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Date: Tue, 06 Mar 2012 15:59:53 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 2/3] virtio-balloon: note optional features
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: amit.shah@redhat.com, uobergfe@redhat.com, owasserm@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com

Il 06/03/2012 15:55, Michael S. Tsirkin ha scritto:
> > It is not a problem if the destination does not have
> > VIRTIO_BALLOON_F_MUST_TELL_HOST.  In that case, the guest
> > will simply do useless virtqueue traffic, but the destination
> > does not have a problem.
> > (In fact, it _is_ a problem if the destination has
> > VIRTIO_BALLOON_F_MUST_TELL_HOST but the source does not.
> > The feature bit should have been backwards!  Luckily,
> > our implementation is free from this problem).
> > 
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> 
> Can't we just add a flag to control this feature?

I think the sane thing here would be to remove it from the spec.

Paolo