RE: [PATCH v2 06/19] iommufd/viommu: Add IOMMU_VIOMMU_SET/UNSET_VDEV_ID ioctl

[Tian, Kevin]

> From: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Sent: Friday, September 6, 2024 4:15 AM
> 
> On Thu, Sep 05, 2024 at 02:43:26PM -0300, Jason Gunthorpe wrote:
> > On Thu, Sep 05, 2024 at 10:37:45AM -0700, Nicolin Chen wrote:
> > > That being said, if we have a clear picture that in the long term
> > > we would extend it to hold more information, I think it could be
> > > a smart move.
> > >
> > > Perhaps virtual device can have its own "attach" to vIOMMU? Or
> > > would you still prefer attaching via proxy hwpt_nested?
> >
> > I was thinking just creating it against a vIOMMU is an effective
> > "attach" and the virtual device is permanently tied to the vIOMMU at
> > creation time.
> 
> Ah, right! The create is per-viommu, so it's being attached.
> 

presumably we also need check compatibility between the idev
which the virtual device is created against and the stage-2 pgtable,
as a normal attach required?