Re: [PATCH v1 1/1] selftests: mm: uufd-unit-tests: remove a format warning in printf

[Muhammad Usama Anjum <usama.anjum@collabora.com>]

The fix has already been picked up by Andew in mm unstable:

https://lore.kernel.org/all/20230607023727.0E011C433D2@smtp.kernel.org

On 6/11/23 4:50 AM, Mirsad Todorovac wrote:
> GCC 11.3.0 issued warnings about macros and types of arguments [edited]:
> 
> gcc -Wall -I ../tools/testing/selftests/../../.. \
> 	-I ../tools/testing/selftests/../../../tools/include/uapi \
> 	-isystem ../usr/include -no-pie uffd-unit-tests.c vm_util.c \
> 	uffd-common.c -lrt -lpthread -o \
> 	../tools/testing/selftests/mm/uffd-unit-tests
> uffd-unit-tests.c: In function ‘main’:
> uffd-unit-tests.c:1198:41: warning: format not a string literal and no \
> 	format arguments [-Wformat-security]
>  1198 |                         uffd_test_start(test_name);
>       |                                         ^~~~~~~~~
> uffd-unit-tests.c:100:24: note: in definition of macro ‘uffd_test_start’
>   100 |                 printf(__VA_ARGS__);            \
>       |                        ^~~~~~~~~~~
> uffd-unit-tests.c:1205:33: warning: format not a string literal and no \
> 	format arguments [-Wformat-security]
>  1205 |                                 uffd_test_skip(errmsg);
>       |                                 ^~~~~~~~~~~~~~
> 
> The macros are defined as:
> 
>  #define  uffd_test_start(...)  do {             \
>                 printf("Testing ");             \
>                 printf(__VA_ARGS__);            \
>                 printf("... ");                 \
>                 fflush(stdout);                 \
>         } while (0)
> 
>  #define  uffd_test_skip(...)  do {              \
>                 printf("skipped [reason: ");    \
>                 printf(__VA_ARGS__);            \
>                 printf("]\n");                  \
>                 ksft_inc_xskip_cnt();           \
>         } while (0)
> 
> Minor workaround, adding "%s" first argument to macro expansion calls seems
> to be the easiest way to eliminate the warnings.
> 
> Cc: Peter Xu <peterx@redhat.com>
> Cc: linux-mm@kvack.org
> Cc: linux-kselftest@vger.kernel.org
> Fixes: 43759d44dc34 ("selftests/mm: add uffdio register ioctls test")
> Fixes: 16a45b57cbf2 ("selftests/mm: add framework for uffd-unit-test")
> Signed-off-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
> ---
>  tools/testing/selftests/mm/uffd-unit-tests.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
> index 269c86768a02..d356dd271c84 100644
> --- a/tools/testing/selftests/mm/uffd-unit-tests.c
> +++ b/tools/testing/selftests/mm/uffd-unit-tests.c
> @@ -1195,14 +1195,14 @@ int main(int argc, char *argv[])
>  			snprintf(test_name, sizeof(test_name),
>  				 "%s on %s", test->name, mem_type->name);
>  
> -			uffd_test_start(test_name);
> +			uffd_test_start("%s", test_name);
>  			if (!uffd_feature_supported(test)) {
>  				uffd_test_skip("feature missing");
>  				continue;
>  			}
>  			if (uffd_setup_environment(&args, test, mem_type,
>  						   &errmsg)) {
> -				uffd_test_skip(errmsg);
> +				uffd_test_skip("%s", errmsg);
>  				continue;
>  			}
>  			test->uffd_fn(&args);

-- 
BR,
Muhammad Usama Anjum