Hi Parav,

-----Original Message-----
From: Parav Pandit <redacted>
Sent: Tuesday, June 15, 2021 12:05 PM
To: Xia, Chenbo <redacted>; NBU-Contact-Thomas Monjalon
[off-list ref]; Yigit, Ferruh [off-list ref]
Cc: Xueming(Steven) Li <redacted>; Slava Ovsiienko
[off-list ref]; dev@dpdk.org; Jason Gunthorpe [off-list ref]
Subject: RE: [dpdk-dev] [RFC 00/14] mlx5: support SubFunction

Hi Chenbo,

quoted

From: Xia, Chenbo <redacted>
Sent: Tuesday, June 15, 2021 7:41 AM

Hi Thomas,

quoted

From: Thomas Monjalon <redacted>
Sent: Friday, June 11, 2021 3:54 PM

[..]

quoted

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

quoted

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.

quoted

But ADI only focuses on the
virtualization of the devices and splitting devices to logic parts and

providing

quoted

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?

Just FYI:

We are introducing a new mdev bus for DPDK:
http://patchwork.dpdk.org/project/dpdk/cover/20210601030644.3318-1-chenbo.xia@intel.com/

Thanks,
Chenbo

quoted

And I also noticed that the mdev-based interface can only be used in
userspace but aux-based interface can also be used by other kernel sub-
system (like for net, wrap it as netdev).

Correct.