diff --git a/gasket_sysfs.c b/gasket_sysfs.c
index e3d7706..dd4d3aa 100644
--- a/gasket_sysfs.c
+++ b/gasket_sysfs.c
@@ -194,7 +194,7 @@ int gasket_sysfs_create_mapping(
 			"0x%p.", device);
 		put_mapping(mapping);
 		mutex_unlock(&function_mutex);
-		return -EINVAL;
+		return -EBUSY;
 	}
 
 	/* Find the first empty entry in the array. */