On Thu, Jul 30, 2020 at 2:02 PM Song Liu <songliubraving@xxxxxx> wrote:
>
>
>
> > On Jul 29, 2020, at 4:05 PM, Andrii Nakryiko <andriin@xxxxxx> wrote:
> >
> > Add ability to force-detach BPF link. Also add missing error message, if
> > specified link ID is wrong.
> >
> > Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
>
> Acked-by: Song Liu <songliubraving@xxxxxx>
>
> With two nitpicks below.
>
> [...]
>
> > static int link_parse_fd(int *argc, char ***argv)
> > {
> > + int fd;
> > +
> > if (is_prefix(**argv, "id")) {
> > unsigned int id;
> > char *endptr;
> > @@ -35,7 +37,10 @@ static int link_parse_fd(int *argc, char ***argv)
> > }
> > NEXT_ARGP();
> >
> > - return bpf_link_get_fd_by_id(id);
> > + fd = bpf_link_get_fd_by_id(id);
> > + if (fd < 0)
> > + p_err("failed to get link with ID %d: %d", id, -errno);
>
> How about we print strerror(errno) to match the rest of link.c?
sure, will do, was lazy :)
>
> [...]
>
> > +static int do_detach(int argc, char **argv)
> > +{
> > + int err, fd;
> > +
> > + if (argc != 2)
> > + return BAD_ARG();
> > +
> > + fd = link_parse_fd(&argc, &argv);
> > + if (fd < 0)
> > + return 1;
> > +
> > + err = bpf_link_detach(fd);
> > + if (err)
> > + err = -errno;
> > + close(fd);
> > + if (err) {
> > + p_err("failed link detach: %d", err);
>
> And strerror(err) here.
>
>
