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Subject: Re: [RFC] [PATCH 2.6.37-rc5-tip 11/20] 11: uprobes: slot
 allocation for uprobes
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
        Linux-mm <linux-mm@vger.kernel.org>,
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Date: Tue, 25 Jan 2011 14:56:16 +0100
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On Thu, 2010-12-16 at 15:29 +0530, Srikar Dronamraju wrote:
> +       /*
> +        * We keep the vma's vm_start rather than a pointer to the vma
> +        * itself.  The probed process or a naughty kernel module could make
> +        * the vma go away, and we must handle that reasonably gracefully.
> +        */
> +       unsigned long vaddr;            /* Page(s) of instruction slots */ 

You could simply refuse to let the user unmap that area and rogue kernel
modules aren't something you can do anything about anyway.

But yeah..