From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56416) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhhB6-0002o0-GM for qemu-devel@nongnu.org; Wed, 07 Sep 2016 14:02:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bhhB5-0003VV-H5 for qemu-devel@nongnu.org; Wed, 07 Sep 2016 14:02:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43770) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhhB5-0003VQ-BL for qemu-devel@nongnu.org; Wed, 07 Sep 2016 14:02:27 -0400 Date: Wed, 7 Sep 2016 14:02:20 -0400 From: Stefan Hajnoczi Message-ID: <20160907180220.GD18576@stefanha-x1.localdomain> References: <1473261649-31465-1-git-send-email-lprosek@redhat.com> <1473261649-31465-4-git-send-email-lprosek@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="IMjqdzrDRly81ofr" Content-Disposition: inline In-Reply-To: <1473261649-31465-4-git-send-email-lprosek@redhat.com> Subject: Re: [Qemu-devel] [PATCH 3/3] virtio-balloon: fix stats vq migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Ladi Prosek Cc: qemu-devel@nongnu.org, mst@redhat.com, rkagan@virtuozzo.com --IMjqdzrDRly81ofr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 07, 2016 at 05:20:49PM +0200, Ladi Prosek wrote: > The statistics virtqueue is not migrated properly because virtio-balloon > does not include s->stats_vq_elem in the migration stream. >=20 > After migration the statistics virtqueue hangs because the host never > completes the last element (s->stats_vq_elem is NULL on the destination > QEMU). Therefore the guest never submits new elements and the virtqueue > is hung. >=20 > Instead of changing the migration stream format in an incompatible way, > detect the migration case and rewind the virtqueue so the last element > can be completed. >=20 > Cc: Michael S. Tsirkin > Cc: Roman Kagan > Cc: Stefan Hajnoczi > Suggested-by: Roman Kagan > Signed-off-by: Ladi Prosek > --- > hw/virtio/virtio-balloon.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) Reviewed-by: Stefan Hajnoczi --IMjqdzrDRly81ofr Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJX0FYsAAoJEJykq7OBq3PImK8H/2Hawm5ho+WRvI6rVL++k150 ifzZsSXiRF4iYVCEOwWqBMDN54ASisSPwfTXH6RgOX1UBpyw+YBHDkk5vf1IdE3K 2QCfn/bHNJdbP/v/le/4YkNUkOoSOPxAC13GF3I5rbkpTgGTk9vtCqX1jFOc0+e3 OUjTigll1rZGtoMhqzS2fnxkDcwUibNRoDBdbCc1s59nIHpnvA6iQr2WA+WZ92rR m5/0gk4h4C796dC2QdgAUCc9nBPGow006373wLiEaZHbxoL7+zEIKF93icjJqqGy 9YPKMZuWRTjV7rHVYmiVEiNQl8E3f/XiyVJmYh1WGWUVsSr4n3y0BSJpkpJXUkU= =ViFD -----END PGP SIGNATURE----- --IMjqdzrDRly81ofr--