From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751486AbXBNBYO (ORCPT ); Tue, 13 Feb 2007 20:24:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751491AbXBNBYO (ORCPT ); Tue, 13 Feb 2007 20:24:14 -0500 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:43056 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751486AbXBNBYN (ORCPT ); Tue, 13 Feb 2007 20:24:13 -0500 Message-ID: <45D2649D.4080508@vmware.com> Date: Tue, 13 Feb 2007 17:23:41 -0800 From: Dan Hecht User-Agent: Thunderbird 1.5.0.2 (X11/20060420) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Andi Kleen , Andrew Morton , virtualization@lists.osdl.org, xen-devel@lists.xensource.com, Chris Wright , linux-kernel@vger.kernel.org Subject: Re: [patch 05/21] Xen-paravirt: paravirt_ops: allocate a fixmap slot References: <20070213221729.772002682@goop.org> <20070213221829.845132535@goop.org> In-Reply-To: <20070213221829.845132535@goop.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 14 Feb 2007 01:24:12.0785 (UTC) FILETIME=[D58ECE10:01C74FD6] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 02/13/2007 02:17 PM, Jeremy Fitzhardinge wrote: > Allocate a fixmap slot for use by a paravirt_ops implementation. Xen > uses this to map the hypervisor's shared info page, which doesn't have > a pseudo-physical page number, and therefore can't be mapped > ordinarily. > Why doesn't Xen allocate the shared_info page from the pseudo-physical space? Doesn't it already have to steal pages from the pseudo-physical space for e.g. initial page tables, console, etc? Why not do the same for shared_info, and then you don't need a reserve the fixmap slot. Dan