Pull pidfd fixes from Christian Brauner:
"This makes setting the exit_state in exit_notify() consistent after
fixing the pidfd polling race pre-rc1. Related to the race fix, this
adds a WARN_ON() to do_notify_pidfd() to catch any future exit_state
races.
Last, this removes an obsolete comment from the pidfd tests"
* tag 'for-linus-
20190730' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
exit: make setting exit_state consistent
pidfd: Add warning if exit_state is 0 during notification
pidfd: remove obsolete comments from test