Re: [PATCH v11 04/12] scs: disable when function graph tracing is enabled

From: Steven Rostedt
Date: Mon Apr 20 2020 - 15:23:11 EST


On Fri, 17 Apr 2020 16:46:14 +0100
Mark Rutland <mark.rutland@xxxxxxx> wrote:

> > > > And doesn't BPF also do stuff like this?
> > >
> > > Can BPF mess with return addresses now!?
> >
> > At least on x86 I think it does. But what do I know, I can't operate
> > that stuff. Rostedt might know.
>
> Sounds like I might need to do some digging...

May want to ping Alexei. It appears that if BPF adds a direct hook to a
function, it will prevent the function graph tracer from tracing it. :-/

-- Steve