hv_netvsc: fix bonding devices check in netvsc_netdev_event()

Bonding driver sets IFF_BONDING on both master (the bonding device) and
slave (the real NIC) devices and in netvsc_netdev_event() we want to skip
master devices only. Currently, there is an uncertainty when a slave
interface is removed: if bonding module comes first in netdev_chain it
clears IFF_BONDING flag on the netdev and netvsc_netdev_event() correctly
handles NETDEV_UNREGISTER event, but in case netvsc comes first on the
chain it sees the device with IFF_BONDING still attached and skips it. As
we still hold vf_netdev pointer to the device we crash on the next inject.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 62a4e6e3c63ed1aad4d4e1c6fb67245b51450628..3ba29fc80d057e744eef4ae98ad60315f742c4ce 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1482,8 +1482,13 @@ static int netvsc_netdev_event(struct notifier_block *this,
 {
        struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
 
-       /* Avoid Vlan, Bonding dev with same MAC registering as VF */
-       if (event_dev->priv_flags & (IFF_802_1Q_VLAN | IFF_BONDING))
+       /* Avoid Vlan dev with same MAC registering as VF */
+       if (event_dev->priv_flags & IFF_802_1Q_VLAN)
+               return NOTIFY_DONE;
+
+       /* Avoid Bonding master dev with same MAC registering as VF */
+       if (event_dev->priv_flags & IFF_BONDING &&
+           event_dev->flags & IFF_MASTER)
                return NOTIFY_DONE;
 
        switch (event) {