Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:

 - A few y2038 fixes which missed the merge window while dependencies
   in NFS were being sorted out.

 - A bunch of fixes. Some minor, some not.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  MAINTAINERS: use tabs for SAFESETID
  lib/stackdepot.c: fix global out-of-bounds in stack_slabs
  mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM
  mm/vmscan.c: don't round up scan size for online memory cgroup
  lib/string.c: update match_string() doc-strings with correct behavior
  mm/memcontrol.c: lost css_put in memcg_expand_shrinker_maps()
  mm/swapfile.c: fix a comment in sys_swapon()
  scripts/get_maintainer.pl: deprioritize old Fixes: addresses
  get_maintainer: remove uses of P: for maintainer name
  selftests/vm: add missed tests in run_vmtests
  include/uapi/linux/swab.h: fix userspace breakage, use __BITS_PER_LONG for swap
  Revert "ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()"
  y2038: hide timeval/timespec/itimerval/itimerspec types
  y2038: remove unused time32 interfaces
  y2038: remove ktime to/from timespec/timeval conversion

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index ed717dd08ff3..81c69c08d1d1 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -83,15 +83,19 @@ static bool init_stack_slab(void **prealloc)
 		return true;
 	if (stack_slabs[depot_index] == NULL) {
 		stack_slabs[depot_index] = *prealloc;
+		*prealloc = NULL;
 	} else {
-		stack_slabs[depot_index + 1] = *prealloc;
+		/* If this is the last depot slab, do not touch the next one. */
+		if (depot_index + 1 < STACK_ALLOC_MAX_SLABS) {
+			stack_slabs[depot_index + 1] = *prealloc;
+			*prealloc = NULL;
+		}
 		/*
 		 * This smp_store_release pairs with smp_load_acquire() from
 		 * |next_slab_inited| above and in stack_depot_save().
 		 */
 		smp_store_release(&next_slab_inited, 1);
 	}
-	*prealloc = NULL;
 	return true;
 }