Re: VM Migration on ARM

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 20/03/15 13:17, Vijay Kilari wrote:
> Hi Andrew,
>
> On Wed, Mar 11, 2015 at 4:21 PM, Andrew Cooper
> <andrew.cooper3@citrix.com>  wrote:
>> On 11/03/15 05:32, Vijay Kilari wrote:
>>> Hi Andrew,
>>>
>>>      From Ian & Stefano, I came to know that you have introduced
>>> Migration framework v2
>>> under below patch series
>>>
>>> http://marc.info/?l=xen-devel&m=141036915311145
>>>
>>> I have few queries:
>>>
>>> 1) Is there any plans/timeline to support for ARM32/ARM64?.
>> I will not personally be doing any ARM migration support, not even as
>> part of getting migration v2 accepted upstream.
>>
>>> 2) Also does the Domain Image format specification for ARM is complete?
>> The spec has certain sentinel values for ARM already where it made sense
>> to just include them while writing.
>>
>> It has no specific thought to ARM migration, but an ARM virtual machine
>> is exactly like an x86 HVM domain (from the toolstacks point of view),
>> other than the Qemu record.  With any luck, no new additions to the spec
>> will be needed, but the spec is trivially extendible if required.
> IMO, ARM uses PVH domain.
> Can you please let me know how to use your patches, I mean xl/xc commands
> to do migration (non-live/live) using your patches.
> Any debugging and testing support information would be helpful.

Hi - apologises for the late reply.  I have been on holiday.

The patches series as available does make `xl save/restore/migrate` 
work, although the error handling leaves a lot to be desired.

We (XenServer) are in the process of attempting to get everything 
upstream.  The libxc side of things is definitely working and already 
shipped in XenServer 6.5 (We absolutely needed to support migrating 
between 32 and 64bit toolstacks, which was the primary reason for the 
rewrite).

What sort of timescale are you looking for on this?  I hope to have a 
new series posted soon, now that the datacopier subseries has been accepted.

~Andrew