Merge tag 'for-linus-4.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Only five small fixes for issues when running under Xen"

* tag 'for-linus-4.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Fix {set,clear}_foreign_p2m_mapping on autotranslating guests
  pvcalls-back: do not return error on inet_accept EAGAIN
  xen-netfront: Fix race between device setup and open
  xen/grant-table: Use put_page instead of free_page
  x86/xen: init %gs very early to avoid page faults with stack protector

1 files changed, 24 insertions, 22 deletions

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 9bd7ddeeb6a5..8328d395e332 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -351,6 +351,9 @@ static int xennet_open(struct net_device *dev)
 	unsigned int i = 0;
 	struct netfront_queue *queue = NULL;
 
+	if (!np->queues)
+		return -ENODEV;
+
 	for (i = 0; i < num_queues; ++i) {
 		queue = &np->queues[i];
 		napi_enable(&queue->napi);
@@ -1358,18 +1361,8 @@ static int netfront_probe(struct xenbus_device *dev,
 #ifdef CONFIG_SYSFS
 	info->netdev->sysfs_groups[0] = &xennet_dev_group;
 #endif
-	err = register_netdev(info->netdev);
-	if (err) {
-		pr_warn("%s: register_netdev err=%d\n", __func__, err);
-		goto fail;
-	}
 
 	return 0;
-
- fail:
-	xennet_free_netdev(netdev);
-	dev_set_drvdata(&dev->dev, NULL);
-	return err;
 }
 
 static void xennet_end_access(int ref, void *page)
@@ -1737,8 +1730,6 @@ static void xennet_destroy_queues(struct netfront_info *info)
 {
 	unsigned int i;
 
-	rtnl_lock();
-
 	for (i = 0; i < info->netdev->real_num_tx_queues; i++) {
 		struct netfront_queue *queue = &info->queues[i];
 
@@ -1747,8 +1738,6 @@ static void xennet_destroy_queues(struct netfront_info *info)
 		netif_napi_del(&queue->napi);
 	}
 
-	rtnl_unlock();
-
 	kfree(info->queues);
 	info->queues = NULL;
 }
@@ -1764,8 +1753,6 @@ static int xennet_create_queues(struct netfront_info *info,
 	if (!info->queues)
 		return -ENOMEM;
 
-	rtnl_lock();
-
 	for (i = 0; i < *num_queues; i++) {
 		struct netfront_queue *queue = &info->queues[i];
 
@@ -1774,7 +1761,7 @@ static int xennet_create_queues(struct netfront_info *info,
 
 		ret = xennet_init_queue(queue);
 		if (ret < 0) {
-			dev_warn(&info->netdev->dev,
+			dev_warn(&info->xbdev->dev,
 				 "only created %d queues\n", i);
 			*num_queues = i;
 			break;
@@ -1788,10 +1775,8 @@ static int xennet_create_queues(struct netfront_info *info,
 
 	netif_set_real_num_tx_queues(info->netdev, *num_queues);
 
-	rtnl_unlock();
-
 	if (*num_queues == 0) {
-		dev_err(&info->netdev->dev, "no queues\n");
+		dev_err(&info->xbdev->dev, "no queues\n");
 		return -EINVAL;
 	}
 	return 0;
@@ -1828,6 +1813,7 @@ static int talk_to_netback(struct xenbus_device *dev,
 		goto out;
 	}
 
+	rtnl_lock();
 	if (info->queues)
 		xennet_destroy_queues(info);
 
@@ -1838,6 +1824,7 @@ static int talk_to_netback(struct xenbus_device *dev,
 		info->queues = NULL;
 		goto out;
 	}
+	rtnl_unlock();
 
 	/* Create shared ring, alloc event channel -- for each queue */
 	for (i = 0; i < num_queues; ++i) {
@@ -1934,8 +1921,10 @@ abort_transaction_no_dev_fatal:
 	xenbus_transaction_end(xbt, 1);
  destroy_ring:
 	xennet_disconnect_backend(info);
+	rtnl_lock();
 	xennet_destroy_queues(info);
  out:
+	rtnl_unlock();
 	device_unregister(&dev->dev);
 	return err;
 }
@@ -1965,6 +1954,15 @@ static int xennet_connect(struct net_device *dev)
 	netdev_update_features(dev);
 	rtnl_unlock();
 
+	if (dev->reg_state == NETREG_UNINITIALIZED) {
+		err = register_netdev(dev);
+		if (err) {
+			pr_warn("%s: register_netdev err=%d\n", __func__, err);
+			device_unregister(&np->xbdev->dev);
+			return err;
+		}
+	}
+
 	/*
 	 * All public and private state should now be sane.  Get
 	 * ready to start sending and receiving packets and give the driver
@@ -2150,10 +2148,14 @@ static int xennet_remove(struct xenbus_device *dev)
 
 	xennet_disconnect_backend(info);
 
-	unregister_netdev(info->netdev);
+	if (info->netdev->reg_state == NETREG_REGISTERED)
+		unregister_netdev(info->netdev);
 
-	if (info->queues)
+	if (info->queues) {
+		rtnl_lock();
 		xennet_destroy_queues(info);
+		rtnl_unlock();
+	}
 	xennet_free_netdev(info->netdev);
 
 	return 0;