On Tue, Jul 21, 2020 at 11:54:49PM +0000, Tian, Kevin wrote: > In a nutshell, applications don't require raw WQ controllability as guest > kernel drivers may expect. Extending DSA user space interface to be another > passthrough interface just for virtualization needs is less compelling than > leveraging established VFIO/mdev framework (with the major merit that > existing user space VMMs just work w/o any change as long as they already > support VFIO uAPI). Sure, but the above is how the cover letter should have summarized that discussion, not as "it is not much code difference" > In last review you said that you didn't hard nak this approach and would > like to hear opinion from virtualization guys. In this version we CCed KVM > mailing list, Paolo (VFIO/Qemu), Alex (VFIO), Samuel (Rust-VMM/Cloud > hypervisor), etc. Let's see how they feel about this approach. Yes, the VFIO community should decide. If we are doing emulation tasks in the kernel now, then I can think of several nice semi-emulated mdevs to propose. This will not be some one off, but the start of a widely copied pattern. Jason
