Mailinglist Archive: opensuse-amd64 (130 mails)

[Andi Kleen <ak@xxxxxxx>]

On Mon, 15 Sep 2003 17:54:55 +0200
Kees Hoekzema <kees@xxxxxxxxxxxx> wrote:


> 
> > If any info is needed on the LSI 320-4x on an TYAN S2880 with 2 procs and
> > 6GB DDR, I should be able to tell soon.
> Well, I would be very much interested if it is going to work for you, because 
> i'm already thinking of removing 2GB and put the server into production 
> (after a few more stability tests ofcourse ;))
> 
> I also mailed with someone from AMD, he said he never heard of problems with 
> >4GB, which is strange, because on this list I see multiple people having 
> that problem.


In theory it could be a driver issue. When the drivers do not support 64bit addresses
on the bus the kernel has to use the IOMMU code to remap buffers to 
32bit as needed.

This code is only enabled when you use >4GB. But at least the LSI should
support 64bit addresses. 

In theory it is possible that they have some IOMMU related bug though.
The driver has to use special APIs for it.

I usually run my boxes with forced IOMMU mode (iommu=force) to catch this 
early, but we haven't had problems with this in a long time.

You could check it e.g. by booting with less than 4GB and setting iommu=force.
If that also causes lockups (and without forcing it runs stable with <=4GB)
then it is likely a driver issue.

To rule out hardware issues I would physically remove the DIMMs, not just
boot with mem=4GB

-Andi