Ian Campbell wrote:
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?
On my 4.3.1 setup, I changed the above to
if (hvm) {
x_nic->nictype = LIBXL_NIC_TYPE_VIF_IOEMU;
if (l_nic->model) {
if (VIR_STRDUP(x_nic->model, l_nic->model) < 0)
return -1;
if (STREQ(l_nic->model, "netfront"))
x_nic->nictype = LIBXL_NIC_TYPE_VIF;
}
} else {
x_nic->nictype = LIBXL_NIC_TYPE_VIF;
}
which is better initialization logic IMO. If the domain is hvm, set nictype to LIBXL_NIC_TYPE_VIF_IOEMU, unless model 'netfront' is specified. This behavior is consistent with the legacy xen driver. The change seems to work fine and resolves the PXE issue Stefan noted - as long as I initialize devid in libvirt. So we'll need the above fix in libvirt, as well as a resolution to the nic devid initialization in libxl that started this thread.
Regards,
Jim It should do, in fact I thought it was the default.
How are you initialising the libxl_device_nic?
if (l_nic->model && !STREQ(l_nic->model, "netfront")) { if (VIR_STRDUP(x_nic->model, l_nic->model) < 0) return -1; x_nic->nictype = LIBXL_NIC_TYPE_VIF_IOEMU; } else { x_nic->nictype = LIBXL_NIC_TYPE_VIF; }
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)
On my 4.3.1 setup, I changed the above to if (hvm) { x_nic->nictype = LIBXL_NIC_TYPE_VIF_IOEMU; if (l_nic->model) { if (VIR_STRDUP(x_nic->model, l_nic->model) < 0) return -1; if (STREQ(l_nic->model, "netfront")) x_nic->nictype = LIBXL_NIC_TYPE_VIF; } } else { x_nic->nictype = LIBXL_NIC_TYPE_VIF; } which is better initialization logic IMO. If the domain is hvm, set nictype to LIBXL_NIC_TYPE_VIF_IOEMU, unless model 'netfront' is specified. This behavior is consistent with the legacy xen driver. The change seems to work fine and resolves the PXE issue Stefan noted - as long as I initialize devid in libvirt. So we'll need the above fix in libvirt, as well as a resolution to the nic devid initialization in libxl that started this thread. Regards, Jim