From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matt Mullins <mmullins@mmlx.us>
Subject: Re: Live migration locks up 3.2 guests in do_timer(ticks ~ 500000)
Date: Tue, 11 Nov 2014 11:57:03 -0800
Message-ID: <20141111195703.GF29098@hydra.tuxags.com>
References: <20140908055416.GE23305@hydra.tuxags.com>
 <540D663E.2070905@redhat.com>
 <20140908155642.GF23305@hydra.tuxags.com>
 <540DD6E6.70409@redhat.com>
 <20140910065349.GM23305@hydra.tuxags.com>
 <20140915181441.GN23305@hydra.tuxags.com>
 <5417F801.20408@redhat.com>
 <20141027184216.GA29098@hydra.tuxags.com>
 <544F5C0A.1040504@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: kvm@vger.kernel.org
To: Paolo Bonzini <pbonzini@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from hydra.tuxags.com ([64.13.172.54]:35663 "EHLO mail.tuxags.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1750716AbaKKUEs (ORCPT <rfc822;kvm@vger.kernel.org>);
	Tue, 11 Nov 2014 15:04:48 -0500
Content-Disposition: inline
In-Reply-To: <544F5C0A.1040504@redhat.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On Tue, Oct 28, 2014 at 10:04:10AM +0100, Paolo Bonzini wrote:
> can you test using QEMU from git://git.qemu-project.org/qemu.git?

That seems to work great, yes.

Looking through the commit history, I see:
      kvmclock: Ensure time in migration never goes backward
      kvmclock: Ensure proper env->tsc value for kvmclock_current_nsec calculation

Assuming those are the right fixes for this issue, are they suitable to request
backported to distros' qemu 2.0 branches?  The merge commit for them seemed to
indicate they were problematic at first.

On second thought - I found the qemu-devel threads about reverting them in the
2.1 timeframe, so I'm going to do a little more research before I start trying
to suggest how to fix for existing install-base.