From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] bridge: remove a redundant synchronize_net()
Date: Thu, 04 Apr 2013 09:03:45 -0700
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Cc: David Miller <davem@davemloft.net>, vfalico@redhat.com,
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On Thu, 2013-04-04 at 08:44 -0700, Eric Dumazet wrote:

> Because maybe the synchronize_net() in netdev_rx_handler_unregister()
> is enough and you dont even need the call_rcu(). Thats was my question.

So we have the following sequence in team_port_del()

        netdev_rx_handler_unregister(port_dev);

        netdev_upper_dev_unlink(port_dev, dev);
        team_port_disable_netpoll(port);
        vlan_vids_del_by_dev(port_dev, dev);
        dev_uc_unsync(port_dev, dev);
        dev_mc_unsync(port_dev, dev);
        dev_close(port_dev);
        team_port_leave(team, port);

        __team_option_inst_mark_removed_port(team, port);
        __team_options_change_check(team);
        __team_option_inst_del_port(team, port);
        __team_port_change_port_removed(port);

        team_port_set_orig_dev_addr(port);
        dev_set_mtu(port_dev, port->orig.mtu);
        synchronize_rcu();
        kfree(port);

And I suspect we can remove synchronize_rcu() call.

But as this is a long list of operations, maybe some of them requires
the rcu grace period before kfree(port)