Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2021-12-31

We've added 2 non-merge commits during the last 14 day(s) which contain
a total of 2 files changed, 3 insertions(+), 3 deletions(-).

The main changes are:

1) Revert of an earlier attempt to fix xsk's poll() behavior where it
   turned out that the fix for a rare problem made it much worse in
   general, from Magnus Karlsson. (Fyi, Magnus mentioned that a proper
   fix is coming early next year, so the revert is mainly to avoid
   slipping the behavior into 5.16.)

2) Minor misc spell fix in BPF selftests, from Colin Ian King.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf, selftests: Fix spelling mistake "tained" -> "tainted"
  Revert "xsk: Do not sleep in poll() when need_wakeup set"
====================

Link: https://lore.kernel.org/r/20211231160050.16105-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>