diff --git a/requirements.txt b/requirements.txt
index 88c9084..9bb9854 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-pbr>=2.0.0 # Apache-2.0
+pbr!=2.1.0,>=2.0.0 # Apache-2.0
 oslo.utils>=3.20.0 # Apache-2.0
 oslo.i18n>=2.1.0 # Apache-2.0
 oslo.serialization>=1.10.0 # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 1848573..dacd1a0 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,9 +4,9 @@
 
 hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
-coverage>=4.0 # Apache-2.0
+coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=0.0.18 # Apache-2.0/BSD
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
 oslosphinx>=4.7.0 # Apache-2.0
 oslotest>=1.10.0 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD