1// SPDX-License-Identifier: GPL-2.0-only
2
3#include <linux/wait.h>
4
5#define THIS_PROGRAM "./vstate_exec_nolibc"
6
7int main(int argc, char **argv)
8{
9	int rc, pid, status, test_inherit = 0;
10	long ctrl, ctrl_c;
11	char *exec_argv[2], *exec_envp[2];
12
13	if (argc > 1)
14		test_inherit = 1;
15
16	ctrl = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL);
17	if (ctrl < 0) {
18		puts("PR_RISCV_V_GET_CONTROL is not supported\n");
19		return ctrl;
20	}
21
22	if (test_inherit) {
23		pid = fork();
24		if (pid == -1) {
25			puts("fork failed\n");
26			exit(-1);
27		}
28
29		/* child  */
30		if (!pid) {
31			exec_argv[0] = THIS_PROGRAM;
32			exec_argv[1] = NULL;
33			exec_envp[0] = NULL;
34			exec_envp[1] = NULL;
35			/* launch the program again to check inherit */
36			rc = execve(THIS_PROGRAM, exec_argv, exec_envp);
37			if (rc) {
38				puts("child execve failed\n");
39				exit(-1);
40			}
41		}
42
43	} else {
44		pid = fork();
45		if (pid == -1) {
46			puts("fork failed\n");
47			exit(-1);
48		}
49
50		if (!pid) {
51			rc = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL);
52			if (rc != ctrl) {
53				puts("child's vstate_ctrl not equal to parent's\n");
54				exit(-1);
55			}
56			asm volatile (".option push\n\t"
57				      ".option arch, +v\n\t"
58				      "vsetvli x0, x0, e32, m8, ta, ma\n\t"
59				      ".option pop\n\t"
60				      );
61			exit(ctrl);
62		}
63	}
64
65	rc = waitpid(-1, &status, 0);
66
67	if (WIFEXITED(status) && WEXITSTATUS(status) == -1) {
68		puts("child exited abnormally\n");
69		exit(-1);
70	}
71
72	if (WIFSIGNALED(status)) {
73		if (WTERMSIG(status) != SIGILL) {
74			puts("child was terminated by unexpected signal\n");
75			exit(-1);
76		}
77
78		if ((ctrl & PR_RISCV_V_VSTATE_CTRL_CUR_MASK) != PR_RISCV_V_VSTATE_CTRL_OFF) {
79			puts("child signaled by illegal V access but vstate_ctrl is not off\n");
80			exit(-1);
81		}
82
83		/* child terminated, and its vstate_ctrl is off */
84		exit(ctrl);
85	}
86
87	ctrl_c = WEXITSTATUS(status);
88	if (test_inherit) {
89		if (ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT) {
90			if (!(ctrl_c & PR_RISCV_V_VSTATE_CTRL_INHERIT)) {
91				puts("parent has inherit bit, but child has not\n");
92				exit(-1);
93			}
94		}
95		rc = (ctrl & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) >> 2;
96		if (rc != PR_RISCV_V_VSTATE_CTRL_DEFAULT) {
97			if (rc != (ctrl_c & PR_RISCV_V_VSTATE_CTRL_CUR_MASK)) {
98				puts("parent's next setting does not equal to child's\n");
99				exit(-1);
100			}
101
102			if (!(ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT)) {
103				if ((ctrl_c & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) !=
104				    PR_RISCV_V_VSTATE_CTRL_DEFAULT) {
105					puts("must clear child's next vstate_ctrl if !inherit\n");
106					exit(-1);
107				}
108			}
109		}
110	}
111	return ctrl;
112}
113