diff --git a/gio/tests/converter-stream.c b/gio/tests/converter-stream.c
index 6befa274c..8c4731590 100644
--- a/gio/tests/converter-stream.c
+++ b/gio/tests/converter-stream.c
@@ -1022,10 +1022,10 @@ test_converter_pollable (void)
 	}
 
       /* Wait a few ticks to check for the pipe to propagate the
-       * write. Finesses the race condition in the following test,
-       * where is_readable fails because the write hasn't propagated,
-       * but the read then succeeds because it has. */
-      g_usleep (80L);
+       * write. We can’t wait on a GSource as that might affect the stream under
+       * test, so just poll. */
+      while (!g_pollable_input_stream_is_readable (pollable_in))
+        g_usleep (80L);
 
       is_readable = g_pollable_input_stream_is_readable (pollable_in);
       res = g_pollable_input_stream_read_nonblocking (pollable_in,