[PATCH AUTOSEL 4.19 63/64] qede: Fix system crash on configuring channels.

Sasha Levin
2019-02-28T15:22:48Z

From: Sudarsana Reddy Kalluru <skalluru@marvell.com>

[ Upstream commit 0aa4febb420d91df5b56b1864a2465765da85f4b ]

Under heavy traffic load, when changing number of channels via
ethtool (ethtool -L) which will cause interface to be reloaded,
it was observed that some packets gets transmitted on old TX
channel/queue id which doesn't really exist after the channel
configuration leads to system crash.

Add a safeguard in the driver by validating queue id through
ndo_select_queue() which is called before the ndo_start_xmit().

Signed-off-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/qlogic/qede/qede.h | 3 +++
drivers/net/ethernet/qlogic/qede/qede_fp.c | 13 +++++++++++++
drivers/net/ethernet/qlogic/qede/qede_main.c | 3 +++
3 files changed, 19 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qede/qede.h b/drivers/net/ethernet/qlogic/qede/qede.h
index 6a4d266fb8e21..d242a57240691 100644
--- a/drivers/net/ethernet/qlogic/qede/qede.h
+++ b/drivers/net/ethernet/qlogic/qede/qede.h
@@ -489,6 +489,9 @@ struct qede_reload_args {

/* Datapath functions definition */
netdev_tx_t qede_start_xmit(struct sk_buff *skb, struct net_device *ndev);
+u16 qede_select_queue(struct net_device *dev, struct sk_buff *skb,
+ struct net_device *sb_dev,
+ select_queue_fallback_t fallback);
netdev_features_t qede_features_check(struct sk_buff *skb,
struct net_device *dev,
netdev_features_t features);
diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c b/drivers/net/ethernet/qlogic/qede/qede_fp.c
index 1a78027de071f..a96da16f34049 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_fp.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c
@@ -1695,6 +1695,19 @@ netdev_tx_t qede_start_xmit(struct sk_buff *skb, struct net_device *ndev)
return NETDEV_TX_OK;
}

+u16 qede_select_queue(struct net_device *dev, struct sk_buff *skb,
+ struct net_device *sb_dev,
+ select_queue_fallback_t fallback)
+{
+ struct qede_dev *edev = netdev_priv(dev);
+ int total_txq;
+
+ total_txq = QEDE_TSS_COUNT(edev) * edev->dev_info.num_tc;
+
+ return QEDE_TSS_COUNT(edev) ?
+ fallback(dev, skb, NULL) % total_txq : 0;
+}
+
/* 8B udp header + 8B base tunnel header + 32B option length */
#define QEDE_MAX_TUN_HDR_LEN 48

diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c b/drivers/net/ethernet/qlogic/qede/qede_main.c
index 46d0f2eaa0c09..f3d9c40c41159 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_main.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
@@ -631,6 +631,7 @@ static const struct net_device_ops qede_netdev_ops = {
.ndo_open = qede_open,
.ndo_stop = qede_close,
.ndo_start_xmit = qede_start_xmit,
+ .ndo_select_queue = qede_select_queue,
.ndo_set_rx_mode = qede_set_rx_mode,
.ndo_set_mac_address = qede_set_mac_addr,
.ndo_validate_addr = eth_validate_addr,
@@ -666,6 +667,7 @@ static const struct net_device_ops qede_netdev_vf_ops = {
.ndo_open = qede_open,
.ndo_stop = qede_close,
.ndo_start_xmit = qede_start_xmit,
+ .ndo_select_queue = qede_select_queue,
.ndo_set_rx_mode = qede_set_rx_mode,
.ndo_set_mac_address = qede_set_mac_addr,
.ndo_validate_addr = eth_validate_addr,
@@ -684,6 +686,7 @@ static const struct net_device_ops qede_netdev_vf_xdp_ops = {
.ndo_open = qede_open,
.ndo_stop = qede_close,
.ndo_start_xmit = qede_start_xmit,
+ .ndo_select_queue = qede_select_queue,
.ndo_set_rx_mode = qede_set_rx_mode,
.ndo_set_mac_address = qede_set_mac_addr,
.ndo_validate_addr = eth_validate_addr,
--
2.19.1