Re: [PATCH v2 2/3] selftests/mm: emit TAP header and use TAP skip in mremap_test

From: Lorenzo Stoakes (ARM)

Date: Mon Aug 17 2026 - 12:46:49 EST


On Sat, Aug 15, 2026 at 04:07:15PM +0800, Song Hu wrote:
> mremap_test calls ksft_set_plan() without ksft_print_header(), and its
> get_mmap_min_addr() skip path uses a bare exit(KSFT_SKIP) that prints no
> TAP line, so its output is not valid KTAP. Add the header and switch
> the skip to ksft_exit_skip().
>
> Also fix two more KTAP compliance issues spotted in review:
>
> - get_mmap_min_addr() calls strerror(errno) after fclose(), which may
> clobber errno; save errno before fclose() instead.
>
> - Some ksft_*() messages embed "\n\t", so the text after each embedded
> newline is printed without the "# " prefix. Split those into separate
> messages.
>
> Acked-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
> Reviewed-by: Sarthak Sharma <sarthak.sharma@xxxxxxx>
> Signed-off-by: Song Hu <husong@xxxxxxxxxx>

All LGTM so:

Acked-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>

> ---
> tools/testing/selftests/mm/mremap_test.c | 41 +++++++++++++-----------
> 1 file changed, 23 insertions(+), 18 deletions(-)
>
> diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c
> index 131d9d6db867..28f151daabe4 100644
> --- a/tools/testing/selftests/mm/mremap_test.c
> +++ b/tools/testing/selftests/mm/mremap_test.c
> @@ -111,18 +111,17 @@ static unsigned long long get_mmap_min_addr(void)
> return addr;
>
> fp = fopen("/proc/sys/vm/mmap_min_addr", "r");
> - if (fp == NULL) {
> - ksft_print_msg("Failed to open /proc/sys/vm/mmap_min_addr: %s\n",
> - strerror(errno));
> - exit(KSFT_SKIP);
> - }
> + if (!fp)
> + ksft_exit_skip("Failed to open /proc/sys/vm/mmap_min_addr: %s\n",
> + strerror(errno));
>
> n_matched = fscanf(fp, "%llu", &addr);
> if (n_matched != 1) {
> - ksft_print_msg("Failed to read /proc/sys/vm/mmap_min_addr: %s\n",
> - strerror(errno));
> + int err = errno;
> +
> fclose(fp);
> - exit(KSFT_SKIP);
> + ksft_exit_skip("Failed to read /proc/sys/vm/mmap_min_addr: %s\n",
> + strerror(err));
> }
>
> fclose(fp);
> @@ -1164,10 +1163,11 @@ static void run_mremap_test_case(struct test test_case, int *failures,
> rand_addr);
>
> if (remap_time < 0) {
> - if (test_case.expect_failure)
> - ksft_test_result_xfail("%s\n\tExpected mremap failure\n",
> - test_case.name);
> - else {
> + if (test_case.expect_failure) {
> + ksft_print_msg("%s: expected mremap failure\n",
> + test_case.name);
> + ksft_test_result_xfail("%s\n", test_case.name);
> + } else {
> ksft_test_result_fail("%s\n", test_case.name);
> *failures += 1;
> }
> @@ -1177,11 +1177,13 @@ static void run_mremap_test_case(struct test test_case, int *failures,
> * was faulted in.
> */
> if (threshold_mb == VALIDATION_NO_THRESHOLD ||
> - test_case.config.region_size <= threshold_mb * _1MB)
> - ksft_test_result_pass("%s\n\tmremap time: %12lldns\n",
> - test_case.name, remap_time);
> - else
> + test_case.config.region_size <= threshold_mb * _1MB) {
> + ksft_print_msg("%s: mremap time: %12lldns\n",
> + test_case.name, remap_time);
> ksft_test_result_pass("%s\n", test_case.name);
> + } else {
> + ksft_test_result_pass("%s\n", test_case.name);
> + }
> }
> }
>
> @@ -1250,13 +1252,16 @@ int main(int argc, char **argv)
> time_t t;
> FILE *maps_fp;
>
> + ksft_print_header();
> +
> pattern_seed = (unsigned int) time(&t);
>
> if (parse_args(argc, argv, &threshold_mb, &pattern_seed) < 0)
> exit(EXIT_FAILURE);
>
> - ksft_print_msg("Test configs:\n\tthreshold_mb=%u\n\tpattern_seed=%u\n\n",
> - threshold_mb, pattern_seed);
> + ksft_print_msg("Test configs:\n");
> + ksft_print_msg("threshold_mb=%u\n", threshold_mb);
> + ksft_print_msg("pattern_seed=%u\n", pattern_seed);
>
> /*
> * set preallocated random array according to test configs; see the
> --
> 2.43.0
>

--
Cheers, Lorenzo