Subject: Re: E1000E/82567LM-3: link reported up too soon

From: [email-masked] (Arnaud Ebalard)
Date: Wed, 15 Sep 2010 17:34:30 +0200

Hi Brian,

Brian Haley <[email-masked]> writes:

>> <snip>
>> 
>> I tested it with 2 different 100M/s switches (Cisco Catalyst 2960 and a
>> Planex FX08-Mini) so I guess the switch is not the root of the issue. I
>> came to the conclusion that the link is reported up too soon by the
>> driver.
>> 
>> Because the first packets are losts, the result is that address
>> autoconfiguration is delayed by a few seconds as can be seen on
>> following capture on the laptop:
>
> I've seen similar things on various NICs,

I remember I add the same kind of issue on a broadcom chip on a dell
D600 but had no time to investigate at that time. Did you notice the
problem for different brands? Do you think those are driver-related
issues or something in common code?
 
> posted a patch last week that unfortunately had other bad
> side-effects.  When I have time I'll work on it again, but I'd also be
> curious if there's something that can be done at the driver level to
> help out, since it seemed like part of the problem is that the link-UP
> came before the device was actually able to transmit packets, so the
> DAD was lost.

I am not familiar with e1000e code but as I said previously I'd be happy
to test patches to help determine precisely where the packet gets lost
and why.

Cheers,

a+