Merge branch 'tcp-smc-rendezvous'

Ursula Braun says:

====================
TCP experimental option for SMC rendezvous

SMC-capability is to be negotiated with a TCP experimental option.
As requested during code review of our previous approach using
netfilter hooks, here's a new version. It touches tcp-code in the
first patch and exploits the new tcp flag in the smc-code.

Changelog:

V3:
* move include for linux/unaligned/access_ok.h to tcp_input.c

V2:
* switch to current jump labels API
* remove static key checking in smc_set_capability()
  (comment from Eric Dumazet)
* use inet_request_sock parameter for smc_set_option_cond()
* smc_listen_work(): replace local variable lgr_lock_taken by new labels
                     and separate this change into a prerequisite first
                     patch
====================

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