On 28/3/26 05:39, Song Liu wrote: > On Thu, Mar 26, 2026 at 7:17 AM Leon Hwang <[email protected]> wrote: [...] >> @@ -3733,6 +3733,11 @@ static int bpf_tracing_prog_attach(struct bpf_prog >> *prog, >> tr = prog->aux->dst_trampoline; >> tgt_prog = prog->aux->dst_prog; >> } >> + if (prog->type == BPF_PROG_TYPE_EXT && >> + prog->aux->kprobe_write_ctx != tgt_prog->aux->kprobe_write_ctx) { >> + err = -EINVAL; >> + goto out_unlock; >> + } > > This also blocks uprobe+freplace when prog and tgt_prog have different > kprobe_write_ctx, right? Is this the expected behavior? >
Intuitively, yes, this also blocks uprobe+freplace. However, how can we distinguish uprobe/kprobe here? At attach time, uprobe/kprobe is recognized by the target perf event flags instead of BPF prog's expected_attach_type. Thus, we cannot infer the use of prog by prog itself. If we can distinguish them here, I'd like to do it. Thanks, Leon
