Option CONFIG_DEBUG_SET_MODULE_RONX not working for kernel 3.10

[Chetan Nanda]

On Fri, Aug 15, 2014 at 4:19 PM, Paul Bolle <pebolle at tiscali.nl> wrote:
> On Thu, 2014-08-14 at 09:38 -0400, Valdis Kletnieks wrote:
>> On Thu, 14 Aug 2014 16:46:22 +0530, Chetan Nanda said:
>> > I am trying to enable 'CONFIG_DEBUG_SET_MODULE_RONX' config option on
>> > 3.10 kernel (for ARM arch) via writing  CONFIG_DEBUG_SET_MODULE_RONX=y
>> > at the end of
>> > board specific config file.
>> >
>> > But .config generated after kernel build do not have this option enabled.
>> >
>> > Do I need to enable any other option also before enabling this one?
>>
>> Go into 'make menuconfig', Enter a '/'.  In the textbox, enter a substring
>> of the symbol (I entered 'MODULE_RONX').
>>
>> At least on x86_64, this shows me:
>>
>>   x Symbol: DEBUG_SET_MODULE_RONX [=y]                                                                                                  x
>>   x Type  : boolean                                                                                                                     x
>>   x Prompt: Set loadable kernel module data as NX and text as RO                                                                        x
>>   x   Location:                                                                                                                         x
>>   x (1) -> Kernel hacking                                                                                                               x
>>   x   Defined at arch/x86/Kconfig.debug:112                                                                                             x
>>   x   Depends on: MODULES [=y]
>>
>> Perhaps it's different on ARM - seems pretty silly to enable MODULE_RONX
>> if your kernel doesn't have CONFIG_MODULES=y in the build.
>
> DEBUG_SET_MODULE_RONX was added for ARM in v3.14:
> $ git grep -nw DEBUG_SET_MODULE_RONX v3.13
> v3.13:arch/s390/Kconfig.debug:32:config DEBUG_SET_MODULE_RONX
> v3.13:arch/x86/Kconfig.debug:103:config DEBUG_SET_MODULE_RONX
> $ git grep -nw DEBUG_SET_MODULE_RONX v3.14
> v3.14:arch/arm/Kconfig.debug:1198:config DEBUG_SET_MODULE_RONX
> v3.14:arch/s390/Kconfig.debug:32:config DEBUG_SET_MODULE_RONX
> v3.14:arch/x86/Kconfig.debug:103:config DEBUG_SET_MODULE_RONX
>
> See commit dca9aa92fc7c ("ARM: add DEBUG_SET_MODULE_RONX option to
> Kconfig"). So using that Kconfig symbol in v3.10 is pointless (for ARM).
>
>> But in general, you should *NOT* simply edit the config file, because
>> that does *not* do any checking of select/depend as you make the change.
>>
>> Then when you actually make the kernel, it *will* re-drive the select/depend
>> logic, and convert the provided .config to a self-consistent form.
>
> And, as Chetan noticed, it will also drop Kconfig symbols that are
> unknown for that build (as, in this case, DEBUG_SET_MODULE_RONX).
>
>> Of course,
>> there is zero guarantee that the self-consistent form corresponds to your
>> intentions....
>
Hi Valdis, Paul,

Thanks for your mails.
I would try to backport 'DEBUG_SET_MODULE_RONX' support from v3.14

Thanks,
Chetan Nanda
>
> Paul Bolle
>