Re: [PATCH v2 3/4] arm64: vdso32: Fix compilation warning

[Catalin Marinas]

On Thu, Sep 26, 2019 at 02:38:04PM +0100, Vincenzo Frascino wrote:
> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
> index b61b50bf68b1..cfa9cd87af14 100644
> --- a/arch/arm64/include/asm/memory.h
> +++ b/arch/arm64/include/asm/memory.h
> @@ -228,11 +228,16 @@ static inline unsigned long kaslr_offset(void)
>  #define __tag_get(addr)		0
>  #endif /* CONFIG_KASAN_SW_TAGS */
>  
> +#ifdef __aarch64__
>  static inline const void *__tag_set(const void *addr, u8 tag)
>  {
>  	u64 __addr = (u64)addr & ~__tag_shifted(0xff);
>  	return (const void *)(__addr | __tag_shifted(tag));
>  }
> +#else
> +/* Unused in compat vdso */
> +#define __tag_set(addr, tag) 0
> +#endif

Do we actually need an #else block here? I think the #ifdef is
sufficient, with a comment along the lines of "Do not attempt to compile
when included in the compat vdso" (or pick some better wording).

-- 
Catalin