From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id E34897D4A for ; Mon, 4 Dec 2017 15:09:42 +0100 (CET) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2E477780D0; Mon, 4 Dec 2017 14:09:42 +0000 (UTC) Received: from localhost.localdomain (ovpn-112-49.ams2.redhat.com [10.36.112.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1FCB15C54A; Mon, 4 Dec 2017 14:09:33 +0000 (UTC) From: Maxime Coquelin To: dev@dpdk.org, yliu@fridaylinux.org, tiwei.bie@intel.com, jianfeng.tan@intel.com Cc: lprosek@redhat.com, lersek@redhat.com, Maxime Coquelin Date: Mon, 4 Dec 2017 15:09:00 +0100 Message-Id: <20171204140900.7906-5-maxime.coquelin@redhat.com> In-Reply-To: <20171204140900.7906-1-maxime.coquelin@redhat.com> References: <20171204140900.7906-1-maxime.coquelin@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 04 Dec 2017 14:09:42 +0000 (UTC) Subject: [dpdk-dev] [PATCH 4/4] vhost: destroy unused virtqueues when multiqueue not negotiated X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 04 Dec 2017 14:09:43 -0000 QEMU sends VHOST_USER_SET_VRING_CALL requests for all queues declared in QEMU command line before the guest is started. It has the effect in DPDK vhost-user backend to allocate vrings for all queues declared by QEMU. If the first driver being used does not support multiqueue, the device never changes to VIRTIO_DEV_RUNNING state as only the first queue pair is initialized. One driver impacted by this bug is virtio-net's iPXE driver which does not support VIRTIO_NET_F_MQ feature. It is safe to destroy unused virtqueues in SET_FEATURES request handler, as it is ensured the device is not in running state at this stage, so virtqueues aren't being processed. Signed-off-by: Maxime Coquelin --- lib/librte_vhost/vhost_user.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index 7d84af3e2..72526e006 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -173,6 +173,7 @@ vhost_user_get_features(struct virtio_net *dev) static int vhost_user_set_features(struct virtio_net *dev, uint64_t features) { + int i; uint64_t vhost_features = 0; rte_vhost_driver_get_features(dev->ifname, &vhost_features); @@ -216,6 +217,24 @@ vhost_user_set_features(struct virtio_net *dev, uint64_t features) (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? "on" : "off", (dev->features & (1ULL << VIRTIO_F_VERSION_1)) ? "on" : "off"); + if (!(dev->features & (1ULL << VIRTIO_NET_F_MQ))) { + /* + * Remove all but first queue pair if MQ hasn't been + * negotiated. This is safe because the device is not + * running at this stage. + */ + for (i = dev->nr_vring; i > 1; i--) { + struct vhost_virtqueue *vq = dev->virtqueue[i]; + + if (!vq) + continue; + + cleanup_vq(vq, 1); + free_vq(vq); + dev->nr_vring--; + } + } + return 0; } -- 2.14.3