On Fri, Jun 18, 2021 at 4:13 PM jjedwa165 <jonathan.edwards@xxxxxxxxxxxxxxxxxxxxx> wrote: > > eBPF has been backported for RHEL 7 w/ kernel 3.10-940+ [0]. However > only the following program types are supported [1] > > BPF_PROG_TYPE_KPROBE > BPF_PROG_TYPE_TRACEPOINT > BPF_PROG_TYPE_PERF_EVENT > > For libbpf this causes an EINVAL return during the bpf_object__probe_loading > call which only checks to see if programs of type BPF_PROG_TYPE_SOCKET_FILTER > can load. > > The following will try BPF_PROG_TYPE_TRACEPOINT as a fallback attempt before > erroring out. BPF_PROG_TYPE_KPROBE was not a good candidate because on some > kernels it requires knowledge of the LINUX_VERSION_CODE. > > [0] https://www.redhat.com/en/blog/introduction-ebpf-red-hat-enterprise-linux-7 > [1] https://access.redhat.com/articles/3550581 > > Signed-off-by: jjedwa165 <jonathan.edwards@xxxxxxxxxxxxxxxxxxxxx> > --- LGTM, but please re-submit with your real first and last name in Signed-off-by. Also add my ack: Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx> > tools/lib/bpf/libbpf.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index 48c0ade05..1e04ce724 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -4000,6 +4000,10 @@ bpf_object__probe_loading(struct bpf_object *obj) > attr.license = "GPL"; > > ret = bpf_load_program_xattr(&attr, NULL, 0); > + if (ret < 0) { > + attr.prog_type = BPF_PROG_TYPE_TRACEPOINT; > + ret = bpf_load_program_xattr(&attr, NULL, 0); > + } > if (ret < 0) { > ret = errno; > cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); > -- > 2.17.1 >
