i40e: don't free nonexistent rings

Not all VSIs have rings! Check to see if rings were actually allocated before
freeing them.

This prevents a panic when tx_rings[0] is not allocated.

Signed-off-by: Mitch Williams <[email protected]>
Signed-off-by: Jesse Brandeburg <[email protected]>
Tested-by: Sibai Li <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 69ed8014afbd78c699fc513cfeea9453449e7520..a8c18faf1c5448275ba31f278ef78e96b30e5acf 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -5160,11 +5160,12 @@ static s32 i40e_vsi_clear_rings(struct i40e_vsi *vsi)
 {
        int i;
 
-       for (i = 0; i < vsi->alloc_queue_pairs; i++) {
-               kfree_rcu(vsi->tx_rings[i], rcu);
-               vsi->tx_rings[i] = NULL;
-               vsi->rx_rings[i] = NULL;
-       }
+       if (vsi->tx_rings[0])
+               for (i = 0; i < vsi->alloc_queue_pairs; i++) {
+                       kfree_rcu(vsi->tx_rings[i], rcu);
+                       vsi->tx_rings[i] = NULL;
+                       vsi->rx_rings[i] = NULL;
+               }
 
        return 0;
 }