Derive link type from PF if the interface name is not available

In case a workload is already consuming a VF and
sriov-device-plugin is restarted,
when this selector is specified, the device plugin will fail
to get the VF link type since getting this information
requires the VF netdev. The netdev does not exist in the host namespace
as its assigned to pod. this causes sriov-network-device-plugin to fail
adding this VF to resource pool,
causing it to report the wrong number of resources.

To fix this, derive the link type of the device from its PF,
if the netdev itself is not available.

Signed-off-by: amaslennikov <amaslennikov@nvidia.com>

pkg/devices/gen_net.go

@@ -45,7 +45,7 @@ func NewGenNetDevice(deviceID string, dt types.DeviceType, isRdma bool) (*GenNet
 	var funcID int
 	var err error
 
-	//nolint: exhaustive
+	// nolint: exhaustive
 	switch dt {
 	case types.NetDeviceType:
 		if pfName, err = utils.GetPfName(deviceID); err != nil {
@@ -82,8 +82,13 @@ func NewGenNetDevice(deviceID string, dt types.DeviceType, isRdma bool) (*GenNet
 	}
 
 	linkType := ""
-	if len(ifName) > 0 {
-		la, err := utils.GetNetlinkProvider().GetLinkAttrs(ifName)
+	linkTypeProviderDevice := ifName
+	// If interface name is not available, derive link type from PF
+	if linkTypeProviderDevice == "" {
+		linkTypeProviderDevice = pfName
+	}
+	if linkTypeProviderDevice != "" {
+		la, err := utils.GetNetlinkProvider().GetLinkAttrs(linkTypeProviderDevice)
 		if err != nil {
 			return nil, err
 		}