From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753157AbbJSCkK (ORCPT ); Sun, 18 Oct 2015 22:40:10 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:57082 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752672AbbJSCkI (ORCPT ); Sun, 18 Oct 2015 22:40:08 -0400 Message-ID: <5624548F.30500@huawei.com> Date: Mon, 19 Oct 2015 10:25:19 +0800 From: Xishi Qiu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Taku Izumi CC: , , , , , , , Subject: Re: [PATCH] mm: Introduce kernelcore=reliable option References: <1444915942-15281-1-git-send-email-izumi.taku@jp.fujitsu.com> In-Reply-To: <1444915942-15281-1-git-send-email-izumi.taku@jp.fujitsu.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.25.179] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/10/15 21:32, Taku Izumi wrote: > Xeon E7 v3 based systems supports Address Range Mirroring > and UEFI BIOS complied with UEFI spec 2.5 can notify which > ranges are reliable (mirrored) via EFI memory map. > Now Linux kernel utilize its information and allocates > boot time memory from reliable region. > > My requirement is: > - allocate kernel memory from reliable region > - allocate user memory from non-reliable region > > In order to meet my requirement, ZONE_MOVABLE is useful. > By arranging non-reliable range into ZONE_MOVABLE, > reliable memory is only used for kernel allocations. > > This patch extends existing "kernelcore" option and > introduces kernelcore=reliable option. By specifying > "reliable" instead of specifying the amount of memory, > non-reliable region will be arranged into ZONE_MOVABLE. > > Earlier discussion is at: > https://lkml.org/lkml/2015/10/9/24 > Hi Taku, If user don't want to waste a lot of memory, and he only set a few memory to mirrored memory, then the kernelcore is very small, right? That means OS will have a very small normal zone and a very large movable zone. Kernel allocation could only use the unmovable zone. As the normal zone is very small, the kernel allocation maybe OOM, right? Do you mean that we will reuse the movable zone in short-term solution and create a new zone(mirrored zone) in future? Thanks, Xishi Qiu