slab: fix for_each_kmem_cache_node()

Fix a bug (discovered with kmemcheck) in for_each_kmem_cache_node().  The
for loop reads the array "node" before verifying that the index is within
the range.  This results in kmemcheck warning.

Signed-off-by: Mikulas Patocka <[email protected]>
Reviewed-by: Pekka Enberg <[email protected]>
Acked-by: Christoph Lameter <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/slab.h b/mm/slab.h
index 026e7c393f0be3ec2a7a66bb835bf5d69d8006d6..6599f2084e80ef4e4e4dcd62abd7078b42efe216 100644 (file)
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -338,8 +338,8 @@ static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
  * a kmem_cache_node structure allocated (which is true for all online nodes)
  */
 #define for_each_kmem_cache_node(__s, __node, __n) \
-       for (__node = 0; __n = get_node(__s, __node), __node < nr_node_ids; __node++) \
-                if (__n)
+       for (__node = 0; __node < nr_node_ids; __node++) \
+                if ((__n = get_node(__s, __node)))
 
 #endif