ftrace: Remove unnecessary disabling of irqs
The disabling of interrupts around ftrace_update_code() was used
to protect against the evil ftrace daemon from years past. But that
daemon has long been killed. It is safe to keep interrupts enabled
while updating the initial mcount into nops.
The ftrace_mutex is also held which keeps other users at bay.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4ff65599..f199fb2 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2707,7 +2707,6 @@
{
unsigned long *p;
unsigned long addr;
- unsigned long flags;
mutex_lock(&ftrace_lock);
p = start;
@@ -2724,10 +2723,7 @@
ftrace_record_ip(addr);
}
- /* disable interrupts to prevent kstop machine */
- local_irq_save(flags);
ftrace_update_code(mod);
- local_irq_restore(flags);
mutex_unlock(&ftrace_lock);
return 0;