Re: [Qemu-devel] [V13 3/4] hw/i386: Introduce AMD IOMMU

[Alex Williamson <alex.williamson@redhat.com>]

On Fri,  8 Jul 2016 11:18:22 +0300
David Kiarie <davidkiarie4@gmail.com> wrote:

> Add AMD IOMMU emulaton to Qemu in addition to Intel IOMMU.
> The IOMMU does basic translation, error checking and has a
> minimal IOTLB implementation. This IOMMU bypassed the need
> for target aborts by responding with IOMMU_NONE access rights
> and exempts the region 0xfee00000-0xfeefffff from translation
> as it is the q35 interrupt region.
> 
> We advertise features that are not yet implemented to please
> the Linux IOMMU driver.
> 
> IOTLB aims at implementing commands on real IOMMUs which is
> essential for debugging and may not offer any performance
> benefits
> 
> Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
> ---
>  hw/i386/Makefile.objs |    1 +
>  hw/i386/amd_iommu.c   | 1384 +++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/i386/amd_iommu.h   |  285 ++++++++++
>  3 files changed, 1670 insertions(+)
>  create mode 100644 hw/i386/amd_iommu.c
>  create mode 100644 hw/i386/amd_iommu.h

Hi,

Please consider an update or follow-on patch which adds something
similar to:

commit 3cb3b1549f5401dc3a5e1d073e34063dc274136f
Author: Alex Williamson <alex.williamson@redhat.com>
Date:   Thu Jun 30 13:00:24 2016 -0600

    intel_iommu: Throw hw_error on notify_started

http://git.qemu.org/?p=qemu.git;a=commit;h=3cb3b1549f5401dc3a5e1d073e34063dc274136f

This would simply make amd_iommu incompatible with device assignment
until someone tackles adding the proper code to support it.  Thanks,

Alex