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From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PULL 18/33] vhost-user-scsi: Introduce
 vhost-user-scsi host device
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To: Felipe Franciosi <felipe@nutanix.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, QEMU Developers <qemu-devel@nongnu.org>, "Michael S. Tsirkin" <mst@redhat.com>

> > How, since there is no synchronization point between the vhost-user
> > server on the source and the destination?
> 
> The idea is that the backend should both stop picking up new requests and
> also quiesce outstanding requests upon a GET_VRING_BASE vhost message.

This could be documented, but perhaps it's best to add a START_STOP
feature and message to the vhost-user protocol?

The feature then can be optional for vhost-user-net and mandatory for
vhost-user-scsi.  When this is done we can remove .unmigratable.

Thanks,

Paolo

> > 
> > Can you please send a version of your patch that uses .unmigratable?
> 
> Sure I can do that. We can work on the migration later on.
> 
> > 
> > I'll send a v6 that momentarily drops vhost-scsi, but I intend to
> > include it again in the next pull request.
> 
> Sounds good to me.
> 
> Felipe
> 
> > 
> > Thanks,
> > 
> > Paolo
> 
>