On Fri, Oct 1, 2021 at 4:06 AM Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote: > > 2021-09-30 13:17 UTC+0100 ~ Quentin Monnet <quentin@xxxxxxxxxxxxx> > > 2021-09-30 12:33 UTC+0100 ~ Quentin Monnet <quentin@xxxxxxxxxxxxx> > >> API headers from libbpf should not be accessed directly from the > >> library's source directory. Instead, they should be exported with "make > >> install_headers". Let's make sure that bpf/preload/iterators/Makefile > >> installs the headers properly when building. > > > > CI complains when trying to build > > kernel/bpf/preload/iterators/iterators.o. I'll look more into this. > > My error was in fact on the previous patch for kernel/preload/Makefile, > where iterators.o is handled. The resulting Makefile in my v1 contained: > > bpf_preload_umd-objs := iterators/iterators.o > bpf_preload_umd-userldlibs := $(LIBBPF_A) -lelf -lz > > $(obj)/bpf_preload_umd: $(LIBBPF_A) > > This declares a dependency on $(LIBBPF_A) for building the final > bpf_preload_umd target, when iterators/iterators.o is linked against the > libraries. It does not declare the dependency for iterators/iterators.o > itself. So when we attempt to build the object file, libbpf has not been > compiled yet (not an issue per se), and the API headers from libbpf have > not been installed and made available to iterators.o, causing the build > to fail. > > Before this patch, there was no issue because the headers would be > included directly from tools/lib/bpf, so they would always be present. > I'll fix this by adding the relevant dependency, and send a v2. > > As a side note, I couldn't reproduce the issue locally or in the VM for > the selftests, I'm not sure why. I struggled to get helpful logs from > the kernel CI (kernel build in non-verbose mode), so I ended up copying > the CI infra (running on kernel-patches/bpf on GitHub) to my own GitHub > repository to add debug info and do other runs without re-posting every > time to the mailing list. In case anyone else is interested, I figured I > might share the steps: > > - Clone the linux repo on GitHub, push the bpf-next branch > - Copy all files and directories from the kernel-patches/vmtest GitHub > repo (including the .github directory) to the root of my linux repo, on > my development branch. > - Update the checks on "kernel-patches/bpf" repository name in > .github/workflows/test.yaml, to avoid pulling new Linux sources and > overwriting the files on my branch. > - (Add as much build debug info as necessary.) > - Push the branch to GitHub and open a PR against my own bpf-next > branch. This should trigger the Action. > > Or was there a simpler way to test my set on the CI, that I ignore? Don't know, I never tried :) But maybe Yucong (cc'ed) knows some tips and tricks? > > Quentin
