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

Jari Aalto
2008-08-24T15:08:59Z

Krzysztof Halasa <khc@pm.waw.pl> writes:

> Jari Aalto <jari.aalto@cante.net> writes:
>
>>>From Debian stock kernel:
>>
>> $ grep -Ei 'iommu|agp' /boot/config-2.6.25-2-amd64
>> CONFIG_GART_IOMMU=y
>> CONFIG_CALGARY_IOMMU=y
>> CONFIG_CALGARY_IOMMU_ENABLED_BY_DEFAULT=y
>> CONFIG_IOMMU_HELPER=y
>> CONFIG_AGP=y
>> CONFIG_AGP_AMD64=y
>> CONFIG_AGP_INTEL=m
>> CONFIG_AGP_SIS=m
>> CONFIG_AGP_VIA=m
>
> Should be fine. SWIOTLB is there for a backup, most (?) Intel machines
> don't have IOMMU (even the newest desktop boards).
>
>> Are these the correct boot options, without swiotlb?
>>
>> iommu=noagp,noaperture,off
>>
>> Or just:
>>
>> iommu=off
>
> Do you have problems without "iommu=XXX"?

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?

Thanks,
Jari