Subject: Re: Panic in latest -current with fxp0
To: Bill Sommerfeld <>
From: Johan Danielsson <>
List: current-users
Date: 11/19/1999 17:05:58
Bill Sommerfeld <> writes:

> my impression was that "tri-state" means that the output is
> floating, and i'd be concerned that this might occasionally be read
> as a zero on a bad day due to electrical noise.

I think it's pull-up. Can anyone confirm or deny this?

> i'd look harder at what other drivers do in this case.  (is there
> anything useful in, for instance, the FreeBSD PAO distribution?)

PAO doesn't support CardBus at all (as far as I know). FreeBSD-stock
uses the same fxp driver as we do.

Linux does EEPROM checksum, but there isn't any documentation on this
checksum anyware that I've seen (appart from the Linux source). I
haven't seen any other source code.

> In particular, panic'ing in the attach routine because hardware is
> not all there is pretty unfriendly; it's better for the driver to
> complain vigorously via printf and then not actually attach the
> device.. if this is due to a driver bug, it's unfriendly to force
> someone to open the box and unplug the card before they can reboot
> to rebuild a new kernel.  (and, for instance, on my laptop, the fxp
> is not removable..)

I fully agree with this.

>  a) gripe if the eeprom autosize doesn't give you anything
>  sane-looking.

It does that now.

>  b) gripe if you read out a bogus MAC address (e.g., one with either
> or both of the broadcast/multicast bit or the "not globally unique"
> bit set).

Worth considering.