Re: [Qemu-devel] [PATCH] intel_iommu: fix VTD_SID_TO_BUS

[Michael S. Tsirkin]

On Mon, Oct 20, 2014 at 04:37:15PM +0200, Jan Kiszka wrote:
> On 2014-10-20 16:23, Michael S. Tsirkin wrote:
> > 
> > WRT intel_iommu, it does not yet seem to be as fully functional as I
> > hoped.
> 
> What is missing or broken?

PCI to PCI bridges don't work, do they?

> >  People also discussed the best way to handle virtio versus iommu
> > (it bypasses it ATM).
> 
> We need to declare in the ACPI tables that the emulated IOMMUs do not
> cover those "special" virtio devices.

I'd also be fine if we flat out disallow adding virtio
devices to such systems for now, or anything else that
does not work.
Patches for either approach aren't yet available, are they?

> > I'd like to suggest we hide the iommu from the command line
> > help for 2.2, this way people don't activate it mistakenly.
> > 
> > Let's make it more complete and then enable for 2.3.
> > 
> > Thoughts?
> 
> We need the list of issues on the table, then we can decide.
> 
> Jan
> 
> -- 
> Siemens AG, Corporate Technology, CT RTC ITP SES-DE
> Corporate Competence Center Embedded Linux