On Mon, Mar 28, 2022 at 8:23 PM Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > > On Mon, Mar 28, 2022 at 09:53:27AM +0800, Jason Wang wrote: > > To me, it looks more easier to not answer this question by letting > > userspace know about the change, > > That is not backwards compatbile, so I don't think it helps unless we > say if you open /dev/vfio/vfio you get old behavior and if you open > /dev/iommu you get new... Actually, this is one way to go. Trying to behave exactly like typ1 might be not easy. > > Nor does it answer if I can fix RDMA or not :\ > vDPA has a backend feature negotiation, then actually, userspace can tell vDPA to go with the new accounting approach. Not sure RDMA can do the same. Thanks > So we really do need to know what exactly is the situation here. > > Jason >
