Merge branch 'stacking-fixes' (vfs stacking fixes from Jann)

Merge filesystem stacking fixes from Jann Horn.

* emailed patches from Jann Horn <jannh@google.com>:
  sched: panic on corrupted stack end
  ecryptfs: forbid opening files without mmap handler
  proc: prevent stacking filesystems on top
static inline bool sched_debug(void)
{
	return sched_debug_enabled;
}

static inline bool sched_debug(void)
{
	return sched_debug_enabled;
}
