Merge branch 'mlx4-fixes'

Tariq Toukan says:

====================
Safe flow for mlx4_en configuration change

This patchset improves the mlx4_en driver resiliency, especially on
systems with low memory.  Upon a configuration change that requires
the allocation of new resources, we first try to allocate, prior to
destroying the current ones.  Once it is successfully done,
we release the old resources and attach the new ones.  Otherwise, we
stay with a functioning interface having the same old configuration.

This improvement became of greater significance after removing the use
of vmap.
====================

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