# HG changeset patch
# User gcosta@xxxxxxxxxx
# Date 1166107279 18000
# Node ID ddab7c52fc80ffa867df2eaa99c9af2b4b4383a9
# Parent  35c724302bdd1339e17dad43085c841917a5dd88
[LINUX] Prevent closing netfront in double state change

If it happens for xenbus to deliver a Closing change state for
whatever reason, frontend will try to unregister already-unregistered
structures, leading guest to BUG()

Signed-off-by: Glauber de Oliveira Costa <gcosta@xxxxxxxxxx>

diff -r 35c724302bdd -r ddab7c52fc80 linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c
--- a/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c	Thu Dec 14 11:09:27 2006 +0000
+++ b/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c	Thu Dec 14 09:41:19 2006 -0500
@@ -532,7 +532,10 @@ static void backend_changed(struct xenbu
 		break;
 
 	case XenbusStateClosing:
-		netfront_closing(dev);
+		if (dev->state != XenbusStateClosed)
+			netfront_closing(dev);
+		else
+			WPRINTK("Ignoring Closing request after already Closed");
 		break;
 	}
 }