Re: [RFC PATCH -next V3 1/6] x86: fix function define in copy_mc_to_user

[Kefeng Wang]

On 2022/4/12 15:25, Tong Tiangen wrote:
> X86 has it's implementation of copy_mc_to_user but not use #define to
> declare.
>
> This may cause problems, for example, if other architectures open
> CONFIG_ARCH_HAS_COPY_MC, but want to use copy_mc_to_user() outside the
> architecture, the code add to include/linux/uaddess.h is as follows:
>
>      #ifndef copy_mc_to_user
>      static inline unsigned long __must_check
>      copy_mc_to_user(void *dst, const void *src, size_t cnt)
>      {
> 	    ...
>      }
>      #endif
>
> Then this definition will conflict with the implementation of X86 and cause
> compilation errors.
Does powerpc need this define?
> Fixes: ec6347bb4339 ("x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()")
> Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
> ---
>   arch/x86/include/asm/uaccess.h | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
> index f78e2b3501a1..e18c5f098025 100644
> --- a/arch/x86/include/asm/uaccess.h
> +++ b/arch/x86/include/asm/uaccess.h
> @@ -415,6 +415,7 @@ copy_mc_to_kernel(void *to, const void *from, unsigned len);
>   
>   unsigned long __must_check
>   copy_mc_to_user(void *to, const void *from, unsigned len);
> +#define copy_mc_to_user copy_mc_to_user
>   #endif
>   
>   /*