On Sat, 2011-04-02 at 04:54 +0100, David Miller wrote: > From: MichaÅ MirosÅaw <mirq-linux@xxxxxxxxxxxx> > Date: Thu, 31 Mar 2011 13:01:35 +0200 (CEST) > > > Not tested in any way. The original code for offload setting seems broken > > as it resets the features on every netback reconnect. > > > > This will set GSO_ROBUST at device creation time (earlier than connect time). > > > > RX checksum offload is forced on - so advertise as it is. > > > > Signed-off-by: MichaÅ MirosÅaw <mirq-linux@xxxxxxxxxxxx> > > Applied. Thanks, but unfortunately the patch results in the features all being disabled by default, since they are not set in the initial dev->features and the initial dev->wanted_features is based on features & hw_features. The ndo_fix_features hook only clears features and doesn't add new features (nor should it AFAICT). Features cannot be negotiated with the backend until xennet_connect(). The carrier is not enabled until the end of that function, therefore I think it is safe to start with a full set of features in dev->features and rely on the call to netdev_update_features() in xennet_connect() to clear those which turn out to be unavailable. The following works for me, I guess the alternative is for xennet_connect() to expand dev->features based on what it detects? Or is there a mechanism for a driver to inform the core that a new hardware feature has become available (I doubt that really happens on physical h/w so I guess not). Ian. 8<----------------- >From 0b56469abe56efae415b4603ef508ce9aec0e4c1 Mon Sep 17 00:00:00 2001 From: Ian Campbell <ian.campbell@xxxxxxxxxx> Date: Mon, 4 Apr 2011 10:58:50 +0100 Subject: [PATCH] xen: netfront: assume all hw features are available until backend connection setup We need to assume that all features will be available when registering the netdev otherwise they are ommitted from the initial set of dev->wanted_features. When we connect to the backed we reduce the set as necessary due to the call to netdev_update_features() in xennet_connect(). Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx> Cc: mirq-linux@xxxxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx <netdev@xxxxxxxxxxxxxxx> Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx> Cc: konrad.wilk@xxxxxxxxxx Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx> Cc: xen-devel@xxxxxxxxxxxxxxxxxxx --- drivers/net/xen-netfront.c | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 0cfe4cc..db9a763 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1251,6 +1251,14 @@ static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev NETIF_F_GSO_ROBUST; netdev->hw_features = NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_TSO; + /* + * Assume that all hw features are available for now. This set + * will be adjusted by the call to netdev_update_features() in + * xennet_connect() which is the earliest point where we can + * negotiate with the backend regarding supported features. + */ + netdev->features |= netdev->hw_features; + SET_ETHTOOL_OPS(netdev, &xennet_ethtool_ops); SET_NETDEV_DEV(netdev, &dev->dev); -- 1.7.2.5 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
