2 files changed, 4 insertions, 1 deletions

diff --git a/include/linux/mempool.h b/include/linux/mempool.h
index b19b3023c880..69b6951e8fd2 100644
--- a/include/linux/mempool.h
+++ b/include/linux/mempool.h
@@ -36,7 +36,8 @@ extern void mempool_free(void *element, mempool_t *pool);
 
 /*
  * A mempool_alloc_t and mempool_free_t that get the memory from
- * a slab that is passed in through pool_data.
+ * a slab cache that is passed in through pool_data.
+ * Note: the slab cache may not have a ctor function.
  */
 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
 void mempool_free_slab(void *element, void *pool_data);
diff --git a/mm/mempool.c b/mm/mempool.c
index 949970db2874..b60fb85526ed 100644
--- a/mm/mempool.c
+++ b/mm/mempool.c
@@ -15,6 +15,7 @@
 #include <linux/mempool.h>
 #include <linux/blkdev.h>
 #include <linux/writeback.h>
+#include "slab.h"
 
 static void add_element(mempool_t *pool, void *element)
 {
@@ -334,6 +335,7 @@ EXPORT_SYMBOL(mempool_free);
 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data)
 {
         struct kmem_cache *mem = pool_data;
+        VM_BUG_ON(mem->ctor);
         return kmem_cache_alloc(mem, gfp_mask);
 }
 EXPORT_SYMBOL(mempool_alloc_slab);