Go back to switching datapath directly in the notifier callback.
Otherwise datapath might not get switched on unregister.
No need for calling the NOTIFY_PEERS notifier since that is only for
a gratitious ARP/ND packet; but that is not required with Hyper-V
because both VF and synthetic NIC have the same MAC address.
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Fixes: 02e633075a17 ("netvsc: transparent VF management") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>