From: Mark Brown <broonie@xxxxxxxxxx> [ Upstream commit dca93d29845dfed60910ba13dbfb6ae6a0e19f6d ] Currently if we encounter an error between fork() and exec() of a child process we log the error to stderr. This means that the errors don't get annotated with the child information which makes diagnostics harder and means that if we miss the exit signal from the child we can deadlock waiting for output from the child. Improve robustness and output quality by logging to stdout instead. Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Link: https://lore.kernel.org/r/20241023-arm64-fp-stress-exec-fail-v1-1-ee3c62932c15@xxxxxxxxxx Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/arm64/fp/fp-stress.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/arm64/fp/fp-stress.c b/tools/testing/selftests/arm64/fp/fp-stress.c index faac24bdefeb9..80f22789504d6 100644 --- a/tools/testing/selftests/arm64/fp/fp-stress.c +++ b/tools/testing/selftests/arm64/fp/fp-stress.c @@ -79,7 +79,7 @@ static void child_start(struct child_data *child, const char *program) */ ret = dup2(pipefd[1], 1); if (ret == -1) { - fprintf(stderr, "dup2() %d\n", errno); + printf("dup2() %d\n", errno); exit(EXIT_FAILURE); } @@ -89,7 +89,7 @@ static void child_start(struct child_data *child, const char *program) */ ret = dup2(startup_pipe[0], 3); if (ret == -1) { - fprintf(stderr, "dup2() %d\n", errno); + printf("dup2() %d\n", errno); exit(EXIT_FAILURE); } @@ -107,16 +107,15 @@ static void child_start(struct child_data *child, const char *program) */ ret = read(3, &i, sizeof(i)); if (ret < 0) - fprintf(stderr, "read(startp pipe) failed: %s (%d)\n", - strerror(errno), errno); + printf("read(startp pipe) failed: %s (%d)\n", + strerror(errno), errno); if (ret > 0) - fprintf(stderr, "%d bytes of data on startup pipe\n", - ret); + printf("%d bytes of data on startup pipe\n", ret); close(3); ret = execl(program, program, NULL); - fprintf(stderr, "execl(%s) failed: %d (%s)\n", - program, errno, strerror(errno)); + printf("execl(%s) failed: %d (%s)\n", + program, errno, strerror(errno)); exit(EXIT_FAILURE); } else { -- 2.43.0