diff --git a/xen/common/debugtrace.c b/xen/common/debugtrace.c
index a788e55b4c..11ac198d93 100644
--- a/xen/common/debugtrace.c
+++ b/xen/common/debugtrace.c
@@ -94,7 +94,7 @@ static void debugtrace_dump_worker(void)
 
     debugtrace_dump_buffer(dt_data, "global");
 
-    for ( cpu = 0; cpu < nr_cpu_ids; cpu++ )
+    for_each_online_cpu ( cpu )
     {
         char buf[16];