diff --git a/qemu/translate-all.c b/qemu/translate-all.c
index b599ee3d..a62e3b57 100644
--- a/qemu/translate-all.c
+++ b/qemu/translate-all.c
@@ -722,11 +722,11 @@ static inline void *alloc_code_gen_buffer(struct uc_struct *uc)
         case 1:
             if (!cross_256mb(buf2, size)) {
                 /* Success!  Use the new buffer.  */
-                munmap(buf, size);
+                munmap(buf, size + qemu_real_host_page_size);
                 break;
             }
             /* Failure.  Work with what we had.  */
-            munmap(buf2, size);
+            munmap(buf2, size + qemu_real_host_page_size);
             /* fallthru */
         default:
             /* Split the original buffer.  Free the smaller half.  */