Re: Xen 4.3 development update

[Anthony PERARD <anthony.perard@citrix.com>]

On 13/05/13 16:15, Ian Campbell wrote:
> On Mon, 2013-05-13 at 16:08 +0100, George Dunlap wrote:
>> OK -- so you're saying that qxl actually *does* work, but just in a 
>> limited fashion: as long as the guest only access the standard vga 
>> interface, then you can connect over spice; but if the guest uses the 
>> special qxl interface, then it crashes.

Of what I can understand of the few tests I've run, and what it said in
this thread, qxl *does not* work. The standard vga is, IMHO, for
compatibility with a guest that does not have qxl driver or early at
boot when a qxl driver can not be started.

QXL is not require in order to use SPICE. So there is no benefit for now
of having "vga = qxl" in the guest config file.

>> We don't really use qxl, so that wasn't clear at first; we thought that 
>> you were saying it didn't work at all.
> 
> yes, it's all much clearer to me now, thanks Fabio.
> 
>> If it didn't work at all, then there's no point exposing functionality 
>> that can't actually work.  But since there is new functionality (albeit 
>> limited) exposed by the "qxl" option, we should keep it in.
>>
>> But we do need to make sure to set people's expectations properly -- our 
>> release notes will have to advertize "partial qxl support".
> 
> Fabio, Is there some mechanism by which we can disable the magic qxl
> interface and only leave qxl vga enabled, i.e. to workaround the
> unfortunate crash?

I believe we would have to remove "vga = qxl" somehow, like adding an
error "QXL not supported for now", unless we are able to find the issue
between Xen and QXL.

-- 
Anthony PERARD