Re: [PATCH RFC] kprobes: Remove MODULES dependency

Masami Hiramatsu
2020-07-10T13:18:14Z

On Fri, 10 Jul 2020 13:32:38 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> On Fri, Jul 10, 2020 at 07:32:57PM +0900, Masami Hiramatsu wrote:
> > > - page = module_alloc(PAGE_SIZE);
> > > + page = vmalloc(PAGE_SIZE);
> >
> > No, you can not use vmalloc here. The reason why we use module_alloc()
> > is to allocate the executable memory for trampoline code.
> > So, you need to use vmalloc_exec() instead.
>
> vmalloc_exec() would be broken too, also hch recently got rid of that
> thing.
>
> module_alloc() really is the only sane choice here.
>
> We should make module_alloc() unconditionally available, and maybe even
> rename it to text_alloc().

Agreed. As far as I know, ftrace and bpf also depends on module_alloc(),
so text_alloc() will help them too.

Thank you,

--
Masami Hiramatsu <mhiramat@kernel.org>