Re: [libvirt] [Xen-devel] Setting devid for emulated NICs (Xen 4.3.1 / libvirt 1.2.0) using libxl driver
On Thu, 2013-12-19 at 11:39 -0700, Jim Fehlig wrote:
Stefan Bader wrote:
> Oh, just while talking about setdefault. Jim, this is one of the odd things when
> moving from xm to xl stack from libvirt: libvirt defaults to the netfront NIC
> when no model is specified and sets the type. The libxl setdefault function sets
> the model to rtl8139 but leaves the type untouched.
The xend toolstack always creates both emulated and vif devices unless
'type=netfront' is explicitly specified. As you say, the guest gets to
choose what to do with them. E.g. PXE boot using the emulated device,
or have the driver for the PV device unplug the emulated one. I don't
think libxl supports this right?
It should do, in fact I thought it was the default.
How are you initialising the libxl_device_nic? Type == VIF_IOEMU (which
is the default for a VIF on an HVM guest) means both emulated and pv.
(there were bugs in the semantics here in very early versions of libxl,
but I thought they were fixed even before 4.2)
I don't think there is an option to have just the emulated device --
there is always a PV VIF there even if the guest doesn't use it.
Ian.