Re: [PATCH 6/9] ARM: uaccess: avoid warning for NOMMU in access_ok

From: Nicolas Pitre
Date: Thu Feb 18 2016 - 11:15:38 EST


On Thu, 18 Feb 2016, Arnd Bergmann wrote:

> When CONFIG_MMU is disabled, the access_ok() and __range_ok()
> macros always return success, and there is a cast to void
> to ensure the compiler does not warn about an unused address
> variable. However, at least one driver has a variable for
> the size argument as well and does warn about that one:
>
> drivers/vhost/vhost.c: In function 'vq_access_ok':
> drivers/vhost/vhost.c:633:9: warning: unused variable 's' [-Wunused-variable]
>
> This changes the macro to also ignore the size argument
> explicitly to shut up that warning.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>

> ---
> arch/arm/include/asm/uaccess.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
> index 35c9db857ebe..9c74c84a10d2 100644
> --- a/arch/arm/include/asm/uaccess.h
> +++ b/arch/arm/include/asm/uaccess.h
> @@ -290,7 +290,7 @@ extern int __put_user_8(void *, unsigned long long);
>
> #define segment_eq(a, b) (1)
> #define __addr_ok(addr) ((void)(addr), 1)
> -#define __range_ok(addr, size) ((void)(addr), 0)
> +#define __range_ok(addr, size) ((void)(addr), (void)(size), 0)
> #define get_fs() (KERNEL_DS)
>
> static inline void set_fs(mm_segment_t fs)
> --
> 2.7.0
>
>