A vagrant config and accompanying scripts are available at https://github.com/multipath-tcp/mptcp-vagrant. It has been tested on Ubuntu Linux hosts and should be a very easy way to test MPTCP once you have installed Vagrant and Virtualbox as it only takes a couple of vagrant commands to get going.
Companion scripts also help in kernel development:
- compile your kernel on the host and install it in the guest
- select which kernel to boot in the guest
- enable and access the guest's netconsole
Take a look at the README for further details.