Re: [RFC][PATCH] x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot up

[Steven Rostedt]

On Fri, 1 May 2020 00:17:06 -0500
Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:

> > Would it be easier to just call a new __text_poke_bp() which skips the
> > SYSTEM_BOOTING check, since you know the trampoline will always be
> > read-only?
> > 
> > Like:  
> 
> early_trace_init() is called after mm_init(), so I thought it might
> work, but I guess not:

Yeah, I was about to say that this happens before mm_init() ;-)

It's why we already have magic for enabling function tracing the first time.

Do you see anything wrong with this current solution? It probably needs
more comments, but I wanted to get acceptance on the logic before I go and
pretty it up and send a non RFC patch.

-- Steve