Merge branch 'smc-fixes'

Ursula Braun says:

====================
net/smc: fixes 2018-07-18

here are small fixes for SMC: The first patch speeds up unidirectional
traffic, the second patch increases security, and the third patch
fixes a problem for fallback cases.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>