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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 1DC6EC43381 for ; Mon, 1 Apr 2019 11:53:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E008E20883 for ; Mon, 1 Apr 2019 11:53:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554119591; bh=zEhd33Z6TChszaPgs9iRyc9N/w9fyUst27mWujReceE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=1ExTRAGAYotXApHr7sJASLMcLRnZeojXuaJwq2PvMvGq+nFFM7sJOAXsJNFW7HTVW PxzVetchpRHf3RacTNxFAtSwUk+8YeZEATWsePFz2sNKTpnKlfi9zsoqcfK22QXx2T wzE6AU6pqk3x/BqEIGFrpRqubzssSfRsU/IWk/rA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726887AbfDALxJ (ORCPT ); Mon, 1 Apr 2019 07:53:09 -0400 Received: from mx2.suse.de ([195.135.220.15]:40008 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726473AbfDALxJ (ORCPT ); Mon, 1 Apr 2019 07:53:09 -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 D24CDAEC8; Mon, 1 Apr 2019 11:53:07 +0000 (UTC) Date: Mon, 1 Apr 2019 13:53:06 +0200 From: Michal Hocko To: Oscar Salvador Cc: David Hildenbrand , akpm@linux-foundation.org, dan.j.williams@intel.com, Jonathan.Cameron@huawei.com, anshuman.khandual@arm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 0/4] mm,memory_hotplug: allocate memmap from hotadded memory Message-ID: <20190401115306.GF28293@dhcp22.suse.cz> References: <20190328134320.13232-1-osalvador@suse.de> <20190329084547.5k37xjwvkgffwajo@d104.suse.de> <20190329134243.GA30026@dhcp22.suse.cz> <20190401075936.bjt2qsrhw77rib77@d104.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190401075936.bjt2qsrhw77rib77@d104.suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 01-04-19 09:59:36, Oscar Salvador wrote: > On Fri, Mar 29, 2019 at 02:42:43PM +0100, Michal Hocko wrote: > > Having a larger contiguous area is definitely nice to have but you also > > have to consider the other side of the thing. If we have a movable > > memblock with unmovable memory then we are breaking the movable > > property. So there should be some flexibility for caller to tell whether > > to allocate on per device or per memblock. Or we need something to move > > memmaps during the hotremove. > > By movable memblock you mean a memblock whose pages can be migrated over when > this memblock is offlined, right? I am mostly thinking about movable_node kernel parameter which makes newly hotpluged memory go into ZONE_MOVABLE and people do use that to make sure such a memory can be later hotremoved. -- Michal Hocko SUSE Labs