Re: [PATCH v3 5/6] x86/ftrace: Use text_poke()

From: Peter Zijlstra
Date: Fri Oct 11 2019 - 09:45:53 EST


On Fri, Oct 11, 2019 at 09:33:19AM -0400, Steven Rostedt wrote:
> On Fri, 11 Oct 2019 14:59:03 +0200
> Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> > On Thu, Oct 10, 2019 at 07:28:19PM +0200, Peter Zijlstra wrote:
> >
> > > Really the best solution is to move all the poking into
> > > ftrace_module_init(), before we mark it RO+X. That's what I'm going to
> > > do for jump_label and static_call as well, I just need to add that extra
> > > notifier callback.
> >
> > OK, so I started writing that patch... or rather, I wrote the patch and
> > started on the Changelog when I ran into trouble describing why we need
> > it.
> >
> > That is, I'm struggling to explain why we cannot flip
> > prepare_coming_module() and complete_formation().
> >
> > Yes, it breaks ftrace, but I'm thinking that is all it breaks. So let me
> > see if we can cure that.
>
> For someone that doesn't use modules, you are making me very nervous
> with all the changes you are making to the module code! ;-)

Hey, today I build a kernel with modules just for you :-)

And whatever it takes right, I just want to clean this crap up.