I will be implementing a test in DTS for RSS Key Update.
http://doc.dpdk.org/guides/nics/features.html#rss-key-update

To my understanding, this feature will test the ability to configure the hash key of the ports. If that is incorrect, please let me know. 

Configure the port RSS hash key in testpmd and check if the new key will be kept. Test configure the hash key that is longer than the max length and shorter than the max length.

Then start sending in packets with different source and destination IP addresses. Ensure the ports are still able to calculate the hash value from the incoming packets. 

Please let me know if there is anything else need to be tested,