Xen users - Jan 2012 - Networking Ubuntu 11.10 PV, Linux >=3.1 and Xen 4.1.2

Hi,

I am experiencing a slightly odd problem with a PV Ubuntu 11.10 guest.  
With kernel.org 3.0 kernel everything is working correctly but as soon 
as I boot with 3.1 or 3.2 then I can no longer send traffic out of my 
Ubuntu guest, however what is strange is that I can ping the Ubuntu host 
from the dom0.  Equally odd is that other domUs have no problems so it 
seems to be the specific combination of Ubuntu and the dom0 kernel 
version.  Has anyone else encountered this or am I going to be doing a 
bisect of the kernel to try and identify the patch that triggers this 
change in behaviour?

Thanks,
James

> I am experiencing a slightly odd problem with a PV Ubuntu 11.10
> guest.  With kernel.org 3.0 kernel everything is working correctly 
> but
> as soon as I boot with 3.1 or 3.2 then I can no longer send traffic
> out of my Ubuntu guest, however what is strange is that I can ping 
> the
> Ubuntu host from the dom0.  Equally odd is that other domUs have no
> problems so it seems to be the specific combination of Ubuntu and the
> dom0 kernel version.  Has anyone else encountered this or am I going
> to be doing a bisect of the kernel to try and identify the patch that
> triggers this change in behaviour?
With some further investigation this seems to relate to the network 
setup on my dom0.  If I connect to a interface+bridge it is ok but if I 
use interfaces+bond+vlan+bridge then this is where the problem arises.  
I am using gvrpcd to perform dynamic vlan membership registration from 
dom0 and on my switch it looks like this doesn''t happen with
problematic
dom0 kernels.  Since this isn''t related to Xen I''ll take it to
Linux
net.