[CentOS-virt] Xen HVM Networking in 3.10

Is anyone running lots of Xen HVM guests on a 3.10 Dom0 kernel?

We've had a few weird issues where PV guests are fine, but HVM guests are getting < 1Kb/s network throughput. The configuration on the host machine, VIF and inside the VM is fine. CPU and IO is fine too.

It only seems to affect servers with Broadcom network chipsets. Rolling back to a 3.4 Dom0 kernel fixes the problem, so its either driver (bnx2?) related or something else.

Not sure what to look at next to troubleshoot this as there are no errors anywhere, but if anyone has a test server with a brodcom NIC please can you test?

We've had this on 3 production servers now, but I cant really do any more testing on those as they are full of active VMs.

Thanks Chris