octeontx2-pf: Fix interface down flag on error

[ Upstream commit 69f0aeb ]

In the existing code while changing the number of TX/RX
queues using ethtool the PF/VF interface resources are
freed and reallocated (otx2_stop and otx2_open is called)
if the device is in running state. If any resource allocation
fails in otx2_open, driver free already allocated resources
and return. But again, when the number of queues changes
as the device state still running oxt2_stop is called.
In which we try to free already freed resources leading
to driver crash.
This patch fixes the issue by setting the INTF_DOWN flag on
error and free the resources in otx2_stop only if the flag is
not set.

Fixes: 50fe6c0 ("octeontx2-pf: Register and handle link notifications")
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <Sunil.Goutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c

@@ -292,15 +292,14 @@ static int otx2_set_channels(struct net_device *dev,
 	err = otx2_set_real_num_queues(dev, channel->tx_count,
 				       channel->rx_count);
 	if (err)
-		goto fail;
+		return err;
 
 	pfvf->hw.rx_queues = channel->rx_count;
 	pfvf->hw.tx_queues = channel->tx_count;
 	pfvf->qset.cq_cnt = pfvf->hw.tx_queues +  pfvf->hw.rx_queues;
 
-fail:
 	if (if_up)
-		dev->netdev_ops->ndo_open(dev);
+		err = dev->netdev_ops->ndo_open(dev);
 
 	netdev_info(dev, "Setting num Tx rings to %d, Rx rings to %d success\n",
 		    pfvf->hw.tx_queues, pfvf->hw.rx_queues);
@@ -404,7 +403,7 @@ static int otx2_set_ringparam(struct net_device *netdev,
 	qs->rqe_cnt = rx_count;
 
 	if (if_up)
-		netdev->netdev_ops->ndo_open(netdev);
+		return netdev->netdev_ops->ndo_open(netdev);
 
 	return 0;
 }

drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c

@@ -1648,6 +1648,7 @@ int otx2_open(struct net_device *netdev)
 err_tx_stop_queues:
 	netif_tx_stop_all_queues(netdev);
 	netif_carrier_off(netdev);
+	pf->flags |= OTX2_FLAG_INTF_DOWN;
 err_free_cints:
 	otx2_free_cints(pf, qidx);
 	vec = pci_irq_vector(pf->pdev,
@@ -1675,6 +1676,10 @@ int otx2_stop(struct net_device *netdev)
 	struct otx2_rss_info *rss;
 	int qidx, vec, wrk;
 
+	/* If the DOWN flag is set resources are already freed */
+	if (pf->flags & OTX2_FLAG_INTF_DOWN)
+		return 0;
+
 	netif_carrier_off(netdev);
 	netif_tx_stop_all_queues(netdev);