Re: [PATCH v2 00/10] RFC: NVME MDEV

From: Keith Busch
Date: Thu May 09 2019 - 09:56:00 EST

On Thu, May 09, 2019 at 02:12:55AM -0700, Stefan Hajnoczi wrote:
> On Mon, May 06, 2019 at 12:04:06PM +0300, Maxim Levitsky wrote:
> > On top of that, it is expected that newer hardware will support the PASID based
> > device subdivision, which will allow us to _directly_ pass through the
> > submission queues of the device and _force_ us to use the NVME protocol for the
> > frontend.
> I don't understand the PASID argument. The data path will be 100%
> passthrough and this driver won't be necessary.

We still need a non-passthrough component to handle slow path,
non-doorbell controller registers and admin queue. That doesn't
necessarily need to be a kernel driver, though.