8gAzENXNgdyD1OUcil2GcJIPEQIA7f1XL37Pe/1Nscce546uNpwPMfKjr I3D2g/vyn4yy4YawH2ofDO08CAT0ZVODDc4EloQQTnoPS4OkD4DBLeB31Q19XArildxn KPR3JcIwu0VGigUvxGHQprqbp0GxtYbAOZaaLmQ3XZ/FVCKPuwm3/t1HlYV3oWaIyXwt tPdatT+BsOVV7F3K8U2qAjgz5SjaK4ZTnBXy9LEor/xmXmK1HULiZyEjCtbTkZ/+Nz67 Xi6B7gGj3GIsaURcvaWqqalocDsQKtPNTqxY2tyPbVQjG2SHb5o9n4jrk09LoGo8Myk5 JQpw== X-Gm-Message-State: APjAAAW2ScZjO5+GZGCWByDn/3O0j6NHJjZyv9KP/6gxdlX83in0l4pW fUWWV5/dXId/xPmJDnLVI5Fs+Q== X-Google-Smtp-Source: APXvYqxc4OvUcMuruBVNLedZUEl90a9Pdz8xXR4S1pf38oV2+oQQJTx99hLJYlWM6tZGPH1Gp7jarA== X-Received: by 2002:a37:6294:: with SMTP id w142mr5114586qkb.284.1576595832242; Tue, 17 Dec 2019 07:17:12 -0800 (PST) Received: from [192.168.1.183] (pool-71-184-117-43.bstnma.fios.verizon.net. [71.184.117.43]) by smtp.gmail.com with ESMTPSA id t7sm7120087qkm.136.2019.12.17.07.17.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Dec 2019 07:17:11 -0800 (PST) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH] mm: memcontrol.c: move mem_cgroup_id_get_many under CONFIG_MMU Date: Tue, 17 Dec 2019 10:17:10 -0500 Message-Id: References: <20191217151343.GC7272@dhcp22.suse.cz> Cc: Chris Down , Kuninori Morimoto , Johannes Weiner , Vladimir Davydov , Andrew Morton , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <20191217151343.GC7272@dhcp22.suse.cz> To: Michal Hocko X-Mailer: iPhone Mail (17C54) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Dec 17, 2019, at 10:13 AM, Michal Hocko wrote: >=20 > I do understand the general purpose of the warning. I am simply not sure > the kernel tree is a good candidate with a huge number of different > config combinations that might easily result in warnings which would > tend to result in even more ifdeferry than we have. Yes, compiling test without real-world use case is evil. Once we ignore the e= vil, it becomes much more manageable.=