# Re: \[PATCH v3 net-next 2/2\] bpf: let bpf\_warn\_invalid\_xdp\_action() report more info

- From: Paolo Abeni \<pabeni@redhat.com\>
- Date: 2021-12-06 10:20:19 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/12/7788105
- Thread: https://ratatoskr.run/netdev/2021/11/7787416/t.md

```text
On Fri, 2021-12-03 at 23:04 +0100, Daniel Borkmann wrote:
> Hi Paolo,
> 
> Changes look good to me as well, we can route the series via bpf-next after tree
> resync, or alternatively ask David/Jakub to take it directly into net-next with our
> Ack given in bpf-next there is no drivers/net/ethernet/microsoft/mana/mana_bpf.c yet.
> 
> On 11/30/21 11:08 AM, Paolo Abeni wrote:
> [...]> diff --git a/net/core/filter.c b/net/core/filter.c
> > index 5631acf3f10c..392838fa7652 100644
> > --- a/net/core/filter.c
> > +++ b/net/core/filter.c
> > @@ -8181,13 +8181,13 @@ static bool xdp_is_valid_access(int off, int size,
> >   	return __is_valid_xdp_access(off, size);
> >   }
> >   
> > -void bpf_warn_invalid_xdp_action(u32 act)
> > +void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
> >   {
> >   	const u32 act_max = XDP_REDIRECT;
> >   
> > -	pr_warn_once("%s XDP return value %u, expect packet loss!\n",
> > +	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
> >   		     act > act_max ? "Illegal" : "Driver unsupported",
> > -		     act);
> > +		     act, prog->aux->name, prog->aux->id, dev ? dev->name : "");
> 
> One tiny nit, but we could fix it up while applying I'd have is that for !dev case
> we should probably dump a "<n/a>" or so just to avoid a kernel log message like
> "dev , expect packet loss".

Yep, that would probably be better. Pleas let me know it you prefer a
formal new version for the patch.

Thanks!

Paolo


```