netpoll: prevent netpoll setup on slave devices

In commit 8d8fc29 (netpoll: disable netpoll when enslave a device), we automatically disable netpoll when the underlying device is being enslaved, we also need to prevent people from setuping netpoll on devices that are already enslaved. Signed-off-by: WANG Cong <[email protected]> Signed-off-by: David S. Miller <[email protected]>
goeke · Jun 9, 2011 · 0c1ad04 · 0c1ad04
1 parent fe6fe79
commit 0c1ad04
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
@@ -792,6 +792,12 @@ int netpoll_setup(struct netpoll *np)
 		return -ENODEV;
 	}
 
+	if (ndev->master) {
+		printk(KERN_ERR "%s: %s is a slave device, aborting.\n",
+		       np->name, np->dev_name);
+		return -EBUSY;
+	}
+
 	if (!netif_running(ndev)) {
 		unsigned long atmost, atleast;