From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Tan, Jianfeng" Subject: Re: [PATCH] vhost: call rte_vhost_enable_guest_notification only on enabled queues Date: Thu, 7 Apr 2016 19:48:36 +0800 Message-ID: <57064914.4040703@intel.com> References: <1459988946-5956-1-git-send-email-rich.lane@bigswitch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Tetsuya Mukawa , Yuanhan Liu To: Rich Lane , dev@dpdk.org Return-path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id B9B722949 for ; Thu, 7 Apr 2016 13:48:38 +0200 (CEST) In-Reply-To: <1459988946-5956-1-git-send-email-rich.lane@bigswitch.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi, On 4/7/2016 8:29 AM, Rich Lane wrote: > If the vhost PMD were configured with more queues than the guest, the old > code would segfault in rte_vhost_enable_guest_notification due to a NULL > virtqueue pointer. > > Fixes: ee584e9710b9 ("vhost: add driver on top of the library") > Signed-off-by: Rich Lane > --- > drivers/net/vhost/rte_eth_vhost.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c > index b1eb082..310cbef 100644 > --- a/drivers/net/vhost/rte_eth_vhost.c > +++ b/drivers/net/vhost/rte_eth_vhost.c > @@ -265,7 +265,6 @@ new_device(struct virtio_net *dev) > vq->device = dev; > vq->internal = internal; > vq->port = eth_dev->data->port_id; > - rte_vhost_enable_guest_notification(dev, vq->virtqueue_id, 0); > } > for (i = 0; i < eth_dev->data->nb_tx_queues; i++) { > vq = eth_dev->data->tx_queues[i]; > @@ -274,9 +273,11 @@ new_device(struct virtio_net *dev) > vq->device = dev; > vq->internal = internal; > vq->port = eth_dev->data->port_id; > - rte_vhost_enable_guest_notification(dev, vq->virtqueue_id, 0); > } > > + for (i = 0; i < dev->virt_qp_nb * VIRTIO_QNUM; i++) > + rte_vhost_enable_guest_notification(dev, i, 0); > + > dev->flags |= VIRTIO_DEV_RUNNING; > dev->priv = eth_dev; > eth_dev->data->dev_link.link_status = ETH_LINK_UP; Just one question, when qemu starts a vm, usually, only one queue is enabled, then only 1 tx and 1 rx are called rte_vhost_enable_guest_notification; but after system is up, we use "ethtool -K eth0 combined x" to enable multiqueues, there's no chance to call rte_vhost_enable_guest_notification for other queues, right? Thanks, Jianfeng