r360902 breaks VLAN interface on if_em (82579LM)

[Lev Serebryakov]

Hello Ian,

Thursday, May 28, 2020, 2:45:48 AM, you wrote:

> I noticed that my VLAN interfaces stopped working after a recent build. 
> tcpdump showed traffic leaving leaving and entering the interface but no 
> host on the network actually received any packets from this host.  A 
> binary search led me to r360902 and indeed the following change fixed 
> the issue for me:
 Problem is, this change will return terrible situation when adding new VLAN
will flap connection status.

 It all worked before iflib: hardware VLAN filtering worked, and
adding/removing new VLAN didn't cause link to flap.

 Now, with iflib, looks like we can not have all good things at once :(

-- 
Best regards,
 Lev                            mailto:lev at FreeBSD.org