From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753674Ab0HXA4p (ORCPT ); Mon, 23 Aug 2010 20:56:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:28413 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751478Ab0HXA4n (ORCPT ); Mon, 23 Aug 2010 20:56:43 -0400 Message-ID: <4C7318C0.3030706@redhat.com> Date: Mon, 23 Aug 2010 14:56:32 -1000 From: Zachary Amsden User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100621 Fedora/3.0.5-1.fc13 Thunderbird/3.0.5 MIME-Version: 1.0 To: Glauber Costa CC: kvm@vger.kernel.org, Avi Kivity , Marcelo Tosatti , Thomas Gleixner , John Stultz , linux-kernel@vger.kernel.org Subject: Re: [KVM timekeeping 08/35] Warn about unstable TSC References: <1282291669-25709-1-git-send-email-zamsden@redhat.com> <1282291669-25709-9-git-send-email-zamsden@redhat.com> <20100820172824.GD2937@mothafucka.localdomain> In-Reply-To: <20100820172824.GD2937@mothafucka.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/20/2010 07:28 AM, Glauber Costa wrote: > On Thu, Aug 19, 2010 at 10:07:22PM -1000, Zachary Amsden wrote: > >> If creating an SMP guest with unstable host TSC, issue a warning >> >> Signed-off-by: Zachary Amsden >> > Ok, I am not sure I agree 100 % this is needed. > I believe we should try to communicate this kind of thing to the guest, > not the host, and through cpuid. > > Passing through tsc flags to the guest should maybe be enough? > I found a better way to deal with this later in the series... the theory being if the full series doesn't get backported to supported releases, at least we'll get a warning.