ibmvnic: Allocate statistics buffers during probe

Currently, buffers holding individual queue statistics are allocated
when the device is opened. If an ibmvnic interface is hotplugged or
initialized but never opened, an attempt to get statistics with
ethtool will result in a kernel panic.

Since the driver allocates a constant number, the maximum supported
queues, of buffers, these can be allocated during device probe and
freed when the device is hot-unplugged or the module is removed.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/ibmvnic.c

@@ -845,8 +845,6 @@ static void release_resources(struct ibmvnic_adapter *adapter)
 	release_tx_pools(adapter);
 	release_rx_pools(adapter);
 
-	release_stats_token(adapter);
-	release_stats_buffers(adapter);
 	release_error_buffers(adapter);
 	release_napi(adapter);
 	release_login_rsp_buffer(adapter);
@@ -974,14 +972,6 @@ static int init_resources(struct ibmvnic_adapter *adapter)
 	if (rc)
 		return rc;
 
-	rc = init_stats_buffers(adapter);
-	if (rc)
-		return rc;
-
-	rc = init_stats_token(adapter);
-	if (rc)
-		return rc;
-
 	adapter->vpd = kzalloc(sizeof(*adapter->vpd), GFP_KERNEL);
 	if (!adapter->vpd)
 		return -ENOMEM;
@@ -4431,6 +4421,14 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
 		release_crq_queue(adapter);
 	}
 
+	rc = init_stats_buffers(adapter);
+	if (rc)
+		return rc;
+
+	rc = init_stats_token(adapter);
+	if (rc)
+		return rc;
+
 	return rc;
 }
 
@@ -4538,6 +4536,9 @@ static int ibmvnic_remove(struct vio_dev *dev)
 	release_sub_crqs(adapter, 1);
 	release_crq_queue(adapter);
 
+	release_stats_token(adapter);
+	release_stats_buffers(adapter);
+
 	adapter->state = VNIC_REMOVED;
 
 	mutex_unlock(&adapter->reset_lock);