On Wed, Nov 20, 2019 at 11:03:57PM -0400, Jason Gunthorpe wrote: > Frankly, when I look at what this virtio stuff is doing I see RDMA: > - Both have a secure BAR pages for mmaping to userspace (or VM) > - Both are prevented from interacting with the device at a register > level and must call to the kernel - ie creating resources is a > kernel call - for security. > - Both create command request/response rings in userspace controlled > memory and have HW DMA to read requests and DMA to generate responses > - Both allow the work on the rings to DMA outside the ring to > addresses controlled by userspace. > - Both have to support a mixture of HW that uses on-device security > or IOMMU based security. The main difference is userspace/drivers need to be portable with virtio. -- MST
