From: Dimitris Michailidis <dmich...@google.com> Date: Mon, 16 May 2016 15:33:35 -0700
> The goal of netdev_add_tso_features() is to enable all TSO features but > it unintentionally loses NETIF_F_ALL_FOR_ALL features. This is because > the netdev_increment_features() it calls clears any NETIF_F_ALL_FOR_ALL > bits that aren't included in the incremental features and none of them > are included in NETIF_F_ALL_TSO. The behavior can be seen by enabling > tx-nocache-copy on the slaves and noticing the feature remains off at > the master. > > Fix this by including NETIF_F_ALL_FOR_ALL in the incremental features. > > Signed-off-by: Dave Platt <dpl...@google.com> > Signed-off-by: Dimitris Michailidis <dmich...@google.com> This doesn't look right to me at all. The second argument to netdev_increment_features, 'one', clearly states that all it is supposed to do is handle a new device being added which has the features mentioned in 'one'. It makes no sense to arbitrarily add ALL_FOR_ALL in there, and if it is legitimate, why doesn't every other call site of netdev_increment_features have this same problem? If netdev_increment_features is doing something different either it's documentation is wrong or it's implementation is losing ALL_FOR_ALL bits erroneously.
