Re: [patch 06/11] Text Edit Lock - Alternative code for x86

pageexec
2007-12-06T13:21:27Z

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?