On Fri, 24 Dec 2004, Bogdan Costescu wrote:

- the combination of x86_64 kernel, sata_sil and the Hitachi disks is
not good; the corruption seems to appear while writting to disk.  

I've gotten some more inspiration just after I sent the message...

The Sil3114 appears on the PCI bus as a 32-bit 66MHz device, therefore
it should use IOMMU with >4Gb RAM. Booting the x86_64 kernel with
"mem=2048m" makes the corruption go away; the difference is that the
IOMMU is automatically disabled by the kernel:

PCI-DMA: Disabling IOMMU.

With 8Gb, there is an error related to IOMMU:

Checking aperture...
CPU 0: aperture @ 1ee0000000 size 32768 KB
Your BIOS doesn't leave a aperture memory hole
Please enable the IOMMU option in the BIOS setup
Mapping aperture over 65536 KB of RAM @ 8000000

The IOMMU was indeed disabled in BIOS. I enabled it and gave the
aperture several sizes, but the IOMMU message from the kernel is the
same. Checking back logs backups, I have always obtained this message
related to IOMMU, while the non-lba48 Maxtor disk worked fine for
several months and still works.

So, is there any link between IOMMU and lba48 ?

-- 
Bogdan Costescu

IWR - Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen
Universitaet Heidelberg, INF 368, D-69120 Heidelberg, GERMANY
Telephone: +49 6221 54 8869, Telefax: +49 6221 54 8868
E-mail: Bogdan.Costescu@IWR.Uni-Heidelberg.De