Re: Should I add BPF kfuncs for userspace apps? And how?

Hi Akihiko,

On Tue, Dec 12, 2023 at 12:05 AM Akihiko Odaki akihiko.odaki@daynix.com wrote:

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I'm working on a new feature that aids virtio-net implementations using tuntap virtual network device. You can see [1] for details, but basically it's to extend BPF_PROG_TYPE_SOCKET_FILTER to report four more bytes.

AFAICT, [1] adds a new program type, which is really hard to ship. However, you mentioned it is basically "extend BPF_PROG_TYPE_SOCKET_FILTER to report four more bytes", which confuses me.

Can we achieve the same goal by extending BPF_PROG_TYPE_SOCKET_FILTER (without adding a new program type)? Does this require extending __sk_buff, which is also not an option any more?

Thanks, Song