Re: [PATCH v2 1/8] x86: vdso: Introduce asm/vdso/mman.h

["Arnd Bergmann" <arnd@arndb.de>]

On Thu, Sep 26, 2024, at 05:51, Christophe Leroy wrote:
> Le 25/09/2024 à 23:23, Arnd Bergmann a écrit :
>> I agree that moving the contents out of uapi/ into vdso/ namespace
>> is not a solution here because that removes the contents from
>> the installed user headers, but we still need to do something
>> to solve the issue.
>
> Should header inclusion be reworked so that only UAPI and VDSO pathes 
> are looked for when including headers in VDSO builds ?

I think that could work. Not sure how hard it will be to
get to that point, but I like the idea.

>> The easiest workaround I see for this particular file is to
>> move the contents of arch/{arm,arm64,parisc,powerpc,sparc,x86}/\
>> include/asm/mman.h into a different file to ensure that the
>> only existing file is the uapi/ one. Unfortunately this does
>> not help to avoid it regressing again in the future.
>
> Could we add a check in checkpatch.pl to ensure UAPI headers do not 
> include headers that exist both in UAPI and non-UAPI space in the future ?

That is a much weaker check, I suspect it won't actually catch
most regressions as it's too easy to ignore checkpatch warnings.

     Arnd