diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index bbb0d6e5c81..6e81a9d6fe5 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -2367,7 +2367,7 @@ def _compare_cpu(self, cpu_info):
             raise
 
         if ret <= 0:
-            LOG.error(reason=m % locals())
+            LOG.error(m % locals())
             raise exception.InvalidCPUInfo(reason=m % locals())
 
     def _create_shared_storage_test_file(self):