I think you intended to add Andrew Turner instead of me.

I agree with Gleb. I have noted in D539 that LAGG_PROTO_ETHERCHANNEL should be kept for compatibility.

As fec is just an alias to loadbalance I would remove it only from share/man/man4/lagg.4 and any other documentation. This allows ifconfig to keep working and the supporting code in sys/net/if_lagg.c is rather trivial.

It should be able to be achieved with something like this (untested).

Also, I realise the functions are named by the Murmur author but having a x86 named function in the MI pf code may be confusing.

murmur_hash.c is missing a licence block, it looks like it may be MIT.