Release bpftool v7.2 · libbpf/bpftool

Breaking change

When trying to dump the control flow graph (CFG) for a BPF program (bpftool prog dump xlated <program> visual), return an error if the user passed one of the --json or --pretty options, instead of simply ignoring the option.

Support printing the C source code (inline annotations), if available, in the CFGs for programs. Also support line numbers and opcodes in the CFGs with the linum and opcodes keywords, just like for regular program dumps.
In the Makefile's feature detection for the mirror repository, output the name, results, and stderr when probing features with V=1.

Fix linkage with statically built LLVM libraries for the disassembler for JIT-compiled BPF programs. Some flags and libraries were missing.
With bpftool prog profile, profile online CPUs instead of “possible” CPUs, given that some of the latter may not be online and hence not available for profiling.
In BPF-related feature probing, avoid marking kernel config option as not set if the kernel configuration file is not found.
In the Makefile, add missing quotes to libbpf bootstrap submake variables, to fix use cases where $(HOSTCC) is set to /usr/bin/ccache /usr/bin/gcc, for example.
Fix a bug in the JSON writer, which would produce an escaped line break instead of escaped backslash for a \ character.
Fix another bug in the JSON writer, about an invalid JSON escape for \'.
Fix bug for long instructions (such as loading a 64-bit long immediate into a register) not displayed properly in program CFG dumps.
Fix documentation about line information display for program dumps: the document hinted that displaying the source line could be turn off, and that the file name would be printed “on top of” the source line, but these indications were not accurate.
Ignore $(CFLAGS), use $(EXTRA_CFLAGS) in the Makefile's feature detection framework, thus mirroring the behavior of the kernel version. On top of that, fix feature detection for static builds.
Fix the feature detection system to account for $(FEATURE_TESTS) defined in the main Makefile.

Add static build instructions for bpftool in the README.md of the mirror repository.
Use bpf_{btf,link,map,prog}_get_info_by_fd() (wrappers around bpf_obj_get_info_by_fd()), to improve type safety in the code, and to help with the Memory Sanitizer.
Always disable stack protection for building BPF programs used by bpftool. If present, as is the default on Gentoo for example, stack protection for the clang toolchain would produce errors when trying to compile the relevant object files, but stack protection is not relevant in the case of BPF programs and it is safe to turn it off.

Add a release workflow to build and ship static binaries for amd64 and arm64 (and SHA256 sums) on releases (the workflow creates a draft release when tags are pushed, and attaches the assets). Also use this workflow to ship a tarball containing all sources required to compile (bpftool, plus libbpf submodule). Add a script to update GitHub labels for some of these release assets.
Add a workflow for static builds with both LLVM and libbfd disassemblers. The early version for the LLVM disassembler would include compiling the LLVM libraries and take around 80 minutes to complete, but later we switched to downloading libraries compatible with static linking from LLVM's CI, cutting down the duration for the workflow to about 2 minutes.
Remove deprecated Ubuntu 18.04 GitHub runner from the CI in the matrix for the build workflow.
In workflow definitions, add concurrency groups to cancel outdated runs.
Add path filters to workflow definitions, to avoid running all workflows if some are not relevant for a given Pull Request.
Add a CI workflow to make sure GitHub mirror commits have valid prefixes (mirror: or sync: or ci: only, so we can easily distinguish them from the commits coming from the kernel repository).
Switch to the Hadolint linter for checking the Dockerfile, and improve the related workflow.

Some features requiring the use of “skeletons” (feature-clang-bpf-co-re compilation option) require kernel 5.15 or more recent, with CONFIG_PERF_EVENTS set, to compile bpftool (#17).
Command bpftool cgroup tree may be broken when running with kernels under v6.1 (#41).

Full Changelog: v7.1.0...v7.2.0