trace: stop tracer in oops_enter()

If trace_printk_on_oops is set we lose interesting trace information
when the tracer is enabled across oops handling and printing. We want
the trace which might give us information _WHY_ we oopsed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/panic.c b/kernel/panic.c
index 984b3ec..512ab73 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -301,6 +301,7 @@
  */
 void oops_enter(void)
 {
+	tracing_off();
 	/* can't trust the integrity of the kernel anymore: */
 	debug_locks_off();
 	do_oops_enter_exit();