I know this is an old thread but...
Had the same problem so I opened a TAC case. The engineer said this is a bug that is only internally visible to Cisco at this time. The only condition they have for it is that it appears on the 9400's with SUP's. The TAC-recommended fix is to reload the switch. I was unable to ascertain from TAC if/when there is a fix for it or what the cause is.