From: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx> This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== commit 5f8bf2d263a20b986225ae1ed7d6759dc4b93af9 upstream. Running my ftrace tests on PowerPC, it failed the test that checks if function_graph tracer is affected by the stack tracer. It was. Looking into this, I found that the update_function_graph_func() must be called even if the trampoline function is not changed. This is because archs like PowerPC do not support ftrace_ops being passed by assembly and instead uses a helper function (what the trampoline function points to). Since this function is not changed even when multiple ftrace_ops are added to the code, the test that falls out before calling update_function_graph_func() will miss that the update must still be done. Call update_function_graph_function() for all calls to update_ftrace_function() Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- kernel/trace/ftrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index a8642bac843e..d2ab10b3a30e 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -331,12 +331,12 @@ static void update_ftrace_function(void) func = ftrace_ops_list_func; } + update_function_graph_func(); + /* If there's no change, then do nothing more here */ if (ftrace_trace_function == func) return; - update_function_graph_func(); - /* * If we are using the list function, it doesn't care * about the function_trace_ops. -- 2.0.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html