diff --git a/mm/mremap.c b/mm/mremap.c
index 8005d0b2b843..8ce1b7632fbb 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -246,6 +246,9 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
 	struct mmu_notifier_range range;
 	pmd_t *old_pmd, *new_pmd;
 
+	if (!len)
+		return 0;
+
 	old_end = old_addr + len;
 	flush_cache_range(vma, old_addr, old_end);