Re: 2.6.25 DMA: Out of SW-IOMMU space - Asus M2N32 AMD 8GB memory

Gerardo Exequiel Pozzi
2008-08-29T03:48:37Z

Hi

(sorry my english)

When booted kernel with no iommu parameter, it uses the iommu gart (from amd) and the size of the aperture is 64MB
You can try to grow this size with iommu=memaper=2 for 128MB or 3 for 256MB. I don't have experience with this, but
i read that this, solves the problem.

I have the similar hardware, but when boot in 64 bits, limit the memory with mem=4G (discarded 0.5G that are (remaped from pci space) beyond 4G)
and iommu=noaperture. (This is not option for you, will be discard 4G of RAM)

Asus M2N32-SLI DELUXE (BIOS Phoenix ver 1603 [12/17/2007])
4 x 1GB OCZ DDR2 PC2-6400 Platinum Rev2 ( OCZ2P800R21G )
AMD Athlon 64 X2 5200+ ( ADA5200IAA6CS ) (stepping F2)

I have realiced some test an posted here (sorry in spanish): http://www.pcmasmas.com/viewtopic.php?t=31445

Buena suerte.

Jari Aalto <jari.aalto <at> cante.net> writes:

> Initially when the PC was installed (and had no IOMMU) options, that
> cause the whole harddisk to corrupt and I had to reinstall everything.
> It might have been a little older kernel (2.6.23?), but I don't recall
> it exactly.

> According to messages in syslog I tried to track down similar incidents
> and found the iommu articles. But the information was like trial and
> error.

> Would you suggest that "immu=off" would be best option?

--
Gerardo Exequiel Pozzi ( djgera )
http://www.djgera.com.ar
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