Re: [PATCH net-next 08/10] net: vxlan: add drop reasons support to vxlan_xmit_one()

[Menglong Dong]

On Tue, Aug 20, 2024 at 8:33 PM Ido Schimmel <idosch@xxxxxxxxxx> wrote:
>
> On Thu, Aug 15, 2024 at 08:43:00PM +0800, Menglong Dong wrote:
> > diff --git a/drivers/net/vxlan/drop.h b/drivers/net/vxlan/drop.h
> > index da30cb4a9ed9..542f391b1273 100644
> > --- a/drivers/net/vxlan/drop.h
> > +++ b/drivers/net/vxlan/drop.h
> > @@ -14,6 +14,7 @@
> >       R(VXLAN_DROP_MAC)                       \
> >       R(VXLAN_DROP_TXINFO)                    \
> >       R(VXLAN_DROP_REMOTE)                    \
> > +     R(VXLAN_DROP_REMOTE_IP)                 \
> >       /* deliberate comment for trailing \ */
> >
> >  enum vxlan_drop_reason {
> > diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
> > index 22e2bf532ac3..c1bae120727f 100644
> > --- a/drivers/net/vxlan/vxlan_core.c
> > +++ b/drivers/net/vxlan/vxlan_core.c
> > @@ -2375,6 +2375,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
> >       bool xnet = !net_eq(vxlan->net, dev_net(vxlan->dev));
> >       bool no_eth_encap;
> >       __be32 vni = 0;
> > +     SKB_DR(reason);
> >
> >       no_eth_encap = flags & VXLAN_F_GPE && skb->protocol != htons(ETH_P_TEB);
> >       if (!skb_vlan_inet_prepare(skb, no_eth_encap))
> > @@ -2396,6 +2397,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
> >                                                  default_vni, true);
> >                               return;
> >                       }
> > +                     reason = (u32)VXLAN_DROP_REMOTE_IP;
>
> This looks quite obscure to me. I didn't know you can add 0.0.0.0 as
> remote and I'm not sure what is the use case. Personally I wouldn't
> bother with this reason.
>

I know. I'm hesitant about this commit, as I don't find a case
for this dropping, and the remote seems can't be 0.0.0.0.
I add this reason as the code drops the packet here.

Enn...I will abandon this commit.

Thanks!
Menglong Dong

> >                       goto drop;
> >               }