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From:   Long Li <longli@microsoft.com>
To:     Stephen Hemminger <stephen@networkplumber.org>,
        "longli@linuxonhyperv.com" <longli@linuxonhyperv.com>
CC:     KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>
Subject: RE: [PATCH] hv_netvsc: Mark VF as slave before exposing it to
 user-mode
Thread-Topic: [PATCH] hv_netvsc: Mark VF as slave before exposing it to
 user-mode
Thread-Index: AQHaB5W4U0Kx/aurvkOjV7lIJbHFdbBcSWCAgABHzdA=
Date:   Thu, 26 Oct 2023 21:07:22 +0000
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References: <1698274250-653-1-git-send-email-longli@linuxonhyperv.com>
 <20231026094841.39f01d26@hermes.local>
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> Subject: Re: [PATCH] hv_netvsc: Mark VF as slave before exposing it to us=
er-mode
>=20
> On Wed, 25 Oct 2023 15:50:50 -0700
> longli@linuxonhyperv.com wrote:
>=20
> > @@ -2347,6 +2342,12 @@ static int netvsc_register_vf(struct net_device
> *vf_netdev)
> >  	if (!ndev)
> >  		return NOTIFY_DONE;
> >
> > +	if (event =3D=3D NETDEV_POST_INIT) {
> > +		/* set slave flag before open to prevent IPv6 addrconf */
> > +		vf_netdev->flags |=3D IFF_SLAVE;
> > +		return NOTIFY_DONE;
> > +	}
> > +
> >  	net_device_ctx =3D netdev_priv(ndev);
> >  	netvsc_dev =3D rtnl_dereference(net_device_ctx->nvdev);
> >  	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
> > @@ -2753,8 +2754,9 @@ static int netvsc_netdev_event(struct notifier_bl=
ock
> *this,
> >  		return NOTIFY_DONE;
> >
> >  	switch (event) {
> > +	case NETDEV_POST_INIT:
> >  	case NETDEV_REGISTER:
> > -		return netvsc_register_vf(event_dev);
> > +		return netvsc_register_vf(event_dev, event);
>=20
> Although correct, this is an awkward way to write this.
> There are two events which call register_vf() but the post init one short=
 circuits
> and doesn't really register the VF.
>=20
> The code is clearer if flag is set in switch statement.
>=20

I will add a dedicated function to handle NETDEV_POST_INIT.

Thanks,
Long