diff options
author | Jonathan Edwards <jonathan.edwards@165gc.onmicrosoft.com> | 2021-06-19 11:10:07 -0400 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2021-06-21 17:21:07 +0200 |
commit | 5c10a3dbe9220ca7bcee716c13c8a8563bcb010a (patch) | |
tree | 55801dbb8639b57a73528e17ca35f7a2eac24c70 /tools/lib | |
parent | f42cfb469f9b4a1c002a03cce3d9329376800a6f (diff) |
libbpf: Add extra BPF_PROG_TYPE check to bpf_object__probe_loading
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: Jonathan Edwards <jonathan.edwards@165gc.onmicrosoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210619151007.GA6963@165gc.onmicrosoft.com
Diffstat (limited to 'tools/lib')
-rw-r--r-- | tools/lib/bpf/libbpf.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 48c0ade05ab1..1e04ce724240 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4001,6 +4001,10 @@ bpf_object__probe_loading(struct bpf_object *obj) 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)); pr_warn("Error in %s():%s(%d). Couldn't load trivial BPF " |