@@ -643,9 +643,13 @@ int fm10k_close(struct net_device *netdev)
static netdev_tx_t fm10k_xmit_frame(struct sk_buff *skb, struct net_device *dev)
{
struct fm10k_intfc *interface = netdev_priv(dev);
+ int num_tx_queues = READ_ONCE(interface->num_tx_queues);
unsigned int r_idx = skb->queue_mapping;
int err;
+ if (!num_tx_queues)
+ return NETDEV_TX_BUSY;
+
if ((skb->protocol == htons(ETH_P_8021Q)) &&
!skb_vlan_tag_present(skb)) {
/* FM10K only supports hardware tagging, any tags in frame
@@ -698,8 +702,8 @@ static netdev_tx_t fm10k_xmit_frame(struct sk_buff *skb, struct net_device *dev)
__skb_put(skb, pad_len);
}
- if (r_idx >= interface->num_tx_queues)
- r_idx %= interface->num_tx_queues;
+ if (r_idx >= num_tx_queues)
+ r_idx %= num_tx_queues;
err = fm10k_xmit_frame_ring(skb, interface->tx_ring[r_idx]);
It is possible that under rare circumstances the device is undergoing a reset, such as when a PFLR occurs, and the device may be transmitting simultaneously. In this case, we might attempt to divide by zero when finding the proper r_idx. Instead, lets read the num_tx_queues once, and make sure it's non-zero. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> --- drivers/net/ethernet/intel/fm10k/fm10k_netdev.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)