sfc: don't insert mc_list on low-latency firmware if it's too long
If the mc_list is longer than 256 addresses, we enter mc_promisc mode.
If we're in mc_promisc mode and the firmware doesn't support cascaded
multicast, normally we also insert our mc_list, to prevent stealing by
another VI. However, if the mc_list was too long, this isn't really
helpful - the MC groups that didn't fit in the list can still get
stolen, and having only some of them stealable will probably cause
more confusing behaviour than having them all stealable. Since
inserting 256 multicast filters takes a long time and can lead to MCDI
state machine timeouts, just skip the mc_list insert in this overflow
condition.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed