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Subject: Re: [PATCH V2 3/5] vDPA: introduce vDPA bus
Thread-Topic: [PATCH V2 3/5] vDPA: introduce vDPA bus
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On Mon, Feb 17, 2020 at 02:08:03PM +0800, Jason Wang wrote:

> I thought you were copied in the patch [1], maybe we can move vhost relat=
ed
> discussion there to avoid confusion.
>
> [1] https://lwn.net/Articles/811210/

Wow, that is .. confusing.

So this is supposed to duplicate the uAPI of vhost-user? But it is
open coded and duplicated because .. vdpa?

> So it's cheaper and simpler to introduce a new bus instead of refactoring=
 a
> well known bus and API where brunches of drivers and devices had been
> implemented for years.

If you reason for this approach is to ease the implementation then you
should talk about it in the cover letters/etc

Maybe it is reasonable to do this because the rework is too great, I
don't know, but to me this whole thing looks rather messy.=20

Remember this stuff is all uAPI as it shows up in sysfs, so you can
easilly get stuck with it forever.

Jason