Re: 3.6.11 AMD-Vi: Completion-Wait loop timed out

Jörg Rödel
2013-01-22T15:16:38Z

On Tue, Jan 22, 2013 at 09:36:34AM -0500, Boris Ostrovsky wrote:
>
>
> On 01/22/2013 09:13 AM, Udo van den Heuvel wrote:
> >Gigabyte demonstrate that using ESX 5i IOMMU works fine. (with pictures
> >attached).
>
> There are no attachments to your message.
>
> I am not sure that 5i supports IOMMU (but I may well be wrong).

Virtualization use-cases don't change the page-tables for the IOMMU very
often. So there is less need to flush the IO-TLB and IOMMU command
processing is utilized only from time to time.

In Linux however the page-tables change all the time and there is a much
higher load on the IOMMU command buffer which makes it much more likely
to trigger the hardware problem.

Joerg