From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754299Ab0DTJjX (ORCPT ); Tue, 20 Apr 2010 05:39:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:22231 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754277Ab0DTJjU (ORCPT ); Tue, 20 Apr 2010 05:39:20 -0400 Message-ID: <4BCD7643.4000102@redhat.com> Date: Tue, 20 Apr 2010 12:39:15 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100330 Fedora/3.0.4-1.fc12 Thunderbird/3.0.4 MIME-Version: 1.0 To: Zachary Amsden CC: Peter Zijlstra , Glauber Costa , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Jeremy Fitzhardinge , Marcelo Tosatti Subject: Re: [PATCH 1/5] Add a global synchronization point for pvclock References: <1271356648-5108-1-git-send-email-glommer@redhat.com> <1271356648-5108-2-git-send-email-glommer@redhat.com> <4BCA026D.3070309@redhat.com> <1271673975.1674.763.camel@laptop> <4BCC3520.6090305@redhat.com> <1271674273.1674.777.camel@laptop> <4BCC3654.2090600@redhat.com> <4BCCA281.6040509@redhat.com> In-Reply-To: <4BCCA281.6040509@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/19/2010 09:35 PM, Zachary Amsden wrote: >>>> Sockets and boards too? (IOW, how reliable is TSC_RELIABLE)? >>> Not sure, IIRC we clear that when the TSC sync test fails, eg when we >>> mark the tsc clocksource unusable. >> >> Worrying. By the time we detect this the guest may already have >> gotten confused by clocks going backwards. > > > Upstream, we are marking the TSC unstable preemptively when hardware > which will eventually sync test is detected, so this should be fine. ENOPARSE? -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.