ftrace: add stack tracing

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 3f73a17..eb1988e 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -10,6 +10,7 @@
 config TRACING
 	bool
 	select DEBUG_FS
+	select STACKTRACE
 
 config FTRACE
 	bool "Kernel Function Tracer"