Re: [PATCH v4 14/15] kprobes: remove dependency on CONFIG_MODULES

Christophe Leroy
2024-04-19T15:59:43Z

Le 19/04/2024 à 17:49, Mike Rapoport a écrit :
> Hi Masami,
>
> On Thu, Apr 18, 2024 at 06:16:15AM +0900, Masami Hiramatsu wrote:
>> Hi Mike,
>>
>> On Thu, 11 Apr 2024 19:00:50 +0300
>> Mike Rapoport <rppt@kernel.org> wrote:
>>
>>> From: "Mike Rapoport (IBM)" <rppt@kernel.org>
>>>
>>> kprobes depended on CONFIG_MODULES because it has to allocate memory for
>>> code.
>>>
>>> Since code allocations are now implemented with execmem, kprobes can be
>>> enabled in non-modular kernels.
>>>
>>> Add #ifdef CONFIG_MODULE guards for the code dealing with kprobes inside
>>> modules, make CONFIG_KPROBES select CONFIG_EXECMEM and drop the
>>> dependency of CONFIG_KPROBES on CONFIG_MODULES.
>>
>> Thanks for this work, but this conflicts with the latest fix in v6.9-rc4.
>> Also, can you use IS_ENABLED(CONFIG_MODULES) instead of #ifdefs in
>> function body? We have enough dummy functions for that, so it should
>> not make a problem.
>
> The code in check_kprobe_address_safe() that gets the module and checks for
> __init functions does not compile with IS_ENABLED(CONFIG_MODULES).
> I can pull it out to a helper or leave #ifdef in the function body,
> whichever you prefer.

As far as I can see, the only problem is MODULE_STATE_COMING.
Can we move 'enum module_state' out of #ifdef CONFIG_MODULES in module.h ?

>
>> --
>> Masami Hiramatsu
>