Re: [PATCH] selftests: net: fix format warnings on 32-bit architectures

[Hangbin Liu]

On Tue, Nov 03, 2026 at 10:55:03AM -0500, Sasha Levin wrote:
> On 32-bit architectures ssize_t is an int, tv_sec is a long long with a
> 64-bit time_t, and uint64_t is not a size_t, so ipsec, txtimestamp and
> the tcp_ao library warn when printing them with %ld, %lu and %zu:
> 
>   txtimestamp.c:191:42: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type '__time64_t' {aka 'long long int'} [-Wformat=]
> 
> Print ssize_t with %zd, tv_sec as long long, and the net namespace
> cookies with PRIu64 as the rest of ftrace-tcp.c already does. While at
> it, print tv_nsec, a long, with %ld instead of %lu, and cast it to long,
> as it is a long long on x32.
> 
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> Found with a 32-bit build of the selftests with a 64-bit time_t (gcc 16
> and clang 21 with -m32 -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64);
> KernelCI's 32-bit arm builds show the same warnings. The changed files
> build without format warnings there now, and the x86_64 builds don't
> change. The other selftests get the same kind of fix in separate
> patches.
> 
>  tools/testing/selftests/net/ipsec.c                 | 2 +-
>  tools/testing/selftests/net/tcp_ao/lib/ftrace-tcp.c | 2 +-
>  tools/testing/selftests/net/txtimestamp.c           | 9 +++++----
>  3 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/tools/testing/selftests/net/ipsec.c b/tools/testing/selftests/net/ipsec.c
> index 89c32c354c008..ba8c36a93f176 100644
> --- a/tools/testing/selftests/net/ipsec.c
> +++ b/tools/testing/selftests/net/ipsec.c
> @@ -2030,7 +2030,7 @@ static int __write_desc(int test_desc_fd, struct xfrm_desc *desc)
>  	if (ret == sizeof(*desc))
>  		return 0;
>  
> -	pr_err("Writing test's desc failed %ld", ret);
> +	pr_err("Writing test's desc failed %zd", ret);
>  
>  	return -1;
>  }
> diff --git a/tools/testing/selftests/net/tcp_ao/lib/ftrace-tcp.c b/tools/testing/selftests/net/tcp_ao/lib/ftrace-tcp.c
> index 27403f8750547..cd93ff8965dda 100644
> --- a/tools/testing/selftests/net/tcp_ao/lib/ftrace-tcp.c
> +++ b/tools/testing/selftests/net/tcp_ao/lib/ftrace-tcp.c
> @@ -504,7 +504,7 @@ static int setup_tcp_trace_events(struct test_ftracer *tracer)
>  	size_t i;
>  	int ret;
>  
> -	filter = test_sprintf("net_cookie == %zu || net_cookie == %zu",
> +	filter = test_sprintf("net_cookie == %" PRIu64 " || net_cookie == %" PRIu64,
>  			      ns_cookie1, ns_cookie2);
>  	if (!filter)
>  		return -ENOMEM;
> diff --git a/tools/testing/selftests/net/txtimestamp.c b/tools/testing/selftests/net/txtimestamp.c
> index f7bdf30b78d9f..be1452d73b303 100644
> --- a/tools/testing/selftests/net/txtimestamp.c
> +++ b/tools/testing/selftests/net/txtimestamp.c
> @@ -188,12 +188,13 @@ static void __print_timestamp(const char *name, struct timespec *cur,
>  		return;
>  
>  	if (cfg_print_nsec)
> -		fprintf(stderr, "  %s: %lu s %lu ns (seq=%u, len=%u)",
> -				name, cur->tv_sec, cur->tv_nsec,
> +		fprintf(stderr, "  %s: %lld s %ld ns (seq=%u, len=%u)",
> +				name, (long long)cur->tv_sec, (long)cur->tv_nsec,
>  				key, payload_len);
>  	else
> -		fprintf(stderr, "  %s: %lu s %lu us (seq=%u, len=%u)",
> -				name, cur->tv_sec, cur->tv_nsec / NSEC_PER_USEC,
> +		fprintf(stderr, "  %s: %lld s %ld us (seq=%u, len=%u)",
> +				name, (long long)cur->tv_sec,
> +				(long)(cur->tv_nsec / NSEC_PER_USEC),
>  				key, payload_len);
>  
>  	if (cur != &ts_usr) {
> -- 
> 2.53.0
> 

Reviewed-by: Hangbin Liu <liuhangbin@xxxxxxxxxx>