Re: [PATCH v2 0/5] vDSO: Use 32-bit CHECKFLAGS for compat vDSO

[Christophe Leroy (CS GROUP)]

Le 02/03/2026 à 08:58, Thomas Weißschuh a écrit :
> When building the compat vDSO the CHECKFLAGS from the 64-bit kernel
> are used. These are combined with the 32-bit CFLAGS. This confuses
> sparse, producing false-positive warnings or potentially missing
> real issues.
>
> Manually override the CHECKFLAGS for the compat vDSO with the correct
> 32-bit configuration.
>
> Not all architectures are supported, as many do not use sparse for their
> (compat) vDSO. These can be enabled later.
>
> Also add some checks to bitsperlong.h to detect such issues earlier.
>
> Based on tip/timers/vdso.
>
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
> ---
> Changes in v2:
> - Simplify __BITS_PER_LONG consistency checks
> - Fix an inconsistency in the powerpc audit code

The powerpc audit code should be replaced by generic 
AUDIT_ARCH_COMPAT_GENERIC, as there is no difference between them 
apparently.

A tentative was made in the past but was declined by audit maintainers 
because we were not able to test it allthought the failure was the same 
before and after the patch, see 
https://github.com/linuxppc/issues/issues/412

Christophe