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Date: Fri, 7 Dec 2018 13:26:10 -0500
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [RFC 0/2] Attempt to implement the standby feature
 for assigned network devices
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To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>, Michael Roth <mdroth@linux.vnet.ibm.com>, Sameeh Jubran <sameeh@daynix.com>, Yan Vugenfirer <yan@daynix.com>, Jason Wang <jasowang@redhat.com>, qemu-devel@nongnu.org

On Fri, Dec 07, 2018 at 04:46:29PM +0000, Daniel P. Berrang=E9 wrote:
> I'm not convinced it is useful enough to justify playing games in qdev
> with dynamically hiding devices. This adds complexity to the code which
> will make it harder to maintain and debug at runtime.

I actually think a hidden device is a useful concept to model.
E.g. you can have a powered off slot and a PCI device in
such a slot isn't visible but isn't gone either.

Right now we force-eject such devices.

But it sounds reasonable that e.g. a bunch of guests cooperate
and share an assigned device and then whoever wants to
use it, powers it up. These patches do not implement this
of course but it's a step in that direction.

--=20
MST