Commit f0ae09a8 authored by Yong-Xuan Wang's avatar Yong-Xuan Wang Committed by Paul Walmsley
Browse files

selftests: riscv: Add test for the Vector ptrace interface 



Add a test case that does some basic verification of the Vector ptrace
interface. This forks a child process then using ptrace to inspect and
manipulate the v31 register of the child.

Signed-off-by: default avatarYong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: default avatarAndy Chiu <andybnac@gmail.com>
Tested-by: default avatarAndy Chiu <andybnac@gmail.com>
Link: https://patch.msgid.link/20251013091318.467864-3-yongxuan.wang@sifive.com


Signed-off-by: default avatarPaul Walmsley <pjw@kernel.org>
parent 6efb1a94

tools/testing/selftests/riscv/vector/Makefile

+4 −1
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
# Copyright (C) 2021 ARM Limited

# Originally tools/testing/arm64/abi/Makefile



TEST_GEN_PROGS := v_initval vstate_prctl

TEST_GEN_PROGS := v_initval vstate_prctl vstate_ptrace

TEST_GEN_PROGS_EXTENDED := vstate_exec_nolibc v_exec_initval_nolibc



include ../../lib.mk
@@ -26,3 +26,6 @@ $(OUTPUT)/v_initval: v_initval.c $(OUTPUT)/sys_hwprobe.o $(OUTPUT)/v_helpers.o 
$(OUTPUT)/v_exec_initval_nolibc: v_exec_initval_nolibc.c

	$(CC) -nostdlib -static -include ../../../../include/nolibc/nolibc.h \

		-Wall $(CFLAGS) $(LDFLAGS) $^ -o $@ -lgcc



$(OUTPUT)/vstate_ptrace: vstate_ptrace.c $(OUTPUT)/sys_hwprobe.o $(OUTPUT)/v_helpers.o

	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^

tools/testing/selftests/riscv/vector/vstate_ptrace.c

0 → 100644
+134 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

#include <stdio.h>

#include <stdlib.h>

#include <asm/ptrace.h>

#include <linux/elf.h>

#include <sys/ptrace.h>

#include <sys/uio.h>

#include <sys/wait.h>

#include "../../kselftest.h"

#include "v_helpers.h"



int parent_set_val, child_set_val;



static long do_ptrace(enum __ptrace_request op, pid_t pid, long type, size_t size, void *data)

{

	struct iovec v_iovec = {

		.iov_len = size,

		.iov_base = data

	};



	return ptrace(op, pid, type, &v_iovec);

}



static int do_child(void)

{

	int out;



	if (ptrace(PTRACE_TRACEME, -1, NULL, NULL)) {

		ksft_perror("PTRACE_TRACEME failed\n");

		return EXIT_FAILURE;

	}



	asm volatile (".option push\n\t"

		".option	arch, +v\n\t"

		".option	norvc\n\t"

		"vsetivli	x0, 1, e32, m1, ta, ma\n\t"

		"vmv.s.x	v31, %[in]\n\t"

		"ebreak\n\t"

		"vmv.x.s	%[out], v31\n\t"

		".option pop\n\t"

		: [out] "=r" (out)

		: [in] "r" (child_set_val));



	if (out != parent_set_val)

		return EXIT_FAILURE;



	return EXIT_SUCCESS;

}



static void do_parent(pid_t child)

{

	int status;

	void *data = NULL;



	/* Attach to the child */

	while (waitpid(child, &status, 0)) {

		if (WIFEXITED(status)) {

			ksft_test_result(WEXITSTATUS(status) == 0, "SETREGSET vector\n");

			goto out;

		} else if (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP)) {

			size_t size;

			void *data, *v31;

			struct __riscv_v_regset_state *v_regset_hdr;

			struct user_regs_struct *gpreg;



			size = sizeof(*v_regset_hdr);

			data = malloc(size);

			if (!data)

				goto out;

			v_regset_hdr = (struct __riscv_v_regset_state *)data;



			if (do_ptrace(PTRACE_GETREGSET, child, NT_RISCV_VECTOR, size, data))

				goto out;



			ksft_print_msg("vlenb %ld\n", v_regset_hdr->vlenb);

			data = realloc(data, size + v_regset_hdr->vlenb * 32);

			if (!data)

				goto out;

			v_regset_hdr = (struct __riscv_v_regset_state *)data;

			v31 = (void *)(data + size + v_regset_hdr->vlenb * 31);

			size += v_regset_hdr->vlenb * 32;



			if (do_ptrace(PTRACE_GETREGSET, child, NT_RISCV_VECTOR, size, data))

				goto out;



			ksft_test_result(*(int *)v31 == child_set_val, "GETREGSET vector\n");



			*(int *)v31 = parent_set_val;

			if (do_ptrace(PTRACE_SETREGSET, child, NT_RISCV_VECTOR, size, data))

				goto out;



			/* move the pc forward */

			size = sizeof(*gpreg);

			data = realloc(data, size);

			gpreg = (struct user_regs_struct *)data;



			if (do_ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, size, data))

				goto out;



			gpreg->pc += 4;

			if (do_ptrace(PTRACE_SETREGSET, child, NT_PRSTATUS, size, data))

				goto out;

		}



		ptrace(PTRACE_CONT, child, NULL, NULL);

	}



out:

	free(data);

}



int main(void)

{

	pid_t child;



	ksft_set_plan(2);

	if (!is_vector_supported() && !is_xtheadvector_supported())

		ksft_exit_skip("Vector not supported\n");



	srandom(getpid());

	parent_set_val = rand();

	child_set_val = rand();



	child = fork();

	if (child < 0)

		ksft_exit_fail_msg("Fork failed %d\n", child);



	if (!child)

		return do_child();



	do_parent(child);



	ksft_finished();

}