# Re: \[Patch bpf-next v3 3/5\] bpf: compute data\_end dynamically with JIT code

- From: Jakub Sitnicki \<jakub@cloudflare.com\>
- Date: 2021-02-15 19:07:14 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/02/7760457
- Thread: https://ratatoskr.run/netdev/2021/02/7760432/t.md

```text
On Sat, Feb 13, 2021 at 10:44 PM CET, Cong Wang wrote:
> From: Cong Wang <redacted>
>
> Currently, we compute ->data_end with a compile-time constant
> offset of skb. But as Jakub pointed out, we can actually compute
> it in eBPF JIT code at run-time, so that we can competely get
> rid of ->data_end. This is similar to skb_shinfo(skb) computation
> in bpf_convert_shinfo_access().
>
> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
> Cc: John Fastabend <john.fastabend@gmail.com>
> Cc: Daniel Borkmann <daniel@iogearbox.net>
> Cc: Lorenz Bauer <redacted>
> Signed-off-by: Cong Wang <redacted>
> ---

Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
```