why bpf ringbuf can not be used in uprobe of libbpf? about libbpf-bootstrap HOT 4 CLOSED

It's not "incomplete functionality", it's illegal to use bpf_ringbuf_reserve() without corresponding bpf_ringbuf_submit(). See https://nakryiko.com/posts/bpf-ringbuf/ for some more details.

Thanks, man. You are right! when I use bpf_ringbuf_submit() and bpf_ringbuf_discard() to make sure that no resources(rb) are unreleased, the program works!

from libbpf-bootstrap.

You need to call bpf_ringbuf_submit() or bpf_ringbuf_discard() before BPF program returns. You should have seen BPF verifier log with more details.

from libbpf-bootstrap.

You need to call bpf_ringbuf_submit() or bpf_ringbuf_discard() before BPF program returns. You should have seen BPF verifier log with more details.

Yes, the functionality is incomplete. But my simple goal is let it run rather than crash. When it does not crash, I will finish the code. So, how to fix it to avoid crash? By the way, remove line below which in kernel space code, the program can run normally. But add this line, the program exit with error "ibbpf: load bpf program failed: Invalid argument".
__u64* e = bpf_ringbuf_reserve(&rb, sizeof(__u64), 0);

from libbpf-bootstrap.

It's not "incomplete functionality", it's illegal to use bpf_ringbuf_reserve() without corresponding bpf_ringbuf_submit(). See https://nakryiko.com/posts/bpf-ringbuf/ for some more details.

from libbpf-bootstrap.