From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michal Kubecek <mkubecek@suse.cz>
Subject: Re: [PATCH net-next] net/core: ensure features get disabled on new
 lower devs
Date: Tue, 3 Nov 2015 22:53:10 +0100
Message-ID: <20151103215310.GA7839@unicorn.suse.cz>
References: <1446519359-21400-1-git-send-email-jarod@redhat.com>
 <1446583017-19021-1-git-send-email-jarod@redhat.com>
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Cc: linux-kernel@vger.kernel.org,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jay Vosburgh <j.vosburgh@gmail.com>,
	Veaceslav Falico <vfalico@gmail.com>,
	Andy Gospodarek <gospo@cumulusnetworks.com>,
	Jiri Pirko <jiri@resnulli.us>,
	Nikolay Aleksandrov <razor@blackwall.org>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	netdev@vger.kernel.org
To: Jarod Wilson <jarod@redhat.com>
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On Tue, Nov 03, 2015 at 03:36:57PM -0500, Jarod Wilson wrote:
> With moving netdev_sync_lower_features() after the .ndo_set_features
> calls, I neglected to verify that devices added *after* a flag had been
> disabled on an upper device were properly added with that flag disabled as
> well. This currently happens, because we exit __netdev_update_features()
> when we see dev->features == features for the upper dev. We can retain the
> optimization of leaving without calling .ndo_set_features with a bit of
> tweaking and a goto here.

I haven't reviewed the patch yet (I'm going to take a look with fresher
mind in the morning) but if you are going to handle this in a generic
way, you may want to remove the LRO specific hacks added to
bond_enslave() and team_port_add() by commit fbe168ba91f7 ("net: generic
dev_disable_lro() stacked device handling").

                                                          Michal Kubecek