[RESEND PATCH] virtio-net: init link state correctly

[RESEND PATCH] virtio-net: init link state correctly

[Jason Wang]

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.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 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;

Re: [RESEND PATCH] virtio-net: init link state correctly

[Rusty Russell]

On Fri, 5 Nov 2010 08:17:18 pm 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.
> 
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Acked-by: Rusty Russell <rusty@rustcorp.com.au>

Thanks!
Rusty.

Re: [RESEND PATCH] virtio-net: init link state correctly

[Michael S. Tsirkin]

On Mon, Nov 08, 2010 at 09:41:27AM +1030, Rusty Russell wrote:
> On Fri, 5 Nov 2010 08:17:18 pm 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.
> > 
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > Signed-off-by: Jason Wang <jasowang@redhat.com>
> 
> Acked-by: Rusty Russell <rusty@rustcorp.com.au>
> 
> Thanks!
> Rusty.

Rusty, just to verify: who shall be queueing this up?

Re: [RESEND PATCH] virtio-net: init link state correctly

[Rusty Russell]

On Thu, 11 Nov 2010 01:38:23 am Michael S. Tsirkin wrote:
> On Mon, Nov 08, 2010 at 09:41:27AM +1030, Rusty Russell wrote:
> > On Fri, 5 Nov 2010 08:17:18 pm 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.
> > > 
> > > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > 
> > Acked-by: Rusty Russell <rusty@rustcorp.com.au>
> > 
> > Thanks!
> > Rusty.
> 
> Rusty, just to verify: who shall be queueing this up?

Sorry, that was sloppy of me; was meant for DaveM to take.

Sending explicitly now...
Rusty.