diff --git a/tox.ini b/tox.ini
index 32319b2735..35e22da9ae 100644
--- a/tox.ini
+++ b/tox.ini
@@ -23,7 +23,7 @@ commands = {posargs}
 [testenv:cover]
 setenv = VIRTUAL_ENV={envdir}
 commands =
-  python setup.py testr --coverage
+  python setup.py testr --coverage --testr-args='{posargs}'
 
 [testenv:docs]
 deps = -r{toxinidir}/requirements.txt