> From: Xia, Chenbo <chenbo....@intel.com> > Sent: Tuesday, June 15, 2021 11:03 AM > > Hi Parav, > > > -----Original Message----- > > From: Parav Pandit <pa...@nvidia.com> > > Sent: Tuesday, June 15, 2021 12:05 PM > > To: Xia, Chenbo <chenbo....@intel.com>; NBU-Contact-Thomas Monjalon > > <tho...@monjalon.net>; Yigit, Ferruh <ferruh.yi...@intel.com> > > Cc: Xueming(Steven) Li <xuemi...@nvidia.com>; Slava Ovsiienko > > <viachesl...@nvidia.com>; dev@dpdk.org; Jason Gunthorpe > > <j...@nvidia.com> > > Subject: RE: [dpdk-dev] [RFC 00/14] mlx5: support SubFunction > > > > Hi Chenbo, > > > > > From: Xia, Chenbo <chenbo....@intel.com> > > > Sent: Tuesday, June 15, 2021 7:41 AM > > > > > > Hi Thomas, > > > > > > > From: Thomas Monjalon <tho...@monjalon.net> > > > > Sent: Friday, June 11, 2021 3:54 PM > > [..] > > > > > > > > Yes. In our term it's called Assignable Device Interface (ADI) > > > introduced in Intel Scalable IOV > > > (https://01.org/blogs/2019/assignable-interfaces-intel- > > > scalable-i/o-virtualization-linux) > > > > > > And vfio-mdev is chosen to be the software framework for it. I start > > > to > > realize > > > there is difference between SF and ADI: SF considers multi-function > > > devices which may include net/regex/vdpa/... > > Yes. net, rdma, vdpa, regex ++. > > And eventually vfio_device to map to VM too. > > > > Non mdev framework is chosen so that all the use cases of kernel only, > > or user only or mix modes can be supported. > > OK. Got it. > > > > > > But ADI only focuses on the > > > virtualization of the devices and splitting devices to logic parts > > > and > > providing > > > huge number of interfaces to host APP. I think SF also considers > > > this but is mainly used for multi-function devices (like DPU in your term? > > > Correct me if I'm wrong). > > > > > SF also supports DPU mode too but it is in addition to above use cases. > > SF will expose mdev (or a vfio_device) to map to a VM. > > So your SW actually supports vfio-mdev? I suppose the device-specific mdev > Kernel module is out-of-tree? > mlx5 driver doesn't support vfio_device for SFs. Kernel plumbing for PASID assignment to SF is WIP currently kernel community. We do not have any out-of-tree kernel module.
> Just FYI: > > We are introducing a new mdev bus for DPDK: > http://patchwork.dpdk.org/project/dpdk/cover/20210601030644.3318-1- > chenbo....@intel.com/ > I am yet to read about it. But I am not sure what value does it add. A user can open a vfio device using vfio subsystem and operate on it. A vfio device can be a create as a result of binding PCI VF/PF to vfio-pci driver or a SF by binding SF to vfio_foo driver. There is kernel work in progress to use vfio core as library. So we do not anticipate to use add mdev layer and uuid to create a vfio device for a SF. For Intel, ADI will never has any netdevs or rdma dev?
