FreeBSD 12.1 have different version of mlx5en driver with release 3.5.2/Sep.2019 from FreeBSD 12.0 version 3.4.2/July.2018
On brand new HP ProLiant XL170r Gen10 with two Mellanox 10/25G HP cards.
I saw big issue with forwarding packets. They don't pass out over the cables.
You can see that they going out with tcpdump on interface, but really they don't sending to destination!
After observing and debugging at entire process from hardware,firmwares on it, network stack till mlx5e_xmit path in the new mlx5 driver. I made replacement of new driver with old one in my local kernel tree. Now it works fine!
I think you need to apply r354440 to fix the problem.
Yes, this is a known issue. Try a 12-stable kernel!
I can confirm that patch works fine were you do update of FBSD to 12-STABLE.
P.S. If you are with 12.1 sources. It isn't enough to append just checking about csum_flags & CSUM_SND_TAG, cause CSUM_SND_TAG isn't defined in FBSD 12.1 sources at all.
Are you using freebsd-update or are you using svn ?
I using current branch for development purposes.
For production servers I using only binary update with freebsd-update tool.
I'm not happy to make custom setups because have lot of production servers across of world.
If I take steps on road to make separate version of FreeBSD which can be replacement for prod.servers. This will cost efforts to me to support it!
I see. Maybe this issue can be assigned to firstname.lastname@example.org .
The 11-release and 12-release branches are froozen from what I understand.
(In reply to Hans Petter Selasky from comment #6)
They will likely point you towards https://www.freebsd.org/security/errata-template.txt -> it's relevant straightforward; fill it out and send it to secteam@ for consideration. I suspect additionally a diff against releng/12.1 would be appreciated as well since it sounds like it doesn't quite apply cleanly, but I do not know their requirements here.
OK, I'll try to do submit a request for a MFS first and see what "so@" says.
You'll see a message here once the issue gets fixed via freebsd-update .
Thank you for your patience!