diff --git a/mm/rmap.c b/mm/rmap.c
index bfeffbddb71207616a7e4547d5a4dba77bb03d31..1a8bf76bfd038a7fe84fdd6b9443c4673c8ddd9f 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -80,7 +80,7 @@ static inline struct anon_vma_chain *anon_vma_chain_alloc(void)
 	return kmem_cache_alloc(anon_vma_chain_cachep, GFP_KERNEL);
 }
 
-void anon_vma_chain_free(struct anon_vma_chain *anon_vma_chain)
+static void anon_vma_chain_free(struct anon_vma_chain *anon_vma_chain)
 {
 	kmem_cache_free(anon_vma_chain_cachep, anon_vma_chain);
 }