On Tue, Aug 18, 2020 at 07:05:16PM +0200, Paolo Bonzini wrote: > On 18/08/20 18:49, Jason Gunthorpe wrote: > > On Tue, Aug 18, 2020 at 06:27:21PM +0200, Paolo Bonzini wrote: > >> On 18/08/20 13:50, Jason Gunthorpe wrote: > >>> For instance, what about suspend/resume of containers using idxd? > >>> Wouldn't you want to have the same basic approach of controlling the > >>> wq from userspace that virtualization uses? > >> > >> The difference is that VFIO more or less standardizes the approach you > >> use for live migration. With another interface you'd have to come up > >> with something for every driver, and add support in CRIU for every > >> driver as well. > > > > VFIO is very unsuitable for use as some general userspace. It only 1:1 > > with a single process and just can't absorb what the existing idxd > > userspace is doing. > > The point of mdev is that it's not 1:1 anymore. The lifecycle model of mdev is not compatible with how something like idxd works, it needs a multi-open cdev. Jason
