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Date: Thu, 1 Feb 2018 19:08:15 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [RFC 0/2] virtio-vhost-user: add virtio-vhost-user
 device
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To: Wei Wang <wei.w.wang@intel.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>, qemu-devel@nongnu.org, zhiyong.yang@intel.com, Maxime Coquelin <maxime.coquelin@redhat.com>, jasowang@redhat.com

On Tue, Jan 30, 2018 at 08:09:19PM +0800, Wei Wang wrote:
> Issues:
> Suppose we have both the vhost and virtio-net set up, and vhost pmd <->
> virtio-net pmd communication works well. Now, vhost pmd exits (virtio-net
> pmd is still there). Some time later, we re-run vhost pmd, the vhost pmd
> doesn't know the virtqueue addresses of the virtio-net pmd, unless the
> virtio-net pmd reloads to start the 2nd phase of the vhost-user protocol. So
> the second run of the vhost pmd won't work.
> 
> Any thoughts?
> 
> Best,
> Wei

So vhost in qemu must resend all configuration on reconnect.
Does this address the issues?

-- 
MST