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Date: Tue, 5 Nov 2013 08:13:10 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
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Subject: Re: [PATCH -tip v2 3/3] [BUGFIX] kprobes: Prohibit probing on
 func_ptr_is_kernel_text
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On Tue, 5 Nov 2013 08:05:37 +0100
Ingo Molnar <mingo@kernel.org> wrote:

> The macro magic I can think of would need to change the syntax of the 
> function definition - for example that is how the SYSCALL_DEFINE*() macros 
> work.

Or something like the EXPORT_SYMBOL(), but that wouldn't include the
size of the function. But using the name we could use kallsyms to see
if a probe is placed in a function that is blacklisted. Not very pretty
to do though.

> 
> It would be nice if there was a GCC extension that marked a function 
> noinline and allowed the emitting of the function's address (and size) 
> into a special section - but I'm not aware of any such compiler feature 
> today.

Yeah, I was wishing the same thing. Maybe I'll try to talk with the gcc
folks about adding such a feature. Something like

void  __attribute__((save_loc_and_size(".section"))) function(void)
{
}

-- Steve