Re: [PATCH v2 bpf-next 4/6] libbpf: don't enforce verifier log levels on libbpf side

Lorenz Bauer
2023-03-30T17:13:11Z

On Wed, Mar 29, 2023 at 12:56 AM Andrii Nakryiko <andrii@kernel.org> wrote:
>
> This basically prevents any forward compatibility. And we either way
> just return -EINVAL, which would otherwise be returned from bpf()
> syscall anyways.

In your cover letter you make the argument that applications can opt
out of the behaviour, but I think shows that this isn't entirely true.
Apps linking old libbpf won't be able to fix their breakage without
updating libbpf. This is especially annoying when you have to support
multiple old versions where doing this isn't straightforward.

Take this as another plea to make this opt in and instead work
together to make this a default on the lib side. :)