Re: [Qemu-devel] [PATCH] target-ppc: Add @cpu_dt_id into migration stream

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 03/27/2014 11:57 PM, Peter Maydell wrote:
> On 27 March 2014 12:49, Alexey Kardashevskiy <aik@ozlabs.ru> wrote:
>> On 03/27/2014 11:37 PM, Andreas Färber wrote:
>>> Am 27.03.2014 03:41, schrieb Alexey Kardashevskiy:
>>>> This should prevent the destination guest from misbehaving when
>>>> the threads number is different in "-smp" command.
>>>
>>> Sorry, I don't understand. When migrating, surely -smp needs to be the
>>> same on source and destination, so how can they differ?
>>
>>
>> The idea is that "-smp" does not migrate and if we run source and
>> destination guests with different numbers in -smp, we end up with weird
>> machine
> 
> Yes, so don't do that. As I understand it:
>  (1) if you don't run QEMU with the exact same command line
>      and config at both ends then migration won't work
>  (2) we don't guarantee to detect and cleanly fail if you
>      don't do (1)
> 
> It would probably be nice if we did detect config mismatches,

Yep, we do not send the device tree (as libvirt does). Pure command line
matching won't work.

> but that seems to me like a problem we should be addressing
> more globally than just for one particular config item for
> one particular target...

This is lot bigger that the issue I am trying to solve by this patch...
Still nack?


-- 
Alexey