[PATCHv1 net] xen-netback: transition to CLOSED when removing a VIF

[David Vrabel <david.vrabel@citrix.com>]

From: David Vrabel <david.vrabel@citrix.com>

If a guest is destroyed without transitioning its frontend to CLOSED,
the domain becomes a zombie as netback was not grant unmapping the
shared rings.

When removing a VIF, transition the backend to CLOSED so the VIF is
disconnected if necessary (which will unmap the shared rings etc).

This fixes a regression introduced by
279f438e36c0a70b23b86d2090aeec50155034a9 (xen-netback: Don't destroy
the netdev until the vif is shut down).

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Paul Durrant <Paul.Durrant@citrix.com>
---
 drivers/net/xen-netback/xenbus.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index b45bce2..1b08d87 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -39,11 +39,15 @@ static int connect_rings(struct backend_info *);
 static void connect(struct backend_info *);
 static void backend_create_xenvif(struct backend_info *be);
 static void unregister_hotplug_status_watch(struct backend_info *be);
+static void set_backend_state(struct backend_info *be,
+			      enum xenbus_state state);
 
 static int netback_remove(struct xenbus_device *dev)
 {
 	struct backend_info *be = dev_get_drvdata(&dev->dev);
 
+	set_backend_state(be, XenbusStateClosed);
+
 	unregister_hotplug_status_watch(be);
 	if (be->vif) {
 		kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
-- 
1.7.2.5