Re: [RFC 0/1] BPF tracing for arm64 using fprobe

From: Peter Zijlstra
Date: Mon Nov 21 2022 - 09:18:01 EST


On Mon, Nov 21, 2022 at 02:47:10PM +0100, KP Singh wrote:

> > > How do I know that a function return was modified by BPF? If I'm debugging
>
> You can list the BPF programs that are loaded in the kernel with
>
> # bpftool prog list

Only when you have access to the machine; most cases it's people sending
random splats by email.

> Also, the BPF programs show up in call stacks when you are debugging.

Only when it splats inside the BPF part, not when it splats after
because BPF changed semantics of a function.