Date: Tue, 30 Jun 2009 06:29:39 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: James Morris <jmorris@namei.org>,
       Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
       linux-security-module@vger.kernel.org, Andi Kleen <ak@muc.de>,
       Rusty Russell <rusty@rustcorp.com.au>,
       Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>,
       Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH v2] RO/NX protection for loadable kernel modules
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On Tue, 30 Jun 2009 09:11:33 -0400
Siarhei Liakh <sliakh.lkml@gmail.com> wrote:

> > (and one can still argue that making this an option is not even
> > worth that, and just always do it unconditional)
> >
> 
> I can make NX unconditional. However, it will not reduce the number
> of #ifdefs. There are two of them in the patch right now: one
> controls the inclusion of two extra fields (init_ro_size,
> core_ro_size) in struct module, and the other one controls the
> inclusion of ALL patch code. The *_ro_size fields are used only for
> RO, and are not used to set NX. Therefore, this #ifdef will stay even
> if NX is unconditional. Since the second #ifdef controls ALL of the
> patch's code it will also stay (to control RO part) when NX becomes
> unconditional.
> 
> Given that it will not reduce the number of #ifdefs, do you still
> think that NX should be made unconditional?

I think that not only NX should be made unconditional, I also think
that the RO code should be unconditional.

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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