Merge branch 'rprpc-2nd-rewrite-part-1'

Merge branch 'rprpc-2nd-rewrite-part-1'

David Howells says:

====================
RxRPC: 2nd rewrite part 1

Okay, I'm in the process of rewriting the RxRPC rewrite.  The primary aim of
this second rewrite is to strictly control the number of active connections we
know about and to get rid of connections we don't need much more quickly.

On top of this, there are fixes to the protocol handling which will all occur
in later parts.

Here's the first set of patches from the second go, aimed at net-next.  These
are all fixes and cleanups preparatory to the main event.

Notable parts of this set include:

 (1) A fix for the AFS filesystem to wait for outstanding calls to complete
     before closing the RxRPC socket.

 (2) Differentiation of local and remote abort codes.  At a future point
     userspace will get to see this via control message data on recvmsg().

 (3) Absorb the rxkad module into the af_rxrpc module to prevent a dependency
     loop.

 (4) Create a null security module and unconditionalise calls into the
     security module that's in force (there will always be a security module
     applied to a connection, even if it's just the null one).
====================

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