Re: Fwd: Kernel DHCP unpredictable/fails (PXE boot), userspace DHCP works just fine

Eugene Grosbein <eugen@grosbein.net> ezt írta (időpont: 2023. márc. 19., V,
0:16):

> 19.03.2023 5:01, Attila Nagy wrote:
>
> >     Sometimes UEFI/BIOS SETUP has some settings for ACPI/HPET timers
> (enable/disable),
> >     did you try "playing" with such options?
> >
> > Nope, I haven't thought about that.
> > It's enabled (default setting).
>
> Another possible reason: DHCP packets sent from DHCP client have 1-bit
> flag indicating
> if client wants to receive an answer as unicast or broadcast UDP packet.
>
> You could try hacking source to force broadcasts and see if that changes
> things.
> This NIC's driver has previous history of bad in-chip filtering packets in
> transit
> from the wire to the host (CPU).
>
Thanks a lot for the great ideas!
Although if I follow the code right, this is already set:
https://github.com/freebsd/freebsd-src/blob/c3179891f897d840f578a5139839fcacb587c96d/sys/nfs/bootp_subr.c#L1246

If you have the time to take a look at my patched kernel outputs, I think
the response datagrams get to the UDP stack. What I feel is either they
doesn't make it to the soreceive call sometimes or the whole process gets
reset for some reason.