diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3b3e134..3f3ccfe 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -235,6 +235,7 @@
 struct page *vmalloc_to_page(const void *addr);
 unsigned long vmalloc_to_pfn(const void *addr);
 
+#ifdef CONFIG_MMU
 /* Determine if an address is within the vmalloc range */
 static inline int is_vmalloc_addr(const void *x)
 {
@@ -242,6 +243,7 @@
 
 	return addr >= VMALLOC_START && addr < VMALLOC_END;
 }
+#endif
 
 static inline struct page *compound_head(struct page *page)
 {