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Date:   Tue, 21 Jan 2020 09:15:14 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jason Gunthorpe <jgg@mellanox.com>
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Subject: Re: [PATCH 3/5] vDPA: introduce vDPA bus
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On Tue, Jan 21, 2020 at 02:12:05PM +0000, Jason Gunthorpe wrote:
> On Mon, Jan 20, 2020 at 04:56:06PM -0500, Michael S. Tsirkin wrote:
> > > For vfio? vfio is the only thing I am aware doing
> > > that, and this is not vfio..
> > 
> > vfio is not doing anything. anyone can use a combination
> > of unbind and driver_override to attach a driver to a device.
> > 
> > It's not a great interface but it's there without any code,
> > and it will stay there without maintainance overhead
> > if we later add a nicer one.
> 
> Well, it is not a great interface, and it is only really used in
> normal cases by vfio.
> 
> I don't think it is a good idea to design new subsystems with that
> idea in mind, particularly since detatching the vdpa driver would not
> trigger destruction of the underlying dynamic resource (ie the SF).
> 
> We need a way to trigger that destruction..
> 
> Jason 

You wanted a netlink command for this, right?

-- 
MST