8.04 server + ubuntu-xen-server dies under disk load on AMD Opteron

[James Troup]

"Sam Howard" <sam.howard at gmail.com> writes:

>   PCI-DMA: OUT OF SW-IOMMU space for 65535 bytes at address xxxx
>   <some other stuff>
>   [ 1839.394603] ata2.00 status: {DRDY}
>
> It's hard to get all of the messages before it reboots.
>
> Fails with the same errors on both x64 and i386.
>
> Any ideas?  This makes for a pretty non-functional Xen server.  :(

Try adding 'swiotlb=64' to your kernel command line arguments.  The
SW-IOMMU size default/detection has regressed in hardy.

-- 
James