From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162012AbWKVJLN (ORCPT ); Wed, 22 Nov 2006 04:11:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1162011AbWKVJLN (ORCPT ); Wed, 22 Nov 2006 04:11:13 -0500 Received: from gw.goop.org ([64.81.55.164]:3472 "EHLO mail.goop.org") by vger.kernel.org with ESMTP id S1162012AbWKVJLL (ORCPT ); Wed, 22 Nov 2006 04:11:11 -0500 Message-ID: <45641422.5090601@goop.org> Date: Wed, 22 Nov 2006 01:10:58 -0800 From: Jeremy Fitzhardinge User-Agent: Thunderbird 1.5.0.8 (X11/20061107) MIME-Version: 1.0 To: Avi Kivity CC: "H. Peter Anvin" , Arnd Bergmann , kvm-devel@lists.sourceforge.net, akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: [kvm-devel] [PATCH] KVM: Avoid using vmx instruction directly References: <4563667B.2060209@goop.org> <4563F158.3060209@qumranet.com> In-Reply-To: <4563F158.3060209@qumranet.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Avi Kivity wrote: > Very interesting. > > Will it work on load/store architectures? Since all memory access is > through a register, won't the constraint generate a useless register > load (and a use of the variable)? Don't know; interesting question. It might be worth lobbying the gcc folks for an asm() constraint which means "pretend this is being read/written, but don't generate any code, and raise an error if the asm actually tries to use it". Or perhaps there's some way to do that already. On the other hand, load/store archs tend to have lots of registers anyway, so maybe it isn't a big deal. J