diff options
| author | Alexei Starovoitov <ast@kernel.org> | 2019-01-07 15:52:00 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2019-01-07 15:52:00 -0800 |
| commit | 2dc0f02da14e19f510694f8d8bbcb0f2f63e0646 (patch) | |
| tree | c285c4764bb1c33787412c575c1f5dacf693ffea | |
| parent | a8911d6d5878587767a78c6bde371298ca2a3be3 (diff) | |
| parent | 80f21ff987eb377140d27102285f8dd1167b335c (diff) | |
Merge branch 'bpf-doc-updates'
Daniel Borkmann says:
====================
Two trivial doc follow-ups to i) remove deprecated kern_version
mentioning in the design qa and ii) to mention stand-alone build
and license of libbpf. Thanks!
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | Documentation/bpf/bpf_design_QA.rst | 11 | ||||
| -rw-r--r-- | tools/lib/bpf/README.rst | 14 |
2 files changed, 19 insertions, 6 deletions
diff --git a/Documentation/bpf/bpf_design_QA.rst b/Documentation/bpf/bpf_design_QA.rst index 6780a6d81745..7cc9e368c1e9 100644 --- a/Documentation/bpf/bpf_design_QA.rst +++ b/Documentation/bpf/bpf_design_QA.rst @@ -157,12 +157,11 @@ Q: Does BPF have a stable ABI? ------------------------------ A: YES. BPF instructions, arguments to BPF programs, set of helper functions and their arguments, recognized return codes are all part -of ABI. However when tracing programs are using bpf_probe_read() helper -to walk kernel internal datastructures and compile with kernel -internal headers these accesses can and will break with newer -kernels. The union bpf_attr -> kern_version is checked at load time -to prevent accidentally loading kprobe-based bpf programs written -for a different kernel. Networking programs don't do kern_version check. +of ABI. However there is one specific exception to tracing programs +which are using helpers like bpf_probe_read() to walk kernel internal +data structures and compile with kernel internal headers. Both of these +kernel internals are subject to change and can break with newer kernels +such that the program needs to be adapted accordingly. Q: How much stack space a BPF program uses? ------------------------------------------- diff --git a/tools/lib/bpf/README.rst b/tools/lib/bpf/README.rst index 056f38310722..607aae40f4ed 100644 --- a/tools/lib/bpf/README.rst +++ b/tools/lib/bpf/README.rst @@ -132,6 +132,20 @@ For example, if current state of ``libbpf.map`` is: Format of version script and ways to handle ABI changes, including incompatible ones, described in details in [1]. +Stand-alone build +================= + +Under https://github.com/libbpf/libbpf there is a (semi-)automated +mirror of the mainline's version of libbpf for a stand-alone build. + +However, all changes to libbpf's code base must be upstreamed through +the mainline kernel tree. + +License +======= + +libbpf is dual-licensed under LGPL 2.1 and BSD 2-Clause. + Links ===== |