Re: [PATCH net-next] net/packet: Improve the comment about LL header visibility criteria

From: Willem de Bruijn
Date: Fri Feb 05 2021 - 23:07:36 EST


On Fri, Feb 5, 2021 at 5:42 PM Xie He <xie.he.0141@xxxxxxxxx> wrote:
>
> The "dev_has_header" function, recently added in
> commit d549699048b4 ("net/packet: fix packet receive on L3 devices
> without visible hard header"),
> is more accurate as criteria for determining whether a device exposes
> the LL header to upper layers, because in addition to dev->header_ops,
> it also checks for dev->header_ops->create.
>
> When transmitting an skb on a device, dev_hard_header can be called to
> generate an LL header. dev_hard_header will only generate a header if
> dev->header_ops->create is present.
>
> Signed-off-by: Xie He <xie.he.0141@xxxxxxxxx>

Acked-by: Willem de Bruijn <willemb@xxxxxxxxxx>

Indeed, existence of dev->header_ops->create is the deciding factor. Thanks Xie.