[PATCH net-next] ibmvnic: Track state of adapter napis

[PATCH net-next] ibmvnic: Track state of adapter napis

[John Allen]

Track the state of ibmvnic napis. The driver can get into states where it
can be reset when napis are already disabled and attempting to disable them
again will cause the driver to hang.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
---
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 4f2d329..594ee6d 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -675,8 +675,12 @@ static int __ibmvnic_open(struct net_device *netdev)
 	adapter->state = VNIC_OPENING;
 	replenish_pools(adapter);

-	for (i = 0; i < adapter->req_rx_queues; i++)
-		napi_enable(&adapter->napi[i]);
+	if (adapter->napi_disabled) {
+		for (i = 0; i < adapter->req_rx_queues; i++)
+			napi_enable(&adapter->napi[i]);
+
+		adapter->napi_disabled = false;
+	}

 	/* We're ready to receive frames, enable the sub-crq interrupts and
 	 * set the logical link state to up
@@ -780,9 +784,11 @@ static int __ibmvnic_close(struct net_device *netdev)
 	adapter->state = VNIC_CLOSING;
 	netif_tx_stop_all_queues(netdev);

-	if (adapter->napi) {
+	if (!adapter->napi_disabled) {
 		for (i = 0; i < adapter->req_rx_queues; i++)
 			napi_disable(&adapter->napi[i]);
+
+		adapter->napi_disabled = true;
 	}

 	clean_tx_pools(adapter);
@@ -3540,6 +3546,9 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
 		free_netdev(netdev);
 		return rc;
 	}
+
+	adapter->napi_disabled = true;
+
 	dev_info(&dev->dev, "ibmvnic registered\n");

 	adapter->state = VNIC_PROBED;
diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h
index 4702b48..12b2400 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.h
+++ b/drivers/net/ethernet/ibm/ibmvnic.h
@@ -1031,4 +1031,5 @@ struct ibmvnic_adapter {
 	struct list_head rwi_list;
 	struct work_struct ibmvnic_reset;
 	bool resetting;
+	bool napi_disabled;
 };

Re: [PATCH net-next] ibmvnic: Track state of adapter napis

[David Miller]

From: John Allen <jallen@linux.vnet.ibm.com>
Date: Fri, 5 May 2017 11:31:58 -0500

> Track the state of ibmvnic napis. The driver can get into states where it
> can be reset when napis are already disabled and attempting to disable them
> again will cause the driver to hang.
> 
> Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>

The net-next tree is closed, resubmit this when the net-next tree opens
back up.

Thanks.