On 30-Aug 19:24, Song Liu wrote:
>
>
> > On Aug 30, 2019, at 11:53 AM, Anton Protopopov <a.s.protopopov@xxxxxxxxx> wrote:
> >
> > чт, 29 авг. 2019 г. в 16:02, Song Liu <songliubraving@xxxxxx>:
> >>
> >>
> >>
> >>> On Aug 14, 2019, at 5:03 PM, Anton Protopopov <a.s.protopopov@xxxxxxxxx> wrote:
> >>>
> >>
> >> [...]
> >>
> >>>
> >>>
> >>> int bpf_object__unload(struct bpf_object *obj)
> >>> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> >>> index e8f70977d137..634f278578dd 100644
> >>> --- a/tools/lib/bpf/libbpf.h
> >>> +++ b/tools/lib/bpf/libbpf.h
> >>> @@ -63,8 +63,13 @@ LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
> >>> struct bpf_object;
> >>>
> >>> struct bpf_object_open_attr {
> >>> - const char *file;
> >>> + union {
> >>> + const char *file;
> >>> + const char *obj_name;
> >>> + };
> >>> enum bpf_prog_type prog_type;
> >>> + void *obj_buf;
> >>> + size_t obj_buf_sz;
> >>> };
> >>
> >> I think this would break dynamically linked libbpf. No?
> >
> > Ah, yes, sure. What is the right way to make changes which break ABI in libbpf?
>
> I don't have a good idea here on the top of my head.
>
> Maybe we need a new struct and/or function for this.
I incorporated the suggested fixes and sent a new patch for this as we
ran into pretty much the same issue. (i.e. not being able to set
needs_kver / flags).
https://lore.kernel.org/bpf/20190927130834.18829-1-kpsingh@xxxxxxxxxxxx/T/#u
- KP
>
> >
> > BTW, does the commit ddc7c3042614 ("libbpf: implement BPF CO-RE offset
> > relocation algorithm") which adds a new field to the struct
> > bpf_object_load_attr also break ABI?
>
> I think this change was in the same release, so it is OK.
>
> Thanks,
> Song
