Re: [Qemu-devel] [RFC v2 0/8] VIRTIO-IOMMU device

[Bharat Bhushan]

Hi Eric,

> -----Original Message-----
> From: Auger Eric [mailto:address@hidden
> Sent: Friday, June 09, 2017 12:14 PM
> To: Bharat Bhushan <address@hidden>;
> address@hidden; address@hidden;
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> address@hidden; address@hidden
> Cc: address@hidden; address@hidden; address@hidden;
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> Subject: Re: [RFC v2 0/8] VIRTIO-IOMMU device
> 
> Hi Bharat,
> 
> On 09/06/2017 08:16, Bharat Bhushan wrote:
> > Hi Eric,
> >
> >> -----Original Message-----
> >> From: Eric Auger [mailto:address@hidden
> >> Sent: Wednesday, June 07, 2017 9:31 PM
> >> To: address@hidden; address@hidden;
> >> address@hidden; address@hidden;
> address@hidden;
> >> address@hidden; address@hidden; jean-
> >> address@hidden
> >> Cc: address@hidden; address@hidden;
> address@hidden;
> >> address@hidden; address@hidden;
> >> address@hidden; address@hidden; address@hidden; Bharat
> Bhushan
> >> <address@hidden>
> >> Subject: [RFC v2 0/8] VIRTIO-IOMMU device
> >>
> >> This series implements the virtio-iommu device. This is a proof of
> >> concept based on the virtio-iommu specification written by Jean-Philippe
> Brucker [1].
> >> This was tested with a guest using the virtio-iommu driver [2] and
> >> exposed with a virtio-net-pci using dma ops.
> >>
> >> The device gets instantiated using the "-device virtio-iommu-device"
> >> option. It currently works with ARM virt machine only as the machine
> >> must handle the dt binding between the virtio-mmio "iommu" node and
> >> the PCI host bridge node. ACPI booting is not yet supported.
> >>
> >> This should allow to start some benchmarking activities against pure
> >> emulated IOMMU (especially ARM SMMU).
> >
> > I am testing this on ARM64 and see below continuous error prints:
> >
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >     virtio_iommu_translate sid=8 is not known!!
> >
> >
> > Also in guest I do not see device-tree node with virtio-iommu.
> do you mean the virtio-mmio with #iommu-cells property?
> 
> This one is created statically by virt machine. I would be surprised if it 
> were
> not there. Are you using the virt = virt2.10 machine. Machines before do not
> support its instantiation.
> 
> Please can you add a printf in hw/arm/virt.c create_virtio_mmio() at the
> moment when this node is created. Also you can add a printf in
> bind_virtio_iommu_device() to make sure the binding with the PCI host
> bridge is added on machine init done.
> 
> Also worth to check, CONFIG_VIRTIO_IOMMU=y on guest side.

It works on my side. The driver config was disabled and also I was using guest 
kernel which was not have deferred-probing. Now after fixing it works on my side
I placed some prints to see dma-map are mapping regions in virtio-iommu, it 
uses emulated iommu.

I will continue to add VFIO support now on this and more testing !!

Thanks
-Bharat

> 
> Thanks
> 
> Eric
> 
> > I am using qemu-tree you mentioned below and iommu-driver patches
> published by Jean-P.
> > Qemu command line have additional ""-device virtio-iommu-device". What
> I am missing ?
> 
> 
> >
> > Thanks
> > -Bharat
> >
> >>
> >> Best Regards
> >>
> >> Eric
> >>
> >> This series can be found at:
> >> https://github.com/eauger/qemu/tree/virtio-iommu-rfcv2
> >>
> >> References:
> >> [1] [RFC 0/3] virtio-iommu: a paravirtualized IOMMU, [2] [RFC PATCH
> >> linux]
> >> iommu: Add virtio-iommu driver [3] [RFC PATCH kvmtool 00/15] Add
> >> virtio- iommu
> >>
> >> History:
> >> v1 -> v2:
> >> - fix redifinition of viommu_as typedef
> >>
> >> Eric Auger (8):
> >>   update-linux-headers: import virtio_iommu.h
> >>   linux-headers: Update for virtio-iommu
> >>   virtio_iommu: add skeleton
> >>   virtio-iommu: Decode the command payload
> >>   virtio_iommu: Add the iommu regions
> >>   virtio-iommu: Implement the translation and commands
> >>   hw/arm/virt: Add 2.10 machine type
> >>   hw/arm/virt: Add virtio-iommu the virt board
> >>
> >>  hw/arm/virt.c                                 | 116 ++++-
> >>  hw/virtio/Makefile.objs                       |   1 +
> >>  hw/virtio/trace-events                        |  14 +
> >>  hw/virtio/virtio-iommu.c                      | 623
> ++++++++++++++++++++++++++
> >>  include/hw/arm/virt.h                         |   5 +
> >>  include/hw/virtio/virtio-iommu.h              |  60 +++
> >>  include/standard-headers/linux/virtio_ids.h   |   1 +
> >>  include/standard-headers/linux/virtio_iommu.h | 142 ++++++
> >>  linux-headers/linux/virtio_iommu.h            |   1 +
> >>  scripts/update-linux-headers.sh               |   3 +
> >>  10 files changed, 957 insertions(+), 9 deletions(-)  create mode
> >> 100644 hw/virtio/virtio-iommu.c  create mode 100644
> >> include/hw/virtio/virtio- iommu.h  create mode 100644
> >> include/standard- headers/linux/virtio_iommu.h  create mode 100644
> >> linux-headers/linux/virtio_iommu.h
> >>
> >> --
> >> 2.5.5
> >