From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by kanga.kvack.org (Postfix) with ESMTP id 941FE6B0003 for ; Wed, 18 Jul 2018 11:10:12 -0400 (EDT) Received: by mail-ed1-f69.google.com with SMTP id r21-v6so1985074edp.23 for ; Wed, 18 Jul 2018 08:10:12 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id p34-v6si1886236edp.402.2018.07.18.08.10.10 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Jul 2018 08:10:11 -0700 (PDT) Date: Wed, 18 Jul 2018 17:10:09 +0200 From: Michal Hocko 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: Sender: owner-linux-mm@kvack.org List-ID: 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 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