[VLAN]: Fix early vlan adding leads to not functional device

OK, I can see what's happening here. eth0 doesn't detect link-up until
after a few seconds, so when the vlan interface is opened immediately
after eth0 has been opened, it inherits the link-down state. Subsequently
the vlan interface is never properly activated and are thus unable to
transmit any packets.

dev->state bits are not supposed to be manipulated directly. Something
similar is probably needed for the netif_device_present() bit, although
I don't know how this is meant to work for a virtual device.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 0 deletions

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index 1f6d31670bc7..91e412b0ab00 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -578,6 +578,14 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
                         if (!vlandev)
                                 continue;
 
+                        if (netif_carrier_ok(dev)) {
+                                if (!netif_carrier_ok(vlandev))
+                                        netif_carrier_on(vlandev);
+                        } else {
+                                if (netif_carrier_ok(vlandev))
+                                        netif_carrier_off(vlandev);
+                        }
+
                         if ((vlandev->state & VLAN_LINK_STATE_MASK) != flgs) {
                                 vlandev->state = (vlandev->state &~ VLAN_LINK_STATE_MASK) 
                                         | flgs;