From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756180AbZCBVjo (ORCPT ); Mon, 2 Mar 2009 16:39:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750772AbZCBVjf (ORCPT ); Mon, 2 Mar 2009 16:39:35 -0500 Received: from hera.kernel.org ([140.211.167.34]:36955 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753330AbZCBVjf (ORCPT ); Mon, 2 Mar 2009 16:39:35 -0500 Message-ID: <49AC51D7.1080203@kernel.org> Date: Mon, 02 Mar 2009 13:38:31 -0800 From: Yinghai Lu User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Huang Ying CC: Brian Maly , Ingo Molnar , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] Fix e820 end address with EFI References: <49A965AD.10701@redhat.com> <86802c440902282142p14f623b8td8a88600ff2a6bbe@mail.gmail.com> <49AAEC79.3000808@redhat.com> <1235956068.6204.143.camel@yhuang-dev.sh.intel.com> <49AB38E7.60305@redhat.com> <1235960016.6204.170.camel@yhuang-dev.sh.intel.com> <49AB4171.7000508@kernel.org> <1235960708.6204.176.camel@yhuang-dev.sh.intel.com> <49AB4521.8010909@kernel.org> <1235961428.6204.190.camel@yhuang-dev.sh.intel.com> <86802c440903011851t17e240eu9dc25116a40ca85e@mail.gmail.com> <1235979959.6204.212.camel@yhuang-dev.sh.intel.com> In-Reply-To: <1235979959.6204.212.camel@yhuang-dev.sh.intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Huang Ying wrote: > On Mon, 2009-03-02 at 10:51 +0800, Yinghai Lu wrote: >> On Sun, Mar 1, 2009 at 6:37 PM, Huang Ying wrote: >>>> so 64bit could use ioremap_cache() too? >>>> we may keep 32bit and 64bit a bit consistent. >>> If we use ioremap_cache(), kexec runtime service will not work in kexec >>> situation, which needs EFI runtime memory area to be mapped at exact >>> same location across kexec. I think we should support kexec if possible. >> >> sure. >> >> please don't touch max_low_pfn_mapped, because some range may not >> directly mapped under those efi run-time code > > Find an issue to use init_memory_mapping() here. > > If the memory range to be mapped is less than 2M, the last mapped > address may be next 2M aligned position, this may lead mapping > overlapping between memory range. Such as: > > 0x3f388000 - 0x3f488000: real mapped 0x3f388000 - 0x3f600000 > 0x3f590000 - 0x3f5bb000: real mapped 0x3f590000 - 0x3f600000 > > The problem is that the memory range 0x3f400000 - 0x3f590000 is left not > mapped! what is max_low_pfn_mapped before that? YH