10 GB in Opteron machine

[Christoph Pleger <Christoph.Pleger@uni-dortmund.de>]

Hello,

I had a working kernel configuration for an Opteron machine. Since that
configuration was supposed to support many kinds of hardware, it
contained many settings that were not optimal for an Opteron machine. So
I created a new configuration especially for that machine. But the
resulting kernel could not be booted. To find the problem I took the
working configuration and changed and it in many small steps and after
every change compiled the kernel, installed it and rebooted to see if
the kernel still boots. 

At last I found out that setting HIGHMEM support to 64 GB is the
problem. But is it really not possible to use more than 4GB on an
Opteron machine?

I have set the processor type to Opteron and disabled SMP support. I am
using Kernel 2.6.11.12.

Christoph