From: Karsten Graul <kgraul@linux.ibm.com>
Date: Wed, 30 Jan 2019 18:51:06 +0100
Subject: net/smc: call smc_cdc_msg_send() under send_lock
Git-commit: 2dee25af42f99b476d5916aeac5c994e4dcc910b
Patch-mainline: v5.0-rc6
References: bsc#1129857 bsc#1129861 LTC#176247 LTC#176250

Call smc_cdc_msg_send() under the connection send_lock to make sure all
send operations for one connection are serialized.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 net/smc/smc_cdc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
index db83332ac1c8..1c5333d494e9 100644
--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -125,7 +125,10 @@ static int smcr_cdc_get_slot_and_msg_send(struct smc_connection *conn)
 	if (rc)
 		return rc;
 
-	return smc_cdc_msg_send(conn, wr_buf, pend);
+	spin_lock_bh(&conn->send_lock);
+	rc = smc_cdc_msg_send(conn, wr_buf, pend);
+	spin_unlock_bh(&conn->send_lock);
+	return rc;
 }
 
 int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)