iommu: Clean up after a failed bus initialization

Make sure we call the ->remove_device call-back on all
devices already initialized with ->add_device when the bus
initialization fails.
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/iommu.c

@@ -753,6 +753,17 @@ static int add_iommu_group(struct device *dev, void *data)
 	return ops->add_device(dev);
 }
 
+static int remove_iommu_group(struct device *dev, void *data)
+{
+	struct iommu_callback_data *cb = data;
+	const struct iommu_ops *ops = cb->ops;
+
+	if (ops->remove_device && dev->iommu_group)
+		ops->remove_device(dev);
+
+	return 0;
+}
+
 static int iommu_bus_notifier(struct notifier_block *nb,
 			      unsigned long action, void *data)
 {
@@ -821,19 +832,25 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
 	nb->notifier_call = iommu_bus_notifier;
 
 	err = bus_register_notifier(bus, nb);
-	if (err) {
-		kfree(nb);
-		return err;
-	}
+	if (err)
+		goto out_free;
 
 	err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
-	if (err) {
-		bus_unregister_notifier(bus, nb);
-		kfree(nb);
-		return err;
-	}
+	if (err)
+		goto out_err;
+
 
 	return 0;
+
+out_err:
+	/* Clean up */
+	bus_for_each_dev(bus, NULL, &cb, remove_iommu_group);
+	bus_unregister_notifier(bus, nb);
+
+out_free:
+	kfree(nb);
+
+	return err;
 }
 
 /**