Re: [PATCH RFC] kprobes: Remove MODULES dependency

[Jarkko Sakkinen]

On Fri, Jul 10, 2020 at 08:51:56AM -0700, Kees Cook wrote:
> On Fri, Jul 10, 2020 at 07:32:57PM +0900, Masami Hiramatsu wrote:
> > On Fri, 10 Jul 2020 02:45:19 +0300
> > Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> wrote:
> > > +#ifdef CONFIG_MODULES
> > >  	/* Lock modules while optimizing kprobes */
> > >  	mutex_lock(&module_mutex);
> > > +#endif
> > 
> > Hmm, can you reduce these "#ifdef CONFIG_MODULE"s ?
> > 
> > e.g. 
> > 
> > #ifdef CONFIG_MODULES
> > static void lock_modules(void)
> > {
> > 	mutex_lock(&module_mutex);
> > }
> > ...
> > #else
> > #define lock_modules() do { } while (0)
> > ...
> > #endif
> 
> I prefer using "static inline" for no-op functions just because they
> will maintain argument type validation by the compiler regardless of the
> CONFIG state (though it doesn't really matter here since it's void).
> 
> #else
> static inline lock_modules(void) { }
> #endif
> 
> -- 
> Kees Cook

Thanks Kees, good remark.

/Jarkko