From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zachary Amsden Subject: Re: 2.6.35-rc1 regression with pvclock and smp guests Date: Mon, 11 Oct 2010 10:47:16 -1000 Message-ID: <4CB377D4.2020401@redhat.com> References: <4CA4DBC8.6070606@xutrox.com> <20100930190507.GA1111@amt.cnet> <4CA51715.1070507@msgid.tls.msk.ru> <4CA51847.5060208@msgid.tls.msk.ru> <4CA6C4BB.5020004@redhat.com> <4CA6E0BF.90605@msgid.tls.msk.ru> <4CA75969.1080405@xutrox.com> <4CA7C34C.4040000@redhat.com> <4CAE6203.6040902@xutrox.com> <4CAE862F.10904@redhat.com> <20101008220600.GA9430@amt.cnet> <4CAFC11B.8010603@xutrox.com> <4CAFD327.3030608@redhat.com> <4CB00BC8.7090705@msgid.tls.msk.ru> <4CB02F08.3090207@xutrox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Michael Tokarev , kvm@vger.kernel.org, Marcelo Tosatti , Avi Kivity , Glauber Costa , Andre Przywara To: Arjan Koers <0h61vkll2ly8@xutrox.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:62840 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755126Ab0JKUrZ (ORCPT ); Mon, 11 Oct 2010 16:47:25 -0400 In-Reply-To: <4CB02F08.3090207@xutrox.com> Sender: kvm-owner@vger.kernel.org List-ID: On 10/08/2010 10:59 PM, Arjan Koers wrote: > On 2010-10-09 08:29, Michael Tokarev wrote: > ... > >> The result is that no released linux kernel boots >> in smp in kvm, which is a linux virtual machine. >> That's irony, isn't it? >> >> I wonder how distributions (which are almost all based >> on 2.6.32 nowadays) will deal with the issue.. ;) >> > It looks like Debian solved it on their 2.6.32 guest by > reverting the commit that makes it hang: > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=588426 > That's not a wise choice, the commit is needed to prevent clocks going backwards. It then caused some fallout issues with clobbers, which I believe hpa fixed, but there were several rounds of it. Glauber, perhaps, has a better idea of what patches are needed for the host side kvmclock. I've mostly been working on the server side. To solve the wider range of problems, distributions converging on 2.6.32 will need all of the fixes backported, both server and host.