diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index b2e8e49..43e521e 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -108,10 +108,10 @@
 		return 0;
 
 	/* FIXME: should we process all CPU buffers ? */
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
 	add_event_entry(ESCAPE_CODE);
 	add_event_entry(MODULE_LOADED_CODE);
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 #endif
 	return 0;
 }
@@ -501,7 +501,7 @@
 	sync_buffer_state state = sb_buffer_start;
 	unsigned long available;
 
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
  
 	add_cpu_switch(cpu);
 
@@ -550,5 +550,5 @@
 
 	mark_done(cpu);
 
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 }