diff --git a/mm/mremap.c b/mm/mremap.c
index 238c169dc969452db1ae3fa42149e51e7c9f948f..2945a4986e941a0f6e7752b1d44a23bbaa77513e 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -202,6 +202,9 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
 	unsigned long mmun_start;	/* For mmu_notifiers */
 	unsigned long mmun_end;		/* For mmu_notifiers */
 
+	if (!len)
+		return 0;
+
 	old_end = old_addr + len;
 	flush_cache_range(vma, old_addr, old_end);