diff --git a/mercurial/exchange.py b/mercurial/exchange.py
--- a/mercurial/exchange.py
+++ b/mercurial/exchange.py
@@ -1582,6 +1582,7 @@ def getbundlechunks(repo, source, heads=
 
     Returns an iterator over raw chunks (of varying sizes).
     """
+    kwargs = pycompat.byteskwargs(kwargs)
     usebundle2 = bundle2requested(bundlecaps)
     # bundle10 case
     if not usebundle2:
diff --git a/mercurial/templater.py b/mercurial/templater.py
--- a/mercurial/templater.py
+++ b/mercurial/templater.py
@@ -1303,6 +1303,7 @@ class templater(object):
         return stringify(self('', **mapping))
 
     def __call__(self, t, **mapping):
+        mapping = pycompat.byteskwargs(mapping)
         ttype = t in self.map and self.map[t][0] or 'default'
         if ttype not in self.ecache:
             try: