Re: PROBLEM: OOPSes in PREEMPT SMP for AMD Opteron Dual-Core with Memhole Mapping (non tainted kernel)

[Jacob Martin <martin@cs.uga.edu>]

> I think it has or the strange software memhole (what is that?)
> From your oopses i more suspect it is hardware actually:
> > Jun  7 14:11:27 optimator Unable to handle kernel paging request at
> > 00000000000025b0 RIP: Jun  7 14:11:27 optimator
> > <ffffffff8016797a>{pte_alloc_map+170}
>
> It crashes on first accessing newly allocated memory for page tables.

> Most likely something is wrong with your memory or memory map.
> Maybe it is related to your "discrete mtrr mapping" or your "software
> memhole" whatever they are? I would suggest to try without these.


	There are three options for Memhole mapping in my BIOS:  Disabled, Hardware, 
and Software.  I really don't know why there would be a "software" option, or 
what it does.  Also, I'm not sure what the difference between continuous and 
discrete MTRR mapping is.  The BIOS says it has to do with some linux 
kernels, but I haven't found any reliable information about it.

I disabled Memhole mapping and PREEMPT entirely.  I'll try to stress test out 
some more oopses.  I'll also memtest86 all of the memory.

Thanks for the help,
Jake Martin