diff --git a/sys/kern/kern_sched.c b/sys/kern/kern_sched.c
--- a/sys/kern/kern_sched.c
+++ b/sys/kern/kern_sched.c
@@ -145,6 +145,8 @@
 {
 	if (RTP_PRIO_IS_REALTIME(lp->lwp_rtprio.type))
 		param->sched_priority = rtpprio_to_p4prio(lp->lwp_rtprio.prio);
+	else
+		param->sched_priority = P1B_PRIO_MIN;
 
 	return 0;
 }