igb(4) promiscuous mode bug.

[Ian Freislich]

Hi

It appears that the igb(4) driver or hardware doesn't correctly
handle 802.1Q frames when placed in promiscuous mode if vlanhwtag
is enabled.  The NIC omits to tag and untag the frames when placed
in promiscuous mode.

The following output shows the bridge address table on the connected
switch with the 4 NICs (82575GB) with and without vlan hardware
assistance enabled.  The interfaces are placed in promiscuous mode
by the carp(4) driver.

With hwtag in promiscuous mode:
sw3.cab10# sh bridge address-table port-channel 1
Aging time is 300 sec

  Vlan        Mac Address       Port     Type    
-------- --------------------- ------ ---------- 
   1       00:1b:21:1f:01:00    ch1    dynamic   
   1       00:1b:21:1f:01:01    ch1    dynamic   
   1       00:1b:21:1f:01:04    ch1    dynamic   
   1       00:1b:21:1f:01:05    ch1    dynamic   


Without hwtag in promiscuous mode:
sw3.cab10# sh bridge address-table port-channel 1
Aging time is 300 sec

  Vlan        Mac Address       Port     Type    
-------- --------------------- ------ ---------- 
   1       00:1b:21:1f:01:00    ch1    dynamic   
   1       00:1b:21:1f:01:01    ch1    dynamic   
   1       00:1b:21:1f:01:04    ch1    dynamic   
   1       00:1b:21:1f:01:05    ch1    dynamic   
   2       00:1b:21:1f:01:00    ch1    dynamic   
   3       00:1b:21:1f:01:00    ch1    dynamic   
   4       00:1b:21:1f:01:00    ch1    dynamic   
   5       00:1b:21:1f:01:00    ch1    dynamic   
   6       00:1b:21:1f:01:00    ch1    dynamic   
   7       00:1b:21:1f:01:00    ch1    dynamic   
   9       00:1b:21:1f:01:00    ch1    dynamic   
   14      00:1b:21:1f:01:00    ch1    dynamic   
   19      00:1b:21:1f:01:00    ch1    dynamic   
   20      00:1b:21:1f:01:00    ch1    dynamic   
   21      00:1b:21:1f:01:00    ch1    dynamic   
   23      00:1b:21:1f:01:00    ch1    dynamic   
   25      00:1b:21:1f:01:00    ch1    dynamic   
   26      00:1b:21:1f:01:00    ch1    dynamic   
   27      00:1b:21:1f:01:00    ch1    dynamic   

Ian

--
Ian Freislich