diff --git a/mm/nommu.c b/mm/nommu.c
index 1f60194..2b16b00 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -262,6 +262,14 @@
 }
 
 /*
+ * Implement a stub for vmalloc_sync_all() if the architecture chose not to
+ * have one.
+ */
+void  __attribute__((weak)) vmalloc_sync_all(void)
+{
+}
+
+/*
  *  sys_brk() for the most part doesn't need the global kernel
  *  lock, except when an application is doing something nasty
  *  like trying to un-brk an area that has already been mapped