nvme-tcp: block BH in sk state_change sk callback

BugLink: https://bugs.launchpad.net/bugs/1929615

[ Upstream commit 8b73b45 ]

The TCP stack can run from process context for a long time
so we should disable BH here.

Fixes: 3f2304f ("nvme-tcp: add NVMe over TCP host driver")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

Author: sagigrimberg

drivers/nvme/host/tcp.c

@@ -816,7 +816,7 @@ static void nvme_tcp_state_change(struct sock *sk)
 {
 	struct nvme_tcp_queue *queue;
 
-	read_lock(&sk->sk_callback_lock);
+	read_lock_bh(&sk->sk_callback_lock);
 	queue = sk->sk_user_data;
 	if (!queue)
 		goto done;
@@ -838,7 +838,7 @@ static void nvme_tcp_state_change(struct sock *sk)
 
 	queue->state_change(sk);
 done:
-	read_unlock(&sk->sk_callback_lock);
+	read_unlock_bh(&sk->sk_callback_lock);
 }
 
 static inline void nvme_tcp_done_send_req(struct nvme_tcp_queue *queue)