Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759136Ab2BONly (ORCPT ); Wed, 15 Feb 2012 08:41:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39423 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757491Ab2BONlt (ORCPT ); Wed, 15 Feb 2012 08:41:49 -0500 Message-ID: <4F3BB614.9040706@redhat.com> Date: Wed, 15 Feb 2012 15:41:40 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Jan Kiszka CC: Anthony Liguori , qemu-devel , Rob Earhart , linux-kernel , KVM list Subject: Re: [Qemu-devel] [RFC] Next gen kvm api References: <4F2AB552.2070909@redhat.com> <4F2E80A7.5040908@redhat.com> <4F3025FB.1070802@codemonkey.ws> <4F31132F.3010100@redhat.com> <4F31408F.80901@codemonkey.ws> <4F314B2A.4000709@redhat.com> <4F314EEE.8080401@siemens.com> <4F314F87.60807@codemonkey.ws> <4F315161.3050304@siemens.com> In-Reply-To: <4F315161.3050304@siemens.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1009 Lines: 29 On 02/07/2012 06:29 PM, Jan Kiszka wrote: > >>> > >> > >> Isn't there another level in between just scheduling and full syscall > >> return if the user return notifier has some real work to do? > > > > Depends on whether you're scheduling a kthread or a userspace process, no? If > > Kthreads can't return, of course. User space threads /may/ do so. And > then there needs to be a differences between host and guest in the > tracked MSRs. Right. Until we randomize kernel virtual addresses (what happened to that?) and then there will always be a difference, even if you run the same kernel in the host and guest. > I think to recall it's a question of another few hundred > cycles. Right. -- error compiling committee.c: too many arguments to function -- 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/