Re: [PATCH v2 bpf-next 2/4] bpf: handle bpf_user_pt_regs_t typedef explicitly for PTR_TO_CTX global arg

[Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx>]

On Tue, Feb 13, 2024 at 10:48 AM Eduard Zingerman <eddyz87@xxxxxxxxx> wrote:
>
> On Tue, 2024-02-13 at 10:12 -0800, Andrii Nakryiko wrote:
> [...]
>
> > Yeah, and then special case, for KPROBE that `struct
> > bpf_user_pt_regs_t` (not a typedef!) is also acceptable.
>
> Hm, I missed the point that for kporbes there is a need to accept both
> simultaneously (for the same running kernel):
>
>     typedef __whatever__ bpf_user_pt_regs_t;
>     struct bpf_user_pt_regs_t {};
>
> If this is the only such case, then I agree that special case is
> simplest to implement.

Yeah, it's backwards compatibility quirk which is important to preserve