Bug: Asus CUR-DLS and 2.6

Mark Felder
2006-09-24T02:19:38Z

Hello all,

I'm writing to report and interesting occurance that I fully believe is a bug
in the 2.6 kernel.

In March I purchased a used Asus CUR-DLS motherboard with two socket 370 PIII
866 processors. I picked up two 256MB PC-133 ECC modules. I proceeded
installed Linux on it and all was well. I believe my initial kernel was
approximately 2.6.12.

At the end of May, things went awry. The machine had an interesting issue --
it would beep 3 times, and then it would be hardlocked. I didn't have much
time to test the machine out as it was only a for-fun machine and I had
started a new job.

Well, I have more free time now, and I've narrowed down the bug I think.
Here's the situation:

With a 2.6.15 and 2.6.16 kernel on Gentoo I would receive 3 beeps and it would
hardlock as I expained. The CPU fans shut off -- there's no hope of bringing
it out of this. Rarely it's happened at GRUB or before GRUB, but only when
I've been working on this for a long period of time.

I've tried many live CDs -- most use recent 2.6 kernels, and I could repeat
nearly the same problem on them. It often occurs when starting networking.
I've tried onboard e100, tulip, and others that I have access to and I get
nearly the same results. Depending on the livecd I can either get a hardlock
+ 3 beeps, or I can receive an address via DHCP, but I can't speak to the
network at all. The e100 reports "system timing errors" in this occasion. On
some setups I can reproduce it instantly by having the network cable
unplugged and plugging it in after it's brought up the e100 interface.

Now I was under the inital impression that I had bad hardware. I've
thouroughly tested my RAM and even replaced the motherboard with an identical
ASUS CUR-DLS, so right now I have two of them on my hands, and the one I just
got has the most recent BIOS, the other did not. The only hardware bug that I
can see is that one processor incorrectly reports its temperature -- stays
around 50 celcius all the time, but I figure that's just a bad sensor.

I came to the conclusion it must be a 2.6 bug when I dropped in a Slackware CD
I just picked up recently. It uses a 2.4 kernel. To my surprise it worked
fine -- no hardlocks, network works great on all adapters, including onboard.
Very strange stuff indeed.

Things I've tried with the 2.6 include apic/noapic, nosmp and swapped
processors to each other's slots, nolapic (dont think it actually works for
SMP though, I'm not sure on that one), and nearly every combination of them.
The only other thing I've noticed is that some livecds report an apic but
when initializing the kernel -- right at the very beginning, and it says to
report them to the hardware manufacturer and it claims to work around it.

This motherboard uses the Serverworks chipset. I'm not using SCSI.

I would really like to get this bug squashed -- I have a use for this system
and I'd really really prefer to use a 2.6 kernel. Now since I have an
identical motherboard on hand, if anyone is interested in figuring out what
is going on and would like hands on access to the hardware, I could get you
one of these motherboards. If you really don't have access to PIII's/RAM to
put in it, I could the whole setup off too, but I'd really like to get it
back if possible.

I'm open to any suggestions you might have. As of this moment, I'm not on the
kernel mailing list, but I will be looking to sign up after I send this off.

Thank you for your time, and keep up the great work everyone :)

Mark Felder