[PATCH 1/3] init: Declare rodata_enabled and mark_rodata_ro() at all time

[Luis Chamberlain]

On Tue, Jan 30, 2024 at 06:48:11PM +0100, Marek Szyprowski wrote:
> Dear All,
> 
> On 30.01.2024 12:03, Christophe Leroy wrote:
> > Le 30/01/2024 à 10:16, Chen-Yu Tsai a écrit :
> >> [Vous ne recevez pas souvent de courriers de wenst at chromium.org. D?couvrez pourquoi ceci est important ? https://aka.ms/LearnAboutSenderIdentification ]
> >>
> >> On Mon, Jan 29, 2024 at 12:09:50PM -0800, Luis Chamberlain wrote:
> >>> On Thu, Dec 21, 2023 at 10:02:46AM +0100, Christophe Leroy wrote:
> >>>> Declaring rodata_enabled and mark_rodata_ro() at all time
> >>>> helps removing related #ifdefery in C files.
> >>>>
> >>>> Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>
> >>> Very nice cleanup, thanks!, applied and pushed
> >>>
> >>>     Luis
> >> On next-20240130, which has your modules-next branch, and thus this
> >> series and the other "module: Use set_memory_rox()" series applied,
> >> my kernel crashes in some very weird way. Reverting your branch
> >> makes the crash go away.
> >>
> >> I thought I'd report it right away. Maybe you folks would know what's
> >> happening here? This is on arm64.
> > That's strange, it seems to bug in module_bug_finalize() which is
> > _before_ calls to module_enable_ro() and such.
> >
> > Can you try to revert the 6 patches one by one to see which one
> > introduces the problem ?
> >
> > In reality, only patch 677bfb9db8a3 really change things. Other ones are
> > more on less only cleanup.
> 
> I've also run into this issue with today's (20240130) linux-next on my 
> test farm. The issue is not fully reproducible, so it was a bit hard to 
> bisect it automatically. I've spent some time on manual testing and it 
> looks that reverting the following 2 commits on top of linux-next fixes 
> the problem:
> 
> 65929884f868 ("modules: Remove #ifdef CONFIG_STRICT_MODULE_RWX around 
> rodata_enabled")
> 677bfb9db8a3 ("module: Don't ignore errors from set_memory_XX()")
> 
> This in fact means that commit 677bfb9db8a3 is responsible for this 
> regression, as 65929884f868 has to be reverted only because the latter 
> depends on it. Let me know what I can do to help debugging this issue.

Thanks for the bisect, I've reset my tree to commit
3559ad395bf02 ("module: Change module_enable_{nx/x/ro}() to more
explicit names") for now then, so to remove those commits.

  Luis