diff --git a/src/net/http/export_test.go b/src/net/http/export_test.go
index fbed45070c..40f87dc8e9 100644
--- a/src/net/http/export_test.go
+++ b/src/net/http/export_test.go
@@ -186,3 +186,15 @@ func ExportHttp2ConfigureTransport(t *Transport) error {
 }
 
 var Export_shouldCopyHeaderOnRedirect = shouldCopyHeaderOnRedirect
+
+func (s *Server) ExportAllConnsIdle() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for c := range s.activeConn {
+		st, ok := c.curState.Load().(ConnState)
+		if !ok || st != StateIdle {
+			return false
+		}
+	}
+	return true
+}
diff --git a/src/net/http/serve_test.go b/src/net/http/serve_test.go
index f855c35822..fe63c6925f 100644
--- a/src/net/http/serve_test.go
+++ b/src/net/http/serve_test.go
@@ -4875,6 +4875,9 @@ func TestServerSetKeepAlivesEnabledClosesConns(t *testing.T) {
 	}) {
 		t.Fatalf("idle count before SetKeepAlivesEnabled called = %v; want 1", idle0)
 	}
+	if !waitCondition(2*time.Second, 10*time.Millisecond, ts.Config.ExportAllConnsIdle) {
+		t.Fatalf("test server has active conns")
+	}
 
 	ts.Config.SetKeepAlivesEnabled(false)