Are you enabling VFs on your system?
You should load the driver with sriov_numvfs parameter like this:
echo 4 > /sys/class/net/device name/device/sriov_numvfs
Please refer to the SR-IOV configuration guide for more details: http://www.intel.it/content/dam/www/public/us/en/documents/technology-briefs/xl710-sr-iov-config-guide-gbe-linux-brief.p…