RE: [PATCH v16 00/10] VIRTIO-IOMMU device

[Tian, Kevin]

> From: Jean-Philippe Brucker <address@hidden>
> Sent: Thursday, March 5, 2020 12:47 AM
>
[...]
> > >
> > > * We can't use DVM in nested mode unless the VMID is shared with the
> > > CPU. For that we'll need the host SMMU driver to hook into the KVM
> VMID
> > > allocator, just like we do for the ASID allocator. I haven't yet
> > > investigated how to do that. It's possible to do vSVA without DVM
> > > though, by sending all TLB invalidations through the SMMU command
> queue.
> > > "
> 
> Hm we're already mandating DVM for host SVA, so I'd say mandate it for
> vSVA as well. We'd avoid a ton of context switches, especially for the zip
> accelerator which doesn't require ATC invalidations. The host needs to pin
> the VMID allocated by KVM and write it in the endpoint's STE.
> 

Curious... what is DVM and how is it related to SVA? Is it SMMU specific?