virtio-net: init link state correctly
diff mbox series

Message ID 20101103070817.26272.31654.stgit@dhcp-91-158.nay.redhat.com
State New, archived
Headers show
Series
  • virtio-net: init link state correctly
Related show

Commit Message

Jason Wang Nov. 3, 2010, 7:08 a.m. UTC
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 <jasowang@redhat.com>
---
 drivers/net/virtio_net.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Comments

Michael S. Tsirkin Nov. 3, 2010, 8 a.m. UTC | #1
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 <jasowang@redhat.com>

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;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Patch
diff mbox series

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;