Zhu, Lingshan
2023-Sep-22 03:45 UTC
[PATCH vfio 11/11] vfio/virtio: Introduce a vfio driver over virtio devices
On 9/22/2023 2:39 AM, Jason Gunthorpe wrote:> On Thu, Sep 21, 2023 at 12:53:04PM -0400, Michael S. Tsirkin wrote: >>> vdpa is not vfio, I don't know how you can suggest vdpa is a >>> replacement for a vfio driver. They are completely different >>> things. >>> Each side has its own strengths, and vfio especially is accelerating >>> in its capability in way that vpda is not. eg if an iommufd conversion >>> had been done by now for vdpa I might be more sympathetic. >> Yea, I agree iommufd is a big problem with vdpa right now. Cindy was >> sick and I didn't know and kept assuming she's working on this. I don't >> think it's a huge amount of work though. I'll take a look. >> Is there anything else though? Do tell. > Confidential compute will never work with VDPA's approach.I don't understand why vDPA can not and will never support Confidential computing? Do you see any blockers?> >> There are a bunch of things that I think are important for virtio >> that are completely out of scope for vfio, such as migrating >> cross-vendor. > VFIO supports migration, if you want to have cross-vendor migration > then make a standard that describes the VFIO migration data format for > virtio devices. > >> What is the huge amount of work am I asking to do? > You are asking us to invest in the complexity of VDPA through out > (keep it working, keep it secure, invest time in deploying and > debugging in the field) > > When it doesn't provide *ANY* value to the solution. > > The starting point is a completely working vfio PCI function and the > end goal is to put that function into a VM. That is VFIO, not VDPA. > > VPDA is fine for what it does, but it is not a reasonable replacement > for VFIO. > > Jason