From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [V2 PATCH] virtio-net: init link state correctly Date: Fri, 5 Nov 2010 10:45:33 +0200 Message-ID: <20101105084533.GB3464@redhat.com> References: <20101105025008.3277.87697.stgit@dhcp-91-158.nay.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: rusty@rustcorp.com.au, davem@davemloft.net, markmc@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org To: Jason Wang Return-path: Content-Disposition: inline In-Reply-To: <20101105025008.3277.87697.stgit@dhcp-91-158.nay.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Fri, Nov 05, 2010 at 10:50:08AM +0800, Jason Wang wrote: > For device that supports VIRTIO_NET_F_STATUS, there's no need to > assume the link is up and we need to call nerif_carrier_off() before > querying device status, otherwise we may get wrong operstate after > diver was loaded because the link watch event was not fired as > expected. > > For device that does not support VIRITO_NET_F_STATUS, we could not get > its status through virtnet_update_status() and what we can only do is > always assuming the link is up. > > Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin > --- > drivers/net/virtio_net.c | 12 +++++++++--- > 1 files changed, 9 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index bb6b67f..b6d4028 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -986,9 +986,15 @@ static int virtnet_probe(struct virtio_device *vdev) > goto unregister; > } > > - vi->status = VIRTIO_NET_S_LINK_UP; > - virtnet_update_status(vi); > - netif_carrier_on(dev); > + /* Assume link up if device can't report link status, > + otherwise get link status from config. */ > + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) { > + netif_carrier_off(dev); > + virtnet_update_status(vi); > + } else { > + vi->status = VIRTIO_NET_S_LINK_UP; > + netif_carrier_on(dev); > + } > > pr_debug("virtnet: registered device %s\n", dev->name); > return 0;