Re: NE2000 lockup in 2.0.0?

Paul Gortmaker (gpg109@rsphy1.anu.edu.au)
Fri, 14 Jun 1996 19:43:30 +1000 (EST)


- From "Marek Michalkiewicz" at Jun 14, 96 03:45:37 am

> The 2.0.0 kernel works quite well, but I just had one lockup.

Did you hit any of the magic <Scroll-Lock> combinations to see
if there was any life left in the kernel still?

> I suspect that it might be caused by my cheap old NE2000 clone
> (Genius GE-2000, built in 1993, a fairly large card with many
> chips on it, not one of these new single-chip cards).
>
> The card has two LEDs on the back: a green one for "power on" and
> a red one for "network activity". The system locked up solid, no
> messages, no VC switching. There was only very little network
> activity at that time. I suspect the card because NE2000 clones
> were known to cause problems in the past, and the red LED on the

Causing problems in the past is not a good reason to point the
finger at it now. The driver used to do bad things back in early
1.2.x releases which caused hangs but that has long since been fixed.
People just like to keep dragging that skeleton out of the closet...

> card (which is normally flashing randomly) was illuminated all
> the time (even after disconnecting the T connector from the card).

If the kernel hangs *anywhere*, it will stop servicing interrupts
from the card, and the card will then overrun and the 8390 will
automatically stop. So it is not so surprising that the LED
stops blinking.

> Note that it happened once so far (it worked fine for several
> days with various 1.99.x kernels as well as 2.0.0), so it could
> just be a random hardware problem. Especially since I run my
> ISA bus at 40/3 = 13.3 MHz (is it possible for a NE2000 to lock
> up because of too fast ISA bus speed?).

All sorts of things are possible if hardware is driven beyond its
capabilities. Most ne2k clone cards can handle 10, 11, 13 and sometimes
even 16MHz. However, if you even think you are experiencing trouble
resulting from any ISA card, you should play it safe and run at 8MHz
when maximum reliablility is an issue.

> I'm reporting it just in case it turns out to be a real bug...
> Or is the NE2000 such a bad design that it is impossible to
> guarantee no lockups no matter how careful is the driver?

This bit of folklore is almost as bad as the "Blue Star LSD Tattos"
that has just resurfaced on usenet for the zillionth time. The design
shows its age of nearly ten years, but regardless people are actually
still making ISA and even PCI NE2000 clones today. There are many
other cards out there that out-qualify the ne2k for the most Broken As
Designed card.

Paul.