Subject: Re: [RFC] ethtool semantics

From: Bill Davidsen <[email-masked]>
Date: Wed, 09 Jun 2004 17:09:04 -0400

Roger Luethi wrote:
> On Mon, 07 Jun 2004 14:57:23 -0700, David S. Miller wrote:
> 
>>On Mon, 7 Jun 2004 23:28:04 +0200
>>Roger Luethi <[email-masked]> wrote:
>>
>>
>>>What is the correct response if a user passes ethtool speed or duplex
>>>arguments while autoneg is on? Some possible answers are:
>>>
> 
> [...]
> 
>>speed and duplex fields should be silently ignored in this case
> 
> 
> It may not matter much because few people care about forced media these
> days. And it is debatable whether trying to guess the users intention
> is a good idea (we lack means for users to manipulate autoneg results
> via advertisted values but that's no big deal).

It does sometimes matter, because even these days we sometimes see a 
case where a brand name switch (like Cisco) and a brand name card 
(Intel, 3COM) negotiate but just don't "work right" later. In those 
cases forcing on both ends or just the NIC end results in a fully 
functional connection.

We usually do this with module parameters, but do use ethtool (or 
mii-tool) on occasion.

> 
> However, "silently ignoring" strikes me as a very poor choice, in
> stark contrast to Unix/Linux tradition. A user issues a command which
> cannot be executed and gets the same response that is used to indicate
> success!? What school of user interface design is that? How is that
> not confusing users? </rant>

Yah.

Seeing this happen while autonegotiation is in progress is a small and 
unlikely window of course!

-- 
    -bill davidsen ([email-masked])
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me