Re: [Qemu-devel] [PATCH v2 0/2] vfio: blacklist legacy virtio devices

[Jason Wang]

On 2016年08月30日 10:27, Michael S. Tsirkin wrote:
> Legacy virtio devices always bypassed an IOMMU, so using them with vfio was
> never safe.

And it actually won't work since GPA is assumed in the device. So I'm 
not sure this is must since we should get a IOMMU fault in this case.

>   This adds a quirk detecting these and disabling VFIO unless the
> noiommu mode is used.  At the moment, this only applies to virtio-pci devices.
>
> The patch might make sense on stable as well.
>
> Michael S. Tsirkin (2):
>    vfio: report group noiommu status
>    vfio: add virtio pci quirk
>
>   drivers/vfio/pci/vfio_pci_private.h |   1 +
>   include/linux/vfio.h                |   2 +
>   drivers/vfio/pci/vfio_pci.c         |  14 ++++
>   drivers/vfio/pci/vfio_pci_virtio.c  | 140 ++++++++++++++++++++++++++++++++++++
>   drivers/vfio/vfio.c                 |  12 ++++
>   drivers/vfio/pci/Makefile           |   1 +
>   6 files changed, 170 insertions(+)
>   create mode 100644 drivers/vfio/pci/vfio_pci_virtio.c