Re: [syzbot] [net?] INFO: rcu detected stall in sys_socket

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Subject: [net?] INFO: rcu detected stall in sys_socket
Author: eadavis@qq.com

please test rcu detected stall in sys_socket

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 18d46e76d7c2

diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 31a8252bd09c..4bc377120ea0 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -843,6 +843,7 @@ static struct sk_buff *taprio_dequeue(struct Qdisc *sch)
 
 	rcu_read_lock();
 	entry = rcu_dereference(q->current_entry);
+	rcu_read_unlock();
 	/* if there's no entry, it means that the schedule didn't
 	 * start yet, so force all gates to be open, this is in
 	 * accordance to IEEE 802.1Qbv-2015 Section 8.6.9.4.5
@@ -869,8 +870,6 @@ static struct sk_buff *taprio_dequeue(struct Qdisc *sch)
 	}
 
 done:
-	rcu_read_unlock();
-
 	return skb;
 }