Re: [Qemu-devel] Re: [PATCH v2 12/15] monitor: Add basic device state visualization

[Anthony Liguori]

On 05/24/2010 03:35 PM, Jan Kiszka wrote:
> In contrast to save/loadvm, device_show does not provide a
> backward-compatible output. Not only field names can change (as a result
> of internal refactoring),

Field names could change, but that seems unlikely and unnecessary.

>   fields may even disappear,

That would break live migration.  The output of device_show when 
specifying -M pc-0.13 should always be the same.  If it's not, I believe 
that's a bug.

The output of device_show across multiple qemu versions without 
specifying a -M could certainly be different but that's to be expected 
since you have a different hardware model.

>   new ones may pop
> up. vmstate makes this transparent for reading of old states, but not
> for visualization.
>
> That said, I see no use case yet that would justify the effort for
> making state dumps as stable as vmstates.
>    

They already are.  It's just a matter of whether we declare it as such 
AFAICT.

Regards,

Anthony Liguori

> Jan
>