slub: Disable interrupts in free_debug processing

We will be calling free_debug_processing with interrupts disabled
in some case when the later patches are applied. Some of the
functions called by free_debug_processing expect interrupts to be
off.
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

mm/slub.c

@@ -1040,6 +1040,10 @@ static noinline int alloc_debug_processing(struct kmem_cache *s, struct page *pa
 static noinline int free_debug_processing(struct kmem_cache *s,
 		 struct page *page, void *object, unsigned long addr)
 {
+	unsigned long flags;
+	int rc = 0;
+
+	local_irq_save(flags);
 	slab_lock(page);
 
 	if (!check_slab(s, page))
@@ -1056,7 +1060,7 @@ static noinline int free_debug_processing(struct kmem_cache *s,
 	}
 
 	if (!check_object(s, page, object, SLUB_RED_ACTIVE))
-		return 0;
+		goto out;
 
 	if (unlikely(s != page->slab)) {
 		if (!PageSlab(page)) {
@@ -1077,13 +1081,15 @@ static noinline int free_debug_processing(struct kmem_cache *s,
 		set_track(s, object, TRACK_FREE, addr);
 	trace(s, page, object, 0);
 	init_object(s, object, SLUB_RED_INACTIVE);
+	rc = 1;
+out:
 	slab_unlock(page);
-	return 1;
+	local_irq_restore(flags);
+	return rc;
 
 fail:
 	slab_fix(s, "Object at 0x%p not freed", object);
-	slab_unlock(page);
-	return 0;
+	goto out;
 }
 
 static int __init setup_slub_debug(char *str)