1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2022 ARM Limited. 4 * Original author: Mark Brown <broonie@kernel.org> 5 */ 6 7 // SPDX-License-Identifier: GPL-2.0-only 8 9 #include <linux/sched.h> 10 #include <linux/wait.h> 11 12 #include "kselftest.h" 13 14 #define EXPECTED_TESTS 1 15 16 int fork_test(void); 17 int verify_fork(void); 18 19 /* 20 * If we fork the value in the parent should be unchanged and the 21 * child should start with the same value. This is called from the 22 * fork_test() asm function. 23 */ 24 int fork_test_c(void) 25 { 26 pid_t newpid, waiting; 27 int child_status, parent_result; 28 29 newpid = fork(); 30 if (newpid == 0) { 31 /* In child */ 32 if (!verify_fork()) { 33 ksft_print_msg("ZA state invalid in child\n"); 34 exit(0); 35 } else { 36 exit(1); 37 } 38 } 39 if (newpid < 0) { 40 ksft_print_msg("fork() failed: %d\n", newpid); 41 42 return 0; 43 } 44 45 parent_result = verify_fork(); 46 if (!parent_result) 47 ksft_print_msg("ZA state invalid in parent\n"); 48 49 for (;;) { 50 waiting = waitpid(newpid, &child_status, 0); 51 52 if (waiting < 0) { 53 if (errno == EINTR) 54 continue; 55 ksft_print_msg("waitpid() failed: %d\n", errno); 56 return 0; 57 } 58 if (waiting != newpid) { 59 ksft_print_msg("waitpid() returned wrong PID\n"); 60 return 0; 61 } 62 63 if (!WIFEXITED(child_status)) { 64 ksft_print_msg("child did not exit\n"); 65 return 0; 66 } 67 68 return WEXITSTATUS(child_status) && parent_result; 69 } 70 } 71 72 int main(int argc, char **argv) 73 { 74 int ret, i; 75 76 ksft_print_header(); 77 ksft_set_plan(EXPECTED_TESTS); 78 79 ksft_print_msg("PID: %d\n", getpid()); 80 81 /* 82 * This test is run with nolibc which doesn't support hwcap and 83 * it's probably disproportionate to implement so instead check 84 * for the default vector length configuration in /proc. 85 */ 86 ret = open("/proc/sys/abi/sme_default_vector_length", O_RDONLY, 0); 87 if (ret >= 0) { 88 ksft_test_result(fork_test(), "fork_test"); 89 90 } else { 91 ksft_print_msg("SME not supported\n"); 92 for (i = 0; i < EXPECTED_TESTS; i++) { 93 ksft_test_result_skip("fork_test\n"); 94 } 95 } 96 97 ksft_finished(); 98 99 return 0; 100 } 101