From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:35162)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mst@redhat.com>) id 1bcO9V-0002qf-Lc
	for qemu-devel@nongnu.org; Tue, 23 Aug 2016 22:42:54 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <mst@redhat.com>) id 1bcO9P-0003SG-OK
	for qemu-devel@nongnu.org; Tue, 23 Aug 2016 22:42:52 -0400
Received: from mx1.redhat.com ([209.132.183.28]:38854)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mst@redhat.com>) id 1bcO9P-0003S4-IJ
	for qemu-devel@nongnu.org; Tue, 23 Aug 2016 22:42:47 -0400
Date: Wed, 24 Aug 2016 05:42:44 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20160824054226-mutt-send-email-mst@kernel.org>
References: <1471613966-7267-1-git-send-email-rkagan@virtuozzo.com>
	<1471613966-7267-2-git-send-email-rkagan@virtuozzo.com>
	<20160823210332.GA6227@stefanha-x1.localdomain>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20160823210332.GA6227@stefanha-x1.localdomain>
Subject: Re: [Qemu-devel] [PATCH v2 1/6] virtio: assert on ->inuse underflow
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel/>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>, qemu-devel@nongnu.org, "Denis V. Lunev" <den@openvz.org>, Ladi Prosek <lprosek@redhat.com>

On Tue, Aug 23, 2016 at 05:03:32PM -0400, Stefan Hajnoczi wrote:
> On Fri, Aug 19, 2016 at 04:39:20PM +0300, Roman Kagan wrote:
> > Make sure that ->inuse counter on virtqueue never goes negative.
> > 
> > This complements commit afd9096eb1882f23929f5b5c177898ed231bac66,
> > "virtio: error out if guest exceeds virtqueue size", which, due to
> > signed ->inuse comparison against unsigned ->vring.num, manifested a bug
> > in virtio-balloon where virtqueue_push() was called before the matching
> > virtqueu_pop(). [That problem will be addressed in followup patches].
> > 
> > Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
> > Cc: "Michael S. Tsirkin" <mst@redhat.com>
> > Cc: Ladi Prosek <lprosek@redhat.com>
> > Cc: Stefan Hajnoczi <stefanha@redhat.com>
> > ---
> >  hw/virtio/virtio.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

I'm not merging any asserts before 2.7. Please resubmit when 2.7
is out.