[PATCH 02/14] tracing: Return -EINVAL if a boot tracer tries to enable the mmiotracer at boot

[Steven Rostedt]

From: Steven Rostedt <rostedt@xxxxxxxxxxx>

The mmiotracer is not set to be enabled at boot up from the kernel command
line. If the boot command line tries to enable that tracer, it will fail
to be enabled. The return code is currently zero when that happens so the
caller just thinks it was enabled. Return -EINVAL in this case.

Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 77e9bf271c04..3878e80f55d9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6107,7 +6107,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
 	if (system_state < SYSTEM_RUNNING && t->noboot) {
 		pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
 			t->name);
-		return 0;
+		return -EINVAL;
 	}
 
 	/* Some tracers are only allowed for the top level buffer */
-- 
2.45.2