Re: [PATCH v2 bpf-next 05/20] bpf: Introduce bpf_arena.

[Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>]

On Fri, Feb 9, 2024 at 12:36 PM David Vernet <void@xxxxxxxxxxxxx> wrote:
> > +     if (attr->map_extra & ~PAGE_MASK)
> > +             /* If non-zero the map_extra is an expected user VMA start address */
> > +             return ERR_PTR(-EINVAL);
>
> So I haven't done a thorough review of this patch, beyond trying to
> understand the semantics of bpf arenas. On that note, could you please
> document the semantics of map_extra with arena maps where map_extra is
> defined in [0]?
>
> [0]: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/tree/include/uapi/linux/bpf.h#n1439

Good point. Done.