diff --git a/tools/patman/func_test.py b/tools/patman/func_test.py
index b39e3f6..cce3905 100644
--- a/tools/patman/func_test.py
+++ b/tools/patman/func_test.py
@@ -588,3 +588,22 @@
         self.assertEqual(
             ["Found possible blank line(s) at end of file 'lib/fdtdec.c'"],
             pstrm.commit.warn)
+
+    @unittest.skipIf(not HAVE_PYGIT2, 'Missing python3-pygit2')
+    def testNoUpstream(self):
+        """Test CountCommitsToBranch when there is no upstream"""
+        repo = self.make_git_tree()
+        target = repo.lookup_reference('refs/heads/base')
+        self.repo.checkout(target, strategy=pygit2.GIT_CHECKOUT_FORCE)
+
+        # Check that it can detect the current branch
+        try:
+            orig_dir = os.getcwd()
+            os.chdir(self.gitdir)
+            with self.assertRaises(ValueError) as exc:
+                gitutil.CountCommitsToBranch(None)
+            self.assertIn(
+                "Failed to determine upstream: fatal: no upstream configured for branch 'base'",
+                str(exc.exception))
+        finally:
+            os.chdir(orig_dir)
diff --git a/tools/patman/gitutil.py b/tools/patman/gitutil.py
index 27a0a9f..3a2366bc 100644
--- a/tools/patman/gitutil.py
+++ b/tools/patman/gitutil.py
@@ -66,9 +66,13 @@
         rev_range = '%s..%s' % (us, branch)
     else:
         rev_range = '@{upstream}..'
-    pipe = [LogCmd(rev_range, oneline=True), ['wc', '-l']]
-    stdout = command.RunPipe(pipe, capture=True, oneline=True).stdout
-    patch_count = int(stdout)
+    pipe = [LogCmd(rev_range, oneline=True)]
+    result = command.RunPipe(pipe, capture=True, capture_stderr=True,
+                             oneline=True, raise_on_error=False)
+    if result.return_code:
+        raise ValueError('Failed to determine upstream: %s' %
+                         result.stderr.strip())
+    patch_count = len(result.stdout.splitlines())
     return patch_count
 
 def NameRevision(commit_hash):