diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 437aaa8174..750abe37d4 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -515,13 +515,16 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
             return ret;
         }
     } else {
-        /* FIXME Order */
-        if (l2_offset)
-            qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+        /* First allocate a new L2 table (and do COW if needed) */
         ret = l2_allocate(bs, l1_index, &l2_table);
         if (ret < 0) {
             return ret;
         }
+
+        /* Then decrease the refcount of the old table */
+        if (l2_offset) {
+            qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+        }
         l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
     }