Re: [PATCH v5 1/4] gcc-plugins: Add the initify gcc plugin

[Kees Cook]

On Mon, Mar 27, 2017 at 12:31 PM, Rasmus Villemoes
<linux@xxxxxxxxxxxxxxxxxx> wrote:
> On Mon, Mar 27 2017, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
>> On Mon, Mar 27, 2017 at 12:38 AM, Andrew Donnellan
>> <andrew.donnellan@xxxxxxxxxxx> wrote:
>>> On 01/02/17 07:24, Kees Cook wrote:
>>>>
>>>> From: Emese Revfy <re.emese@xxxxxxxxx>
>>>>
>>>> The kernel already has a mechanism to free up code and data memory that
>>>> is only used during kernel or module initialization.  This plugin will
>>>> teach the compiler to find more such code and data that can be freed
>>>> after initialization.
>>>
>>>
>>> Currently checking whether we can wire this up for powerpc without too many
>>> problems...
>>
>> Cool, thanks. FWIW, note that this plugin is a bit back-burnered at
>> the moment. I've got this in my -next tree still, but it needs some
>> rather large changes to how it does its annotations before Linus will
>> accept it.
>
> Why not just hardcode the annotations in the plugin itself? I'd expect
> just making it know about mem*, str*, and the various *printf/printk
> functions would get 90% of the benefits. The prototypes of these
> aren't gonna change anytime soon, so there's no compelling reason to
> keep the annotations with the declarations. The plugin can still do
> its sanity checking when it compiles a function with one of these names.

Yup, I think that's another entirely workable solution too. I just
meant to say that I don't have time at the moment to look at it (if
you want to, please do), and I think Emese is already happy with how
the annotations work, so I don't think she'd want to work on it either
(but she can correct me if I'm wrong).

-Kees

-- 
Kees Cook
Pixel Security