From: Andi Kleen <andi@firstfloor.org>
To: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org,
linux-next@vger.kernel.org,
Arjan van de Ven <arjan@infradead.org>,
James Morris <jmorris@namei.org>,
Andrew Morton <akpm@linux-foundation.org>, Andi Kleen <ak@muc.de>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@elte.hu>,
Rusty Russell <rusty@rustcorp.com.au>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Dave Jones <davej@redhat.com>
Subject: Re: [PATCH v8] RO/NX protection for loadable kernel modules
Date: Wed, 03 Feb 2010 00:05:39 +0100 [thread overview]
Message-ID: <873a1jdyrg.fsf@basil.nowhere.org> (raw)
In-Reply-To: <817ecb6f1001311522q52bf4eebmb748c486dcd5ad35@mail.gmail.com> (Siarhei Liakh's message of "Sun, 31 Jan 2010 18:22:35 -0500")
Siarhei Liakh <sliakh.lkml@gmail.com> writes:
> This patch is a logical extension of the protection provided by
> CONFIG_DEBUG_RODATA to LKMs. The protection is provided by splitting
> module_core and module_init into three logical parts each and setting
> appropriate page access permissions for each individual section:
My current kernel has 52 modules loaded, most of them very small.
Assuming the additional alignment of the data section cost two more
pages on average (I think that's a good assumption), that's roughly
424KB of additional memory, plus associated runtime costs in increased
TLB usage.
What would I get for that if I applied the patch and enabled the option?
That information seems to be missing in this patch submission.
Did you find any bugs with this option?
-Andi
--
ak@linux.intel.com -- Speaking for myself only.
next prev parent reply other threads:[~2010-02-02 23:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-31 23:22 [PATCH v8] RO/NX protection for loadable kernel modules Siarhei Liakh
2010-02-01 1:39 ` Rusty Russell
2010-02-01 16:22 ` Siarhei Liakh
2010-02-02 23:05 ` Andi Kleen [this message]
2010-02-03 4:07 ` Siarhei Liakh
2010-02-08 1:45 ` Rusty Russell
2010-02-08 1:54 ` H. Peter Anvin
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