[PATCH 5.4 07/34] iavf: Fix limit of total number of queues to active queues of VF

[Greg Kroah-Hartman]

From: Karen Sornek <karen.sornek@xxxxxxxxx>

commit b712941c8085e638bb92456e866ed3de4404e3d5 upstream.

In the absence of this validation, if the user requests to
configure queues more than the enabled queues, it results in
sending the requested number of queues to the kernel stack
(due to the asynchronous nature of VF response), in which
case the stack might pick a queue to transmit that is not
enabled and result in Tx hang. Fix this bug by
limiting the total number of queues allocated for VF to
active queues of VF.

Fixes: d5b33d024496 ("i40evf: add ndo_setup_tc callback to i40evf")
Signed-off-by: Ashwin Vijayavel <ashwin.vijayavel@xxxxxxxxx>
Signed-off-by: Karen Sornek <karen.sornek@xxxxxxxxx>
Tested-by: Konrad Jankowski <konrad0.jankowski@xxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/intel/iavf/iavf_main.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2604,8 +2604,11 @@ static int iavf_validate_ch_config(struc
 		total_max_rate += tx_rate;
 		num_qps += mqprio_qopt->qopt.count[i];
 	}
-	if (num_qps > IAVF_MAX_REQ_QUEUES)
+	if (num_qps > adapter->num_active_queues) {
+		dev_err(&adapter->pdev->dev,
+			"Cannot support requested number of queues\n");
 		return -EINVAL;
+	}
 
 	ret = iavf_validate_tx_bandwidth(adapter, total_max_rate);
 	return ret;