From: Inbar Karmy <inbark@mellanox.com>
Date: Tue, 10 Oct 2017 12:28:34 +0300
Subject: net/mlx4_en: Limit the number of RX rings
Patch-mainline: v4.15-rc1
Git-commit: b8d394367a631c2d749b3114e04dfb4d09624ddf
References: bsc#1103989 FATE#326004

Limit the number of RX rings by the number of cores
in the system.

Signed-off-by: Inbar Karmy <inbark@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
@@ -1742,12 +1742,17 @@ static int mlx4_en_set_rxnfc(struct net_
 	return err;
 }
 
+static int mlx4_en_get_max_num_rx_rings(struct net_device *dev)
+{
+	return min_t(int, num_online_cpus(), MAX_RX_RINGS);
+}
+
 static void mlx4_en_get_channels(struct net_device *dev,
 				 struct ethtool_channels *channel)
 {
 	struct mlx4_en_priv *priv = netdev_priv(dev);
 
-	channel->max_rx = MAX_RX_RINGS;
+	channel->max_rx = mlx4_en_get_max_num_rx_rings(dev);
 	channel->max_tx = priv->mdev->profile.max_num_tx_rings_p_up;
 
 	channel->rx_count = priv->rx_ring_num;