On 01/05/21 08:44, Alexei Starovoitov wrote: > > Any pointer to an example test I could base this on? > > selftests/bpf/ I was hoping for something more elaborate. I thought there's something already there that do some verification for raw tracepoint that I could either extend or replicate. Otherwise this could end up being a time sink for me and I'm not keen on jumping down this rabbit hole. > > > - add a doc with contents from commit log. > > > > You're referring to the ABI part of the changelog, right? > > > > > The "Does bpf make things into an abi ?" question keeps coming back > > > over and over again. > > > Everytime we have the same answer that No, bpf cannot bake things into abi. > > > I think once it's spelled out somewhere in Documentation/ it would be easier to > > > repeat this message. > > > > How about a new Documentation/bpf/ABI.rst? I can write something up initially > > for us to discuss in detail when I post. > > There is Documentation/bpf/bpf_design_QA.rst > and we already have this text in there that was added back in 2017: > > 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 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. > > I'm suggesting to add an additional section to this Q/A doc to include > more or less > the same text you had in the commit log. Works for me. Thanks -- Qais Yousef
