From c8ea36e881bbd56cfd2aadb8fd1f4da0dfcd19ed Mon Sep 17 00:00:00 2001
From: Jeff Roberson <jeff@FreeBSD.org>
Date: Tue, 4 Feb 2020 02:42:54 +0000
Subject: [PATCH] Fix a recursion on the thread lock by acquiring it after call
 rtp_to_pri().

Reported by:	swills
Reviewed by:	kib, markj
Differential Revision:	https://reviews.freebsd.org/D23495
---
 sys/kern/kern_thr.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/sys/kern/kern_thr.c b/sys/kern/kern_thr.c
index da47cf9a517..2f361fbdd25 100644
--- a/sys/kern/kern_thr.c
+++ b/sys/kern/kern_thr.c
@@ -271,14 +271,12 @@ thread_create(struct thread *td, struct rtprio *rtp,
 
 	tidhash_add(newtd);
 
+	/* ignore timesharing class */
+	if (rtp != NULL && !(td->td_pri_class == PRI_TIMESHARE &&
+	    rtp->type == RTP_PRIO_NORMAL))
+		rtp_to_pri(rtp, newtd);
+
 	thread_lock(newtd);
-	if (rtp != NULL) {
-		if (!(td->td_pri_class == PRI_TIMESHARE &&
-		      rtp->type == RTP_PRIO_NORMAL)) {
-			rtp_to_pri(rtp, newtd);
-			sched_prio(newtd, newtd->td_user_pri);
-		} /* ignore timesharing class */
-	}
 	TD_SET_CAN_RUN(newtd);
 	sched_add(newtd, SRQ_BORING);