Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759540AbXINUxh (ORCPT ); Fri, 14 Sep 2007 16:53:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756231AbXINUxa (ORCPT ); Fri, 14 Sep 2007 16:53:30 -0400 Received: from gw.goop.org ([64.81.55.164]:55401 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755249AbXINUx3 (ORCPT ); Fri, 14 Sep 2007 16:53:29 -0400 Message-ID: <46EAF4C6.8090903@goop.org> Date: Fri, 14 Sep 2007 13:53:26 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.5 (X11/20070719) MIME-Version: 1.0 To: Anthony Liguori CC: kvm-devel@lists.sourceforge.net, Avi Kivity , Ingo Molnar , Dor Laor , Rusty Russell , linux-kernel@vger.kernel.org Subject: Re: [PATCH] Refactor hypercall infrastructure References: <11897991353793-git-send-email-aliguori@us.ibm.com> In-Reply-To: <11897991353793-git-send-email-aliguori@us.ibm.com> X-Enigmail-Version: 0.95.3 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1119 Lines: 26 Anthony Liguori wrote: > This patch refactors the current hypercall infrastructure to better support live > migration and SMP. It eliminates the hypercall page by trapping the UD > exception that would occur if you used the wrong hypercall instruction for the > underlying architecture and replacing it with the right one lazily. > I guess it would be pretty rude/unlikely for these opcodes to get reused in other implementations... But couldn't you make the page trap instead, rather than relying on an instruction fault? > It also introduces the infrastructure to probe for hypercall available via > CPUID leaves 0x40000002. CPUID leaf 0x40000003 should be filled out by > userspace. > Is this compatible with Xen's (and other's) use of cpuid? That is, 0x40000000 returns a hypervisor-specific signature in e[bcd]x, and eax has the max hypervisor leaf. J - 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/