This update has been unpushed.
I think we should provide a better plugin configuration in /etc/mptcpd/mptcpd.conf .
w.r.t. tc:
# make -C tools/testing/selftests/ TARGETS=tc-testing run_tests on latest net-next tree
worked fine.
proved to fix https://bugzilla.redhat.com/show_bug.cgi?id=1816765