diff -Nurpd a/src/pybind/rados/rados.pyx b/src/pybind/rados/rados.pyx
--- a/src/pybind/rados/rados.pyx	2020-04-11 17:15:00.793220981 -0700
+++ b/src/pybind/rados/rados.pyx	2020-04-11 17:18:32.536405851 -0700
@@ -326,7 +326,10 @@ LIBRADOS_OPERATION_IGNORE_CACHE = _LIBRA
 LIBRADOS_OPERATION_SKIPRWLOCKS = _LIBRADOS_OPERATION_SKIPRWLOCKS
 LIBRADOS_OPERATION_IGNORE_OVERLAY = _LIBRADOS_OPERATION_IGNORE_OVERLAY
 
-LIBRADOS_ALL_NSPACES = _LIBRADOS_ALL_NSPACES.decode('utf-8')
+if isinstance(_LIBRADOS_ALL_NSPACES, str):
+    LIBRADOS_ALL_NSPACES = _LIBRADOS_ALL_NSPACES
+else:
+    LIBRADOS_ALL_NSPACES = _LIBRADOS_ALL_NSPACES.decode('utf-8')
 
 LIBRADOS_CREATE_EXCLUSIVE = _LIBRADOS_CREATE_EXCLUSIVE
 LIBRADOS_CREATE_IDEMPOTENT = _LIBRADOS_CREATE_IDEMPOTENT
diff --git a/src/pybind/rados/rados.pyx b/src/pybind/rados/rados.pyx
index fe17620..beca5ae 100644
--- a/src/pybind/rados/rados.pyx
+++ b/src/pybind/rados/rados.pyx
@@ -555,6 +555,8 @@ def decode_cstr(val, encoding="utf-8"):
     """
     if val is None:
         return None
+    if isinstance(val, str):
+        return val

     return val.decode(encoding)