Re: [RFC v2 00/22] intel_iommu: expose Shared Virtual Addressing to VM

[Jason Wang]

On 2019/10/25 下午6:12, Tian, Kevin wrote:
> > From: Jason Wang [mailto:address@hidden]
> > Sent: Friday, October 25, 2019 5:49 PM
> >
> >
> > On 2019/10/24 下午8:34, Liu Yi L wrote:
> > > Shared virtual address (SVA), a.k.a, Shared virtual memory (SVM) on Intel
> > > platforms allow address space sharing between device DMA and
> > applications.
> >
> >
> > Interesting, so the below figure demonstrates the case of VM. I wonder
> > how much differences if we compare it with doing SVM between device
> > and
> > an ordinary process (e.g dpdk)?
> >
> > Thanks
> One difference is that ordinary process requires only stage-1 translation,
> while VM requires nested translation.


A silly question, then I believe there's no need for VFIO DMA API in 
this case consider the page table is shared between MMU and IOMMU?

Thanks

>