From: Christoph Lameter <clameter@sgi.com>

slub warns on this, and we're working on making kmalloc(0) return NULL. 
Let's make slab warn as well so our testers detect such callers more
rapidly.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/slab.c |    1 +
 1 files changed, 1 insertion(+)

diff -puN mm/slab.c~slab-warn-on-zero-length-allocations mm/slab.c
--- a/mm/slab.c~slab-warn-on-zero-length-allocations
+++ a/mm/slab.c
@@ -789,6 +789,7 @@ static inline struct kmem_cache *__find_
 	 */
 	BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL);
 #endif
+	WARN_ON_ONCE(size == 0);
 	while (size > csizep->cs_size)
 		csizep++;
 
_