[PATCH 1/3] powerpc/64s: Fix build when !PPC_BARRIER_NOSPEC

[Christophe Leroy]

Le 16/08/2021 à 10:24, Joel Stanley a écrit :
> When disabling PPC_BARRIER_NOSPEC the do_barrier_nospec_fixups_range
> definition is still included, as well as a stub in asm/setup.h:
> 
> ../arch/powerpc/lib/feature-fixups.c:502:6: error: redefinition of ‘do_barrier_nospec_fixu>
>    502 | void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_en>
>        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> In file included from ../arch/powerpc/lib/feature-fixups.c:23:
> ../arch/powerpc/include/asm/setup.h:70:20: note: previous definition of ‘do_barrier_nospec>
>     70 | static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *>
>        |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> I assume the intent was to put the just do_barrier_nospec_fixups
> behind PPC_BARRIER_NOSPEC and let the compiler drop _range when there
> are no users. (There is a caller in module.c, but this is behind
> PPC_BARRIER_NOSPEC).

The compiler won't drop do_barrier_nospec_fixups_range() because it is not static.

> 
> This makes PPC_BOOK3S_64 match how the PPC_FSL_BOOK3E build works.
> 
> Signed-off-by: Joel Stanley <joel at jms.id.au>
> ---
>   arch/powerpc/include/asm/setup.h | 2 --
>   1 file changed, 2 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
> index 6c1a7d217d1a..71012284c044 100644
> --- a/arch/powerpc/include/asm/setup.h
> +++ b/arch/powerpc/include/asm/setup.h
> @@ -66,8 +66,6 @@ extern bool barrier_nospec_enabled;
>   
>   #ifdef CONFIG_PPC_BARRIER_NOSPEC
>   void do_barrier_nospec_fixups_range(bool enable, void *start, void *end);
> -#else
> -static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { }
>   #endif
>   
>   #ifdef CONFIG_PPC_FSL_BOOK3E
>