Re: [PATCH] userfaultfd: selftests: make __{s,u}64 format specifiers portable

[Peter Xu]

Hi, Axel,

Looks mostly good to me, but a few nitpickings below.

On Wed, Dec 02, 2020 at 01:15:42PM -0800, Axel Rasmussen wrote:

[...]

> +static void uffd_error(const char *message, __s64 code)
> +{
> +	fprintf(stderr, "%s: %" PRId64 "\n", message, (int64_t)code);
> +	exit(1);
> +}

IMHO a macro that can take arbitrary parameters would be nicer, but if it
satisfy our need, definitely ok too.

[...]

> @@ -340,7 +348,8 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp)
>  	prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0;
>  
>  	if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms)) {
> -		fprintf(stderr, "clear WP failed for address 0x%Lx\n", start);
> +		fprintf(stderr, "clear WP failed for address 0x%" PRIx64 "\n",
> +			(uint64_t)start);
>  		exit(1);

Is it intended to not use uffd_error() here?

>  	}
>  }

[...]

> @@ -979,26 +981,20 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry)
>  	if (ret) {
>  		/* real retval in ufdio_zeropage.zeropage */
>  		if (has_zeropage) {
> -			if (uffdio_zeropage.zeropage == -EEXIST) {
> -				fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n");
> -				exit(1);
> -			} else {
> -				fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n",
> -					uffdio_zeropage.zeropage);
> -				exit(1);
> -			}
> +			uffd_error(uffdio_zeropage.zeropage == -EEXIST ?
> +						 "UFFDIO_ZEROPAGE -EEXIST" :
> +						 "UFFDIO_ZEROPAGE error",

Nit: The indents here are a bit odd..

Thanks,

-- 
Peter Xu