From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH] virtio-net: init link state correctly Date: Wed, 3 Nov 2010 10:00:19 +0200 Message-ID: <20101103080019.GC6772@redhat.com> References: <20101103070817.26272.31654.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, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org To: Jason Wang Return-path: Content-Disposition: inline In-Reply-To: <20101103070817.26272.31654.stgit@dhcp-91-158.nay.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Nov 03, 2010 at 03:08:17PM +0800, Jason Wang wrote: > We need call netif_carrier_off() and do not assume VIRTIO_NET_S_LINKUP > before querying device state during probing, otherwise we may get > wrong operstate after driver was loaded because the link watch event > was not fired as expected. > > Since the device state changed could be caught through interrupt, the > unconditional call to nerif_carrier_on() is also removed. > > Signed-off-by: Jason Wang OK, but this seems broken for hosts without VIRTIO_NET_F_STATUS. Right? Probably /* 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)) { vi->status = 0; netif_carrier_off(dev); virtnet_update_status(vi); } else { vi->status = VIRTIO_NET_S_LINK_UP; netif_carrier_on(dev); } Makes sense? > --- > drivers/net/virtio_net.c | 3 +-- > 1 files changed, 1 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index bb6b67f..0a0cd35 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -986,9 +986,8 @@ static int virtnet_probe(struct virtio_device *vdev) > goto unregister; > } > > - vi->status = VIRTIO_NET_S_LINK_UP; > + netif_carrier_off(dev); > virtnet_update_status(vi); > - netif_carrier_on(dev); > > pr_debug("virtnet: registered device %s\n", dev->name); > return 0;