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Date: Thu, 06 Dec 2007 14:19:33 +0200
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Subject: Re: [patch 06/11] Text Edit Lock - Alternative code for x86
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CC: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
       Andi Kleen <andi@firstfloor.org>, Thomas Gleixner <tglx@linutronix.de>,
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On 5 Dec 2007 at 21:02, Mathieu Desnoyers wrote:

> Fix a memcpy that should be a text_poke (in apply_alternatives).
> 
> Use kernel_wp_save/kernel_wp_restore in text_poke to support DEBUG_RODATA
> correctly and so the CPU HOTPLUG special case can be removed.
> 
> Add text_poke_early, for alternatives and paravirt boot-time and module load
> time patching.
> 
> Notes:
> - we use a macro for kernel_wp_save/restore to mimic local_irq_save/restore: the
>   argument is passed without &.

sorry to chime in again, but lately i've been thinking that the
cr0 argument is not really needed if one can ensure that calls
to the kernel open/close macros won't nest (i checked and even
in the PaX case it's easy to ensure, even desirable in fact).

in your case it's also true for now and i can't think of a situation
where you'd really want to nest in the future (that'd mean opening
up the kernel while some complex piece of code runs, more complex
than a mere memset at least ;-). what do you think?