Re: PR 1591: if_infiniband: Support BPF write for broadcast frames

Having heard no objections, I went ahead and committed this fix:

https://cgit.freebsd.org/src/commit/?id=8d079c6a9a5dfdc75adaf9bc31f2ee8111b849a1

Thanks,

Ravi (rpokala@ , wearing my Vdura hat)

-----Original Message-----
From: Ravi Pokala <[email protected] <mailto:[email protected]>>
Date: Monday, February 10, 2025 at 17:13
To: <[email protected] <mailto:[email protected]>>, "Dance, Nick" <[email protected] <mailto:[email protected]>>
Subject: PR 1591: if_infiniband: Support BPF write for broadcast frames

> Hi folks,
> 
> Vdura (you might know of us as Panasas; we renamed ourselves last year) is starting to use InfiniBand on our FreeBSD-based platforms. One of our first issues was getting DHCP to work with InfiniBand, because we use DHCP for not just assigning addresses, but also for passing other configuration information using the standard mechanism for optional data.
> 
> A Linux IP-over-IB client was able to send DHCDISCOVER, and our FreeBSD server was able to set up BPF and receive it. But when the server tried to send an ARP to make sure that the address it wanted to DHCPOFFER was available, nothing went over the wire. It turns out that if_infiniband interfaces don't transmit link-layer broadcasts.
> 
> My colleague Nick was able to solve this, and the rest of the bring-up went smoothly. The fix passes muster internally, but we were hoping to get some more eyes on it before committing it to the main repo.
> 
> If anyone wants to take a look: https://github.com/freebsd/freebsd-src/pull/1591
> 
> If I don't hear any objections by the end of the week, I'll go ahead and submit it.
> 
> Thanks,
> 
> Ravi (rpokala@ , wearing my Vdura hat)