diff --git a/mercurial/ui.py b/mercurial/ui.py
index a8feb88ddc..cdbd6ba7e0 100644
--- a/mercurial/ui.py
+++ b/mercurial/ui.py
@@ -1201,16 +1201,18 @@ class ui(object):
         `overrides` must be a dict of the following structure:
         {(section, name) : value}"""
         backups = {}
-        for (section, name), value in overrides.items():
-            backups[(section, name)] = self.backupconfig(section, name)
-            self.setconfig(section, name, value, source)
-        yield
-        for __, backup in backups.items():
-            self.restoreconfig(backup)
-        # just restoring ui.quiet config to the previous value is not enough
-        # as it does not update ui.quiet class member
-        if ('ui', 'quiet') in overrides:
-            self.fixconfig(section='ui')
+        try:
+            for (section, name), value in overrides.items():
+                backups[(section, name)] = self.backupconfig(section, name)
+                self.setconfig(section, name, value, source)
+            yield
+        finally:
+            for __, backup in backups.items():
+                self.restoreconfig(backup)
+            # just restoring ui.quiet config to the previous value is not enough
+            # as it does not update ui.quiet class member
+            if ('ui', 'quiet') in overrides:
+                self.fixconfig(section='ui')
 
 class paths(dict):
     """Represents a collection of paths and their configs.