vstate_exec_nolibc.c

  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, xtheadvector = 0;
 10	long ctrl, ctrl_c;
 11	char *exec_argv[2], *exec_envp[2];
 12
 13	if (argc > 1 && strcmp(argv[1], "x"))
 14		test_inherit = 1;
 15
 16	if (argc > 2 && strcmp(argv[2], "x"))
 17		xtheadvector = 1;
 18
 19	ctrl = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL);
 20	if (ctrl < 0) {
 21		puts("PR_RISCV_V_GET_CONTROL is not supported\n");
 22		return ctrl;
 23	}
 24
 25	if (test_inherit) {
 26		pid = fork();
 27		if (pid == -1) {
 28			puts("fork failed\n");
 29			exit(-1);
 30		}
 31
 32		/* child  */
 33		if (!pid) {
 34			exec_argv[0] = THIS_PROGRAM;
 35			exec_argv[1] = NULL;
 36			exec_envp[0] = NULL;
 37			exec_envp[1] = NULL;
 38			/* launch the program again to check inherit */
 39			rc = execve(THIS_PROGRAM, exec_argv, exec_envp);
 40			if (rc) {
 41				puts("child execve failed\n");
 42				exit(-1);
 43			}
 44		}
 45
 46	} else {
 47		pid = fork();
 48		if (pid == -1) {
 49			puts("fork failed\n");
 50			exit(-1);
 51		}
 52
 53		if (!pid) {
 54			rc = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL);
 55			if (rc != ctrl) {
 56				puts("child's vstate_ctrl not equal to parent's\n");
 57				exit(-1);
 58			}
 59			if (xtheadvector)
 60				asm volatile (".4byte	0x00007ed7");
 61			else
 62				asm volatile (".option push\n\t"
 63					".option arch, +v\n\t"
 64					"vsetvli x0, x0, e32, m8, ta, ma\n\t"
 65					".option pop\n\t"
 66					);
 67			exit(ctrl);
 68		}
 69	}
 70
 71	rc = waitpid(-1, &status, 0);
 72
 73	if (WIFEXITED(status) && WEXITSTATUS(status) == -1) {
 74		puts("child exited abnormally\n");
 75		exit(-1);
 76	}
 77
 78	if (WIFSIGNALED(status)) {
 79		if (WTERMSIG(status) != SIGILL) {
 80			puts("child was terminated by unexpected signal\n");
 81			exit(-1);
 82		}
 83
 84		if ((ctrl & PR_RISCV_V_VSTATE_CTRL_CUR_MASK) != PR_RISCV_V_VSTATE_CTRL_OFF) {
 85			puts("child signaled by illegal V access but vstate_ctrl is not off\n");
 86			exit(-1);
 87		}
 88
 89		/* child terminated, and its vstate_ctrl is off */
 90		exit(ctrl);
 91	}
 92
 93	ctrl_c = WEXITSTATUS(status);
 94	if (test_inherit) {
 95		if (ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT) {
 96			if (!(ctrl_c & PR_RISCV_V_VSTATE_CTRL_INHERIT)) {
 97				puts("parent has inherit bit, but child has not\n");
 98				exit(-1);
 99			}
100		}
101		rc = (ctrl & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) >> 2;
102		if (rc != PR_RISCV_V_VSTATE_CTRL_DEFAULT) {
103			if (rc != (ctrl_c & PR_RISCV_V_VSTATE_CTRL_CUR_MASK)) {
104				puts("parent's next setting does not equal to child's\n");
105				exit(-1);
106			}
107
108			if (!(ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT)) {
109				if ((ctrl_c & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) !=
110				    PR_RISCV_V_VSTATE_CTRL_DEFAULT) {
111					puts("must clear child's next vstate_ctrl if !inherit\n");
112					exit(-1);
113				}
114			}
115		}
116	}
117	return ctrl;
118}