Re: [External] Re: [PATCH bpf-next v2 1/9] bpf: tracing: add support to record and check the accessed args

Steven Rostedt
2024-03-30T12:28:01Z

On Fri, 29 Mar 2024 16:28:33 -0700
Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:

> I thought I'll just ask instead of digging through code, sorry for
> being lazy :) Is there any way to pass pt_regs/ftrace_regs captured
> before function execution to a return probe (fexit/kretprobe)? I.e.,
> how hard is it to pass input function arguments to a kretprobe? That's
> the biggest advantage of fexit over kretprobe, and if we can make
> these original pt_regs/ftrace_regs available to kretprobe, then
> multi-kretprobe will effectively be this multi-fexit.

This should be possible with the updates that Masami is doing with the
fgraph code.

-- Steve