Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8ab2b7ef authored by Steven Rostedt's avatar Steven Rostedt Committed by Steven Rostedt
Browse files

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: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 0778d9ad

kernel/trace/ftrace.c

+0 −4
Original line number Original line Diff line number Diff line
@@ -2707,7 +2707,6 @@ static int ftrace_process_locs(struct module *mod, 
{

{

	unsigned long *p;

	unsigned long *p;

	unsigned long addr;

	unsigned long addr;

	unsigned long flags;





	mutex_lock(&ftrace_lock);

	mutex_lock(&ftrace_lock);

	p = start;

	p = start;
@@ -2724,10 +2723,7 @@ static int ftrace_process_locs(struct module *mod, 
		ftrace_record_ip(addr);

		ftrace_record_ip(addr);

	}

	}





	/* disable interrupts to prevent kstop machine */

	local_irq_save(flags);

	ftrace_update_code(mod);

	ftrace_update_code(mod);

	local_irq_restore(flags);

	mutex_unlock(&ftrace_lock);

	mutex_unlock(&ftrace_lock);





	return 0;

	return 0;