From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: Buggy interaction of live migration and p2m updates
Date: Mon, 1 Dec 2014 14:38:23 +0000
Message-ID: <547C7D5F.3090009@citrix.com>
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To: Andrew Cooper <andrew.cooper3@citrix.com>, Xen-devel List <xen-devel@lists.xen.org>
Cc: Juergen Gross <JGross@suse.com>, Wei Liu <wei.liu2@citrix.com>, Ian Campbell <Ian.Campbell@citrix.com>, Tim Deegan <tim@xen.org>, Ian Jackson <Ian.Jackson@eu.citrix.com>, David Vrabel <david.vrabel@citrix.com>, Jan Beulich <JBeulich@suse.com>, Shriram Rajagopalan <rshriram@cs.ubc.ca>, Hongyang Yang <yanghy@cn.fujitsu.com>
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On 20/11/14 18:28, Andrew Cooper wrote:
> 
> 1) Freeze the guests p2m during live migrate
> 2) Deep p2m dirty tracking
> 3) Eagerly check for p2m structure changes.
> 4) Request p2m structure change updates from the guest

> Proposed solution:  A combination of 2, 3 and 4.

Option 5: don't change anything.  PV guests and toolstacks are
well-behaved and ensure that p2m updates do not occur during domain save.

We have never supported migrating non-cooperative PV guests.

I'd be more interested fixing this for HVM guests.

David