If bridge is configured with no STP and forwarding delay of 0 (which
is typical for virtualization) then when link starts it will flood all
packets for the first 20 seconds.
This bug was introduced by a combination of earlier changes:
* forwarding database uses hold time of zero to indicate
user wants to always flood packets
* optimzation of the case of forwarding delay of 0 avoids the initial
timer tick
The fix is to just skip all the topology change detection code if
kernel STP is not being used.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4f0611af47