diff --git a/sched/misc/assert.c b/sched/misc/assert.c
index 8c29e471ebf..ac17b3460b6 100644
--- a/sched/misc/assert.c
+++ b/sched/misc/assert.c
@@ -559,6 +559,8 @@ void _assert(FAR const char *filename, int linenum,
 
   flags = enter_critical_section();
 
+  sched_lock();
+
   /* try to save current context if regs is null */
 
   if (regs == NULL)
@@ -680,5 +682,7 @@ void _assert(FAR const char *filename, int linenum,
 #endif
     }
 
+  sched_unlock();
+
   leave_critical_section(flags);
 }