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 */
fork_test_c(void)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
main(int argc,char ** argv)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\n");
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