RE: [PATCH] selftests/bpf: Fix return value check in attach_bpf()

[John Fastabend]

John Fastabend wrote:
> Yu Kuai wrote:
> > use libbpf_get_error() to check the return value of
> > bpf_program__attach().
> > 
> > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> > Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> > ---
> >  tools/testing/selftests/bpf/benchs/bench_rename.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/tools/testing/selftests/bpf/benchs/bench_rename.c b/tools/testing/selftests/bpf/benchs/bench_rename.c
> > index c7ec114eca56..b7d4a1d74fca 100644
> > --- a/tools/testing/selftests/bpf/benchs/bench_rename.c
> > +++ b/tools/testing/selftests/bpf/benchs/bench_rename.c
> > @@ -65,7 +65,7 @@ static void attach_bpf(struct bpf_program *prog)
> >  	struct bpf_link *link;
> >  
> >  	link = bpf_program__attach(prog);
> > -	if (!link) {
> > +	if (libbpf_get_error(link)) {
> >  		fprintf(stderr, "failed to attach program!\n");
> >  		exit(1);
> >  	}
> > -- 
> 
> Probably should be IS_ERR(link) same as the other benchs/*.c progs.

Oops on wrong branch, agree with Daniel looks fine as !link otherwise
need an explanation and fix the rest of the cases.