From: Usha Ketineni <usha.k.ketineni@intel.com>
Date: Wed, 6 Nov 2019 02:05:31 -0800
Subject: ice: Fix to change Rx/Tx ring descriptor size via ethtool with DCBx
Patch-mainline: v5.5-rc1
Git-commit: c0a3665f71a2f086800abea4d9d14d28269089d6
References: jsc#SLE-7926

This patch fixes the call trace caused by the kernel when the Rx/Tx
descriptor size change request is initiated via ethtool when DCB is
configured. ice_set_ringparam() should use vsi->num_txq instead of
vsi->alloc_txq as it represents the queues that are enabled in the
driver when DCB is enabled/disabled. Otherwise, queue index being
used can go out of range.

For example, when vsi->alloc_txq has 104 queues and with 3 TCS enabled
via DCB, each TC gets 34 queues, vsi->num_txq will be 102 and only 102
queues will be enabled.

Signed-off-by: Usha Ketineni <usha.k.ketineni@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/ice/ice_ethtool.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -2654,14 +2654,14 @@ ice_set_ringparam(struct net_device *net
 	netdev_info(netdev, "Changing Tx descriptor count from %d to %d\n",
 		    vsi->tx_rings[0]->count, new_tx_cnt);
 
-	tx_rings = devm_kcalloc(&pf->pdev->dev, vsi->alloc_txq,
+	tx_rings = devm_kcalloc(&pf->pdev->dev, vsi->num_txq,
 				sizeof(*tx_rings), GFP_KERNEL);
 	if (!tx_rings) {
 		err = -ENOMEM;
 		goto done;
 	}
 
-	for (i = 0; i < vsi->alloc_txq; i++) {
+	ice_for_each_txq(vsi, i) {
 		/* clone ring and setup updated count */
 		tx_rings[i] = *vsi->tx_rings[i];
 		tx_rings[i].count = new_tx_cnt;
@@ -2714,14 +2714,14 @@ process_rx:
 	netdev_info(netdev, "Changing Rx descriptor count from %d to %d\n",
 		    vsi->rx_rings[0]->count, new_rx_cnt);
 
-	rx_rings = devm_kcalloc(&pf->pdev->dev, vsi->alloc_rxq,
+	rx_rings = devm_kcalloc(&pf->pdev->dev, vsi->num_rxq,
 				sizeof(*rx_rings), GFP_KERNEL);
 	if (!rx_rings) {
 		err = -ENOMEM;
 		goto done;
 	}
 
-	for (i = 0; i < vsi->alloc_rxq; i++) {
+	ice_for_each_rxq(vsi, i) {
 		/* clone ring and setup updated count */
 		rx_rings[i] = *vsi->rx_rings[i];
 		rx_rings[i].count = new_rx_cnt;
@@ -2759,7 +2759,7 @@ process_link:
 		ice_down(vsi);
 
 		if (tx_rings) {
-			for (i = 0; i < vsi->alloc_txq; i++) {
+			ice_for_each_txq(vsi, i) {
 				ice_free_tx_ring(vsi->tx_rings[i]);
 				*vsi->tx_rings[i] = tx_rings[i];
 			}
@@ -2767,7 +2767,7 @@ process_link:
 		}
 
 		if (rx_rings) {
-			for (i = 0; i < vsi->alloc_rxq; i++) {
+			ice_for_each_rxq(vsi, i) {
 				ice_free_rx_ring(vsi->rx_rings[i]);
 				/* copy the real tail offset */
 				rx_rings[i].tail = vsi->rx_rings[i]->tail;
@@ -2801,7 +2801,7 @@ process_link:
 free_tx:
 	/* error cleanup if the Rx allocations failed after getting Tx */
 	if (tx_rings) {
-		for (i = 0; i < vsi->alloc_txq; i++)
+		ice_for_each_txq(vsi, i)
 			ice_free_tx_ring(&tx_rings[i]);
 		devm_kfree(&pf->pdev->dev, tx_rings);
 	}