On Sun, Jun 12, 2005 at 03:29:50PM -0400, Jacob Martin wrote:
> Hardware memhole mapping never seems to work, or causes lockups right away.  I 
> need to test it further though.
> 
> I have discovered that with the following features enabled:
> 
> 1.  Software memhole mapping
> 2.  Continuous,
> 
> linux sees the entire 4GB of memory.  However, when things start getting 
> requested from the upper half, there are Oopses generated.  Attached are two 
> Oopses that occurred under the test scenario described.  

What happens when you boot with numa=off or with numa=noacpi ? 

The system seems to believe it has memory in an area not covered
by mem_map.


> launch big memory apps.
> 
> I suppose I could write a program to consume/probe the upper memory half.  
> Anyone know of a good/quicky way to do that?  

You can use the attached program which I often use for similar purposes.
It writes nearly all free memory in a loop and also often triggers memory 
problems.

-Andi