From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [patch net-next V2] net: introduce ethernet teaming device
Date: Sun, 23 Oct 2011 16:37:48 +0200
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To: Jiri Pirko <jpirko@redhat.com>
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Le dimanche 23 octobre 2011 =C3=A0 14:51 +0200, Jiri Pirko a =C3=A9crit=
 :

> Yes. And team->mode_ops.receive can change only after synchronize_rcu=
 is
> done. It's not possible it changes within the window you are talking =
about.

If it was true, you would not need the synchronize_rcu() call you added
in __team_change_mode() :


----------------------------------------------------------------------

static int __team_change_mode(struct team *team,
                             const struct team_mode *new_mode)
{
       /* Check if mode was previously set and do cleanup if so */
       if (team->mode_kind) {
               void (*exit_op)(struct team *team) =3D team->mode_ops.ex=
it;

               /* Clear ops area so no callback is called any longer */
               team_mode_ops_clear(&team->mode_ops);

               synchronize_rcu();

               if (exit_op)
                       exit_op(team);


-----------------------------------------------------------------------

So the question is : Why do you have this synchronize_rcu() call here ?