1 files changed, 10 insertions, 9 deletions

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index b1342c5d37c..f2252296607 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -212,9 +212,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
         int cpu;
         int pc;
 
-        if (unlikely(!tr))
-                return 0;
-
         if (!ftrace_trace_task(current))
                 return 0;
 
@@ -287,11 +284,20 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
         local_irq_restore(flags);
 }
 
+void set_graph_array(struct trace_array *tr)
+{
+        graph_array = tr;
+
+        /* Make graph_array visible before we start tracing */
+
+        smp_mb();
+}
+
 static int graph_trace_init(struct trace_array *tr)
 {
         int ret;
 
-        graph_array = tr;
+        set_graph_array(tr);
         ret = register_ftrace_graph(&trace_graph_return,
                                     &trace_graph_entry);
         if (ret)
@@ -301,11 +307,6 @@ static int graph_trace_init(struct trace_array *tr)
         return 0;
 }
 
-void set_graph_array(struct trace_array *tr)
-{
-        graph_array = tr;
-}
-
 static void graph_trace_reset(struct trace_array *tr)
 {
         tracing_stop_cmdline_record();