Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932426AbXBPVuf (ORCPT ); Fri, 16 Feb 2007 16:50:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932599AbXBPVuf (ORCPT ); Fri, 16 Feb 2007 16:50:35 -0500 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:40738 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932426AbXBPVue (ORCPT ); Fri, 16 Feb 2007 16:50:34 -0500 Message-ID: <45D626BB.20007@vmware.com> Date: Fri, 16 Feb 2007 13:48:43 -0800 From: Zachary Amsden User-Agent: Thunderbird 1.5.0.9 (X11/20061206) MIME-Version: 1.0 To: Christoph Lameter CC: Jeremy Fitzhardinge , Andi Kleen , Andrew Morton , linux-kernel@vger.kernel.org, virtualization@lists.osdl.org, xen-devel@lists.xensource.com, Chris Wright , Rusty Russell Subject: Re: [patch 00/21] Xen-paravirt: Xen guest implementation for paravirt_ops interface References: <20070216022449.739760547@goop.org> <45D61C74.2000601@vmware.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1336 Lines: 30 Christoph Lameter wrote: > On Fri, 16 Feb 2007, Zachary Amsden wrote: > > >> For the most part, it doesn't disturb VMware or KVM. Xen does need some >> additional functionality in paravirt-ops because they took a different design >> choice - direct page tables instead of shadow page tables. This is where all >> the requirements for the new Xen paravirt-ops hooks come from. >> > > It still seems to be implemented for Xen and not to support a variety of > page table methods in paravirt ops. > Yes, but that is just because the Xen hooks happens to be near the last part of the merge. VMI required some special hooks, as do both Xen and lhype (I think ... Rusty can correct me if lhype's puppy's have precluded the addition of new hooks). Xen page table handling is very different, mostly it is trap and emulate so writable page tables can work, which means they don't always issue hypercalls for PTE updates, although they do have that option, should the hypervisor MMU model change, or performance concerns prompt a different model (or perhaps, migration?) Zach - 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/