Merge branch 'xdp-bpf-fixes'

John Fastabend says:

====================
net: Fixes for XDP/BPF

The following fixes, UAPI updates, and small improvement,

i. XDP needs to be called inside RCU with preempt disabled.

ii. Not strictly a bug fix but we have an attach command in the
sockmap UAPI already to avoid having a single kernel released with
only the attach and not the detach I'm pushing this into net branch.
Its early in the RC cycle so I think this is OK (not ideal but better
than supporting a UAPI with a missing detach forever).

iii. Final patch replace cpu_relax with cond_resched in devmap.
====================

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