Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758361AbYHGWRt (ORCPT ); Thu, 7 Aug 2008 18:17:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753838AbYHGWRj (ORCPT ); Thu, 7 Aug 2008 18:17:39 -0400 Received: from terminus.zytor.com ([198.137.202.10]:58142 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753125AbYHGWRi (ORCPT ); Thu, 7 Aug 2008 18:17:38 -0400 Message-ID: <489B7470.5030408@kernel.org> Date: Thu, 07 Aug 2008 15:17:20 -0700 From: "H. Peter Anvin" Organization: Linux Kernel Organization, Inc. User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Zachary Amsden CC: Alok Kataria , "torvalds@linux-foundation.org" , Ingo Molnar , the arch/x86 maintainers , LKML Subject: Re: [PATCH]Fix broken VMI in 2.6.27-rc.. References: <1218136365.23770.52.camel@alok-dev1> <489B6710.9000604@kernel.org> <1218144438.20178.336.camel@bodhitayantram.eng.vmware.com> <489B6A5C.8030400@kernel.org> <1218145344.20178.347.camel@bodhitayantram.eng.vmware.com> <489B6E83.7000202@kernel.org> <1218146154.20178.352.camel@bodhitayantram.eng.vmware.com> In-Reply-To: <1218146154.20178.352.camel@bodhitayantram.eng.vmware.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 977 Lines: 23 Zachary Amsden wrote: > >> Realistically speaking, any (virtual) machine which does *not* have a >> full complement of lowmem (i.e. less than 896 MB in the common case) >> will not suffer significatly from losing a few megabytes of address space. > > Yes, the reason to make the fixmap moveable is to allow as much address > space as possible for big memory (physical) machines. > That being said, the fixmap area being movable more than kind of defeats a major point of the fixmap area; the addresses in it are no longer fixed. The only way I can see around that, though, is to move the 1:1 mapping base up by 2/4 MB (for PAE/no PAE, respectively) and put the fixmap area there. Kind of sucks, but would be doable. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/