From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60823) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bCuUv-0005rj-LQ for qemu-devel@nongnu.org; Tue, 14 Jun 2016 15:59:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bCuUu-0001QB-QC for qemu-devel@nongnu.org; Tue, 14 Jun 2016 15:59:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55394) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bCuUu-0001Q0-K7 for qemu-devel@nongnu.org; Tue, 14 Jun 2016 15:59:40 -0400 Date: Tue, 14 Jun 2016 22:59:39 +0300 From: "Michael S. Tsirkin" Message-ID: <20160614225939-mutt-send-email-mst@redhat.com> References: <1465934227-16558-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1465934227-16558-1-git-send-email-mst@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL v2 04/32] tests/vhost-user-bridge: workaround stale vring base List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Yuanhan Liu , Victor Kaplansky From: Marc-Andr=E9 Lureau This patch is a similar solution to what Yuanhan Liu/Huawei Xie have suggested for DPDK. When vubr quits (killed or crashed), a restart of vubr would get stale vring base from QEMU. That would break the kernel virtio net completely, making it non-work any more, unless a driver reset is done. So, instead of getting the stale vring base from QEMU, Huawei suggested we could get a proper one from used->idx. This works because the queues packets are processed in order. Signed-off-by: Marc-Andr=E9 Lureau Tested-by: Yuanhan Liu Reviewed-by: Yuanhan Liu Reviewed-by: Victor Kaplansky Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- tests/vhost-user-bridge.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tests/vhost-user-bridge.c b/tests/vhost-user-bridge.c index e231ce9..36b3cd8 100644 --- a/tests/vhost-user-bridge.c +++ b/tests/vhost-user-bridge.c @@ -946,6 +946,13 @@ vubr_set_vring_addr_exec(VubrDev *dev, VhostUserMsg = *vmsg) DPRINT(" vring_avail at %p\n", vq->avail); =20 vq->last_used_index =3D vq->used->idx; + + if (vq->last_avail_index !=3D vq->used->idx) { + DPRINT("Last avail index !=3D used index: %d !=3D %d, resuming", + vq->last_avail_index, vq->used->idx); + vq->last_avail_index =3D vq->used->idx; + } + return 0; } =20 --=20 MST