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=-2.5 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 72AA9ECDFBB for ; Wed, 18 Jul 2018 15:10:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28DB02064D for ; Wed, 18 Jul 2018 15:10:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 28DB02064D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730689AbeGRPsc (ORCPT ); Wed, 18 Jul 2018 11:48:32 -0400 Received: from mx2.suse.de ([195.135.220.15]:56146 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729462AbeGRPsc (ORCPT ); Wed, 18 Jul 2018 11:48:32 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 72FC0AED2; Wed, 18 Jul 2018 15:10:10 +0000 (UTC) Date: Wed, 18 Jul 2018 17:10:09 +0200 From: Michal Hocko To: David Rientjes Cc: Baoquan He , linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, corbet@lwn.net, linux-doc@vger.kernel.org Subject: Re: [PATCH] mm/page_alloc: Deprecate kernelcore=nn and movable_core= Message-ID: <20180718151009.GJ7193@dhcp22.suse.cz> References: <20180717131837.18411-1-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 17-07-18 13:46:43, David Rientjes wrote: > On Tue, 17 Jul 2018, Baoquan He wrote: > > > We can still use 'kernelcore=mirror' or 'movable_node' for the usage > > of hotplug and movable zone. If somebody shows up with a valid usecase > > we can reconsider. > > > > We actively use kernelcore=n%, I had recently added support for the option > in the first place in 4.17. It's certainly not deprecated. > > commit a5c6d6509342785bef53bf9508e1842b303f1878 > Author: David Rientjes > Date: Thu Apr 5 16:23:09 2018 -0700 > > mm, page_alloc: extend kernelcore and movablecore for percent What kind of functionality do you need to not depend on this knob? I mean it is a gross hack and you are basically working around fragmentation issues. ZONE_MOVABLE doesn't seem to be a long term solution here IMHO. -- Michal Hocko SUSE Labs