eBPF is often used for kernel debugging, and one of the widely used and powerful debugging techniques is post-mortem debugging with a full memory dump. Triggering a panic at exactly the right moment allows the user to get such a dump and thus a better view at the system's state. This patchset adds bpf_panic() helper to do exactly that. I realize that even though there are multiple guards present, a helper like this is contrary to BPF being "safe", so this is sent as RFC to have a discussion on whether adding destructive capabilities is deemed acceptable. Artem Savkov (4): bpf: add a sysctl to enable destructive bpf helpers bpf: add BPF_F_DESTRUCTIVE flag for BPF_PROG_LOAD bpf: add bpf_panic() helper selftests/bpf: bpf_panic selftest include/linux/bpf.h | 8 + include/uapi/linux/bpf.h | 13 ++ kernel/bpf/core.c | 1 + kernel/bpf/helpers.c | 13 ++ kernel/bpf/syscall.c | 33 +++- kernel/bpf/verifier.c | 7 + kernel/trace/bpf_trace.c | 2 + tools/include/uapi/linux/bpf.h | 13 ++ .../selftests/bpf/prog_tests/bpf_panic.c | 144 ++++++++++++++++++ 9 files changed, 233 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/bpf_panic.c -- 2.35.3
