Merge branch 'ibmvnic-Bug-fixes-for-queue-descriptor-processing'

Thomas Falcon says:

====================
ibmvnic: Bug fixes for queue descriptor processing

This series resolves a few issues in the ibmvnic driver's
RX buffer and TX completion processing. The first patch
includes memory barriers to synchronize queue descriptor
reads. The second patch fixes a memory leak that could
occur if the device returns a TX completion with an error
code in the descriptor, in which case the respective socket
buffer and other relevant data structures may not be freed
or updated properly.

v3: Correct length of Fixes tags, requested by Jakub Kicinski

v2: Provide more detailed comments explaining specifically what
    reads are being ordered, suggested by Michael Ellerman
====================

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