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

[Knut Omang]

On Mon, 2014-10-20 at 20:18 +0200, Jan Kiszka wrote:
> On 2014-10-20 17:15, Knut Omang wrote:
> > On Mon, 2014-10-20 at 17:23 +0300, Michael S. Tsirkin wrote:
> >> WRT intel_iommu, it does not yet seem to be as fully functional as I
> >> hoped.  People also discussed the best way to handle virtio versus iommu
> >> (it bypasses it ATM).
> >> 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?
> > 
> > Note that you have to explicitly enable iommu support in the guest
> > (intel_iommu=on on the boot command line in the Linux case) for it to
> > have any effect apart from being visible in the DMAR table and logging
> > so it should not really do any harm.
> > 
> > From my perspective the feature works well and I have been running a few
> > virtual machines with div.network workload stable using the additional 4
> > patches referred to in this post (Jan's two for interrupt remapping and
> > two bug fixes and enhancements from me for running behind bridges) :
> > 
> > https://lists.nongnu.org/archive/html/qemu-devel/2014-08/msg02986.html
> > 
> > Latest version here:
> > 
> > https://github.com/knuto/qemu/tree/sriov_patches_v2
> > 
> > Give me a hint and I can rebase and post the two iommu patches, I
> > believe Jan wanted to do some more work on the interrupt remapping
> > first.
> 
> You should avoid to depend on my series regarding upstreaming of fixes
> or features that can be done independently. Did your bridging fixes
> depend on IR? Can you break them up?

Yes, that was my intention with the comment (to rebase to make my two
commits independent of your interrupt remapping commits) but I realize
the language in my comment was not clear - sorry for the confusion,..

Knut