diff --git a/commit-graph.c b/commit-graph.c
index 702ba9731b..a0bca248ac 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -2610,7 +2610,7 @@ int write_commit_graph(struct odb_source *source,
 
 	g = prepare_commit_graph(ctx.r);
 	for (struct commit_graph *chain = g; chain; chain = chain->base_graph)
-		g->topo_levels = &topo_levels;
+		chain->topo_levels = &topo_levels;
 
 	if (flags & COMMIT_GRAPH_WRITE_BLOOM_FILTERS)
 		ctx.changed_paths = 1;
diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh
index b41331e3dd..9e5ab7dbd0 100755
--- a/t/t5324-split-commit-graph.sh
+++ b/t/t5324-split-commit-graph.sh
@@ -718,7 +718,7 @@ test_expect_success 'write generation data chunk when commit-graph chain is repl
 	)
 '
 
-test_expect_failure 'incremental write reads topo levels from all layers' '
+test_expect_success 'incremental write reads topo levels from all layers' '
 	git init topo-from-lower &&
 	(
 		cd topo-from-lower &&