diff --git a/doc/requirements.txt b/doc/requirements.txt
index 0673b3d..895522d 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,6 +1,3 @@
-# The order of packages is significant, because pip processes them in the order
-# of appearance. Changing the order has an impact on the overall integration
-# process, which may cause wedges in the gate later.
 openstackdocstheme>=2.2.1 # Apache-2.0
 reno>=3.1.0 # Apache-2.0
-sphinx>=2.0.0,!=2.1.0 # BSD
+sphinx>=2.0.0 # BSD
diff --git a/requirements.txt b/requirements.txt
index 7deef88..57cf689 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1 +1 @@
-pbr!=2.1.0,>=2.0.0 # Apache-2.0
+pbr>=2.0.0 # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 5d08445..962d138 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,4 +1,4 @@
-coverage!=4.4,>=4.0 # Apache-2.0
+coverage>=4.0 # Apache-2.0
 stestr>=2.0.0 # Apache-2.0
 # sphinx is needed for testing the sphinxext module
-sphinx>=2.0.0,!=2.1.0 # BSD
+sphinx>=2.0.0 # BSD