Re: [Qemu-devel] [PATCH 3/3] virtio-gpu: Warn if UI config will disable virgl

[Cole Robinson <crobinso@redhat.com>]

On 05/20/2016 01:53 AM, Gerd Hoffmann wrote:
> On Mi, 2016-05-18 at 12:40 -0400, Cole Robinson wrote:
>> Give users a hint if their config is wrong.
>>
>> Signed-off-by: Cole Robinson <crobinso@redhat.com>
>> ---
>> If virgl support is built into qemu, virgl=on is the default, so this
>> could be noisy in cases where people don't even care about virgl. So
>> I won't object if this is dropped.
> 
> Yes, it's enabled by default, so users have to flip one switch only
> (-spice gl=on) to enable 3d, not two.  So warning here is a bad thing
> IMO.
> 
> We could turn the virgl switch into tristate (OnOffAuto), have it
> default to Auto, then fail (not warn) in case it is set to On without 3d
> support being available.
> 

Property settings are part of the migration format, right? Is there an easy
way to change the 'virgl' property like that in a backwards compatible way? Or
decouple the command line handling from the Property value?

Thanks,
Cole