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From:   Chuhong Yuan <hslester96@gmail.com>
Date:   Thu, 1 Aug 2019 10:22:07 +0800
Message-ID: <CANhBUQ1J8hXBZv4x3pJhG_08ZS1zR=9Uj2EUta2sgtyND_QKPw@mail.gmail.com>
Subject: Re: [PATCH 2/2] cnic: Use refcount_t for refcount
To:     Michael Chan <michael.chan@broadcom.com>
Cc:     "David S . Miller" <davem@davemloft.net>,
        Netdev <netdev@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
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Michael Chan <michael.chan@broadcom.com> =E4=BA=8E2019=E5=B9=B48=E6=9C=881=
=E6=97=A5=E5=91=A8=E5=9B=9B =E4=B8=8A=E5=8D=881:58=E5=86=99=E9=81=93=EF=BC=
=9A
>
> On Wed, Jul 31, 2019 at 5:22 AM Chuhong Yuan <hslester96@gmail.com> wrote=
:
>
> >  static void cnic_ctx_wr(struct cnic_dev *dev, u32 cid_addr, u32 off, u=
32 val)
> > @@ -494,7 +494,7 @@ int cnic_register_driver(int ulp_type, struct cnic_=
ulp_ops *ulp_ops)
> >         }
> >         read_unlock(&cnic_dev_lock);
> >
> > -       atomic_set(&ulp_ops->ref_count, 0);
> > +       refcount_set(&ulp_ops->ref_count, 0);
> >         rcu_assign_pointer(cnic_ulp_tbl[ulp_type], ulp_ops);
> >         mutex_unlock(&cnic_lock);
> >
>
> Willem's comment applies here too.  The driver needs to be modified to
> count from 1 to use refcount_t.
>
> Thanks.

I have revised this problem but find the other two refcounts -
cnic_dev::ref_count
and cnic_sock::ref_count have no set.
I am not sure where to initialize them to 1.

Besides, should ulp_ops->ref_count be set to 0 when unregistered?