Re: [PATCH RFC 0/4] Add support to directly attach BPF program to ftrace

From: Alexei Starovoitov
Date: Tue Jul 16 2019 - 18:26:58 EST


On Tue, Jul 16, 2019 at 05:30:50PM -0400, Joel Fernandes wrote:
>
> I also thought about the pinning idea before, but we also want to add support
> for not just raw tracepoints, but also regular tracepoints (events if you
> will). I am hesitant to add a new BPF API just for creating regular
> tracepoints and then pinning those as well.

and they should be done through the pinning as well.

> I don't see why a new bpf node for a trace event is a bad idea, really.

See the patches for kprobe/uprobe FD-based api and the reasons behind it.
tldr: text is racy, doesn't scale, poor security, etc.

> tracefs is how we deal with trace events on Android.

android has made mistakes in the past as well.

> This is a natural extension to that and fits with the security model
> well.

I think it's the opposite.
I'm absolutely against text based apis.