[PATCH v3] powerpc/64: Option to use ELFv2 ABI for big-endian kernels

[Nicholas Piggin]

Excerpts from Michal Suchánek's message of May 4, 2021 12:38 am:
> On Mon, May 03, 2021 at 01:37:57PM +0200, Andreas Schwab wrote:
>> Should this add a tag to the module vermagic?

Good question.

> 
> Would the modues link even if the vermagic was not changed?
> 
> I suppose something like this might do it.

Yeah I don't know how robust the loader would be to a mismatch. We could 
add this patch.

Thanks,
Nick

> 
> Thanks
> 
> Michal
> 
> diff --git a/arch/powerpc/include/asm/vermagic.h b/arch/powerpc/include/asm/vermagic.h
> index b054a8576e5d..3fdaacd7a743 100644
> --- a/arch/powerpc/include/asm/vermagic.h
> +++ b/arch/powerpc/include/asm/vermagic.h
> @@ -14,7 +14,14 @@
>  #define MODULE_ARCH_VERMAGIC_RELOCATABLE	""
>  #endif
>  
> +
> +#ifdef CONFIG_PPC64_BUILD_BIG_ENDIAN_ELF_V2_ABI
> +#define MODULE_ARCH_VERMAGIC_ELF_V2_ABI	"abi-elfv2 "
> +#else
> +#define MODULE_ARCH_VERMAGIC_ELF_V2_ABI	""
> +#endif
> +
>  #define MODULE_ARCH_VERMAGIC \
> -		MODULE_ARCH_VERMAGIC_FTRACE MODULE_ARCH_VERMAGIC_RELOCATABLE
> +		MODULE_ARCH_VERMAGIC_FTRACE MODULE_ARCH_VERMAGIC_RELOCATABLE MODULE_ARCH_VERMAGIC_ELF_V2_ABI
>  
>  #endif /* _ASM_VERMAGIC_H */
>