From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH net v2] virtio_net: fix virtnet_open and virtnet_probe competing for try_fill_recv Date: Thu, 26 May 2016 12:36:18 +0300 Message-ID: <20160526123420-mutt-send-email-mst@redhat.com> References: <5746976F.60306@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, jasowang@redhat.com, rusty@rustcorp.com.au, netdev@vger.kernel.org, liuyongan@huawei.com To: wangyunjian Return-path: Received: from mx1.redhat.com ([209.132.183.28]:38267 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750791AbcEZJgW (ORCPT ); Thu, 26 May 2016 05:36:22 -0400 Content-Disposition: inline In-Reply-To: <5746976F.60306@huawei.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, May 26, 2016 at 02:27:59PM +0800, wangyunjian wrote: > In function virtnet_open() and virtnet_probe(), func try_fill_recv() > will be executed at the same time. VQ in virtqueue_add() is not protected > well and BUG_ON will be triggered when virito_net.ko being removed. > > Signed-off-by: Yunjian Wang Acked-by: Michael S. Tsirkin > --- > drivers/net/virtio_net.c | 18 ++---------------- > 1 file changed, 2 insertions(+), 16 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 49d84e5..e0638e5 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1925,24 +1925,11 @@ static int virtnet_probe(struct virtio_device *vdev) > > virtio_device_ready(vdev); > > - /* Last of all, set up some receive buffers. */ > - for (i = 0; i < vi->curr_queue_pairs; i++) { > - try_fill_recv(vi, &vi->rq[i], GFP_KERNEL); > - > - /* If we didn't even get one input buffer, we're useless. */ > - if (vi->rq[i].vq->num_free == > - virtqueue_get_vring_size(vi->rq[i].vq)) { > - free_unused_bufs(vi); > - err = -ENOMEM; > - goto free_recv_bufs; > - } > - } > - > vi->nb.notifier_call = &virtnet_cpu_callback; > err = register_hotcpu_notifier(&vi->nb); > if (err) { > pr_debug("virtio_net: registering cpu notifier failed\n"); > - goto free_recv_bufs; > + goto free_unregister_netdev; > } > > /* Assume link up if device can't report link status, > @@ -1960,10 +1947,9 @@ static int virtnet_probe(struct virtio_device *vdev) > > return 0; > > -free_recv_bufs: > +free_unregister_netdev: > vi->vdev->config->reset(vdev); > > - free_receive_bufs(vi); > unregister_netdev(dev); > free_vqs: > cancel_delayed_work_sync(&vi->refill); > -- > 1.7.12.4 >