diff --git a/tools/misc/xenpm.c b/tools/misc/xenpm.c
index 86c12ea5fb..65aa4c9d42 100644
--- a/tools/misc/xenpm.c
+++ b/tools/misc/xenpm.c
@@ -1231,7 +1231,7 @@ int main(int argc, char *argv[])
         xc_interface_close(xc_handle);
         return ret;
     }
-    max_cpu_nr = physinfo.nr_cpus;
+    max_cpu_nr = physinfo.max_cpu_id + 1;
 
     /* calculate how many options match with user's input */
     for ( i = 0; i < ARRAY_SIZE(main_options); i++ )