From: Maxim Mikityanskiy maximmi@mellanox.com
[ Upstream commit f01204ec8be7ea5e8f0230a7d4200e338d563bde ]
The legacy ethtool userspace tool shows an error when no features could be changed. It's useful to have a netlink reply to be able to show this error when __netdev_update_features wasn't called, for example:
1. ethtool -k eth0 large-receive-offload: off 2. ethtool -K eth0 rx-fcs on 3. ethtool -K eth0 lro on Could not change any device features rx-lro: off [requested on] 4. ethtool -K eth0 lro on # The output should be the same, but without this patch the kernel # doesn't send the reply, and ethtool is unable to detect the error.
This commit makes ethtool-netlink always return a reply when requested, and it still avoids unnecessary calls to __netdev_update_features if the wanted features haven't changed.
Fixes: 0980bfcd6954 ("ethtool: set netdev features with FEATURES_SET request") Signed-off-by: Maxim Mikityanskiy maximmi@mellanox.com Reviewed-by: Michal Kubecek mkubecek@suse.cz Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ethtool/features.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
--- a/net/ethtool/features.c +++ b/net/ethtool/features.c @@ -268,14 +268,11 @@ int ethnl_set_features(struct sk_buff *s bitmap_and(req_wanted, req_wanted, req_mask, NETDEV_FEATURE_COUNT); bitmap_andnot(new_wanted, old_wanted, req_mask, NETDEV_FEATURE_COUNT); bitmap_or(req_wanted, new_wanted, req_wanted, NETDEV_FEATURE_COUNT); - if (bitmap_equal(req_wanted, old_wanted, NETDEV_FEATURE_COUNT)) { - ret = 0; - goto out_rtnl; + if (!bitmap_equal(req_wanted, old_wanted, NETDEV_FEATURE_COUNT)) { + dev->wanted_features &= ~dev->hw_features; + dev->wanted_features |= ethnl_bitmap_to_features(req_wanted) & dev->hw_features; + __netdev_update_features(dev); } - - dev->wanted_features &= ~dev->hw_features; - dev->wanted_features |= ethnl_bitmap_to_features(req_wanted) & dev->hw_features; - __netdev_update_features(dev); ethnl_features_to_bitmap(new_active, dev->features); mod = !bitmap_equal(old_active, new_active, NETDEV_FEATURE_COUNT);