[PATCH 4.19 25/86] bnxt_en: Fix race when modifying pause settings.

[Greg Kroah-Hartman]

From: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>

[ Upstream commit 163e9ef63641a02de4c95cd921577265c52e1ce2 ]

The driver was modified to not rely on rtnl lock to protect link
settings about 2 years ago.  The pause setting was missed when
making that change.  Fix it by acquiring link_lock mutex before
calling bnxt_hwrm_set_pause().

Fixes: e2dc9b6e38fa ("bnxt_en: Don't use rtnl lock to protect link change logic in workqueue.")
Signed-off-by: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>
Reviewed-by: Edwin Peer <edwin.peer@xxxxxxxxxxxx>
Signed-off-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 047024717d654..63730e449e088 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1392,8 +1392,11 @@ static int bnxt_set_pauseparam(struct net_device *dev,
 	if (epause->tx_pause)
 		link_info->req_flow_ctrl |= BNXT_LINK_PAUSE_TX;
 
-	if (netif_running(dev))
+	if (netif_running(dev)) {
+		mutex_lock(&bp->link_lock);
 		rc = bnxt_hwrm_set_pause(bp);
+		mutex_unlock(&bp->link_lock);
+	}
 	return rc;
 }
 
-- 
2.25.1