Hi Yong-Xuan,
On Wed, Oct 1, 2025 at 6:15 AM Yong-Xuan Wang yongxuan.wang@sifive.com wrote:
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: Yong-Xuan Wang yongxuan.wang@sifive.com
tools/testing/selftests/riscv/vector/Makefile | 5 +- .../selftests/riscv/vector/vstate_ptrace.c | 132 ++++++++++++++++++ 2 files changed, 136 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/riscv/vector/vstate_ptrace.c
diff --git a/tools/testing/selftests/riscv/vector/Makefile b/tools/testing/selftests/riscv/vector/Makefile index 6f7497f4e7b3..45f25e9dd264 100644 --- a/tools/testing/selftests/riscv/vector/Makefile +++ b/tools/testing/selftests/riscv/vector/Makefile @@ -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 vsate_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) $^diff --git a/tools/testing/selftests/riscv/vector/vstate_ptrace.c b/tools/testing/selftests/riscv/vector/vstate_ptrace.c new file mode 100644 index 000000000000..8a7bcf318e59 --- /dev/null +++ b/tools/testing/selftests/riscv/vector/vstate_ptrace.c @@ -0,0 +1,132 @@ +// 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""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, t;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;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 += 2;
Just nitpicking here, simply adding 2 may fail if the program is not compiled with C. You may either +=4 and use ".option norvc" in the asm or determine the size of ebreak by decoding it.
with or without the fix,
Reviewed-by: Andy Chiu andybnac@gmail.com