From dd75b5addb9ca34ee16657197b96cf118800d97f Mon Sep 17 00:00:00 2001
From: Robert Hancock <robert.hancock@calian.com>
Date: Tue, 18 Jan 2022 15:41:28 -0600
Subject: [PATCH 13/34] net: axienet: limit minimum TX ring size
Git-commit: 70f5817deddbc6ef3faa35841cab83c280cc653a
References: git-fixes
Patch-mainline: v5.17-rc1
The driver will not work properly if the TX ring size is set to below
MAX_SKB_FRAGS + 1 since it needs to hold at least one full maximally
fragmented packet in the TX ring. Limit setting the ring size to below
this value.
Fixes: 8b09ca823ffb4 ("net: axienet: Make RX/TX ring sizes configurable")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 33621015cebd..95ac3c797570 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -43,6 +43,7 @@
/* Descriptors defines for Tx and Rx DMA */
#define TX_BD_NUM_DEFAULT 64
#define RX_BD_NUM_DEFAULT 1024
+#define TX_BD_NUM_MIN (MAX_SKB_FRAGS + 1)
#define TX_BD_NUM_MAX 4096
#define RX_BD_NUM_MAX 4096
@@ -1364,7 +1365,8 @@ static int axienet_ethtools_set_ringparam(struct net_device *ndev,
if (ering->rx_pending > RX_BD_NUM_MAX ||
ering->rx_mini_pending ||
ering->rx_jumbo_pending ||
- ering->rx_pending > TX_BD_NUM_MAX)
+ ering->tx_pending < TX_BD_NUM_MIN ||
+ ering->tx_pending > TX_BD_NUM_MAX)
return -EINVAL;
if (netif_running(ndev))
--
2.16.4