linuxdebug/tools/testing/selftests/arm64/fp/sve-ptrace.c

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2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015-2021 ARM Limited.
* Original author: Dave Martin <Dave.Martin@arm.com>
*/
#include <errno.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/auxv.h>
#include <sys/prctl.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <asm/sigcontext.h>
#include <asm/ptrace.h>
#include "../../kselftest.h"
/* <linux/elf.h> and <sys/auxv.h> don't like each other, so: */
#ifndef NT_ARM_SVE
#define NT_ARM_SVE 0x405
#endif
#ifndef NT_ARM_SSVE
#define NT_ARM_SSVE 0x40b
#endif
struct vec_type {
const char *name;
unsigned long hwcap_type;
unsigned long hwcap;
int regset;
int prctl_set;
};
static const struct vec_type vec_types[] = {
{
.name = "SVE",
.hwcap_type = AT_HWCAP,
.hwcap = HWCAP_SVE,
.regset = NT_ARM_SVE,
.prctl_set = PR_SVE_SET_VL,
},
{
.name = "Streaming SVE",
.hwcap_type = AT_HWCAP2,
.hwcap = HWCAP2_SME,
.regset = NT_ARM_SSVE,
.prctl_set = PR_SME_SET_VL,
},
};
#define VL_TESTS (((SVE_VQ_MAX - SVE_VQ_MIN) + 1) * 4)
#define FLAG_TESTS 2
#define FPSIMD_TESTS 2
#define EXPECTED_TESTS ((VL_TESTS + FLAG_TESTS + FPSIMD_TESTS) * ARRAY_SIZE(vec_types))
static void fill_buf(char *buf, size_t size)
{
int i;
for (i = 0; i < size; i++)
buf[i] = random();
}
static int do_child(void)
{
if (ptrace(PTRACE_TRACEME, -1, NULL, NULL))
ksft_exit_fail_msg("PTRACE_TRACEME", strerror(errno));
if (raise(SIGSTOP))
ksft_exit_fail_msg("raise(SIGSTOP)", strerror(errno));
return EXIT_SUCCESS;
}
static int get_fpsimd(pid_t pid, struct user_fpsimd_state *fpsimd)
{
struct iovec iov;
iov.iov_base = fpsimd;
iov.iov_len = sizeof(*fpsimd);
return ptrace(PTRACE_GETREGSET, pid, NT_PRFPREG, &iov);
}
static int set_fpsimd(pid_t pid, struct user_fpsimd_state *fpsimd)
{
struct iovec iov;
iov.iov_base = fpsimd;
iov.iov_len = sizeof(*fpsimd);
return ptrace(PTRACE_SETREGSET, pid, NT_PRFPREG, &iov);
}
static struct user_sve_header *get_sve(pid_t pid, const struct vec_type *type,
void **buf, size_t *size)
{
struct user_sve_header *sve;
void *p;
size_t sz = sizeof *sve;
struct iovec iov;
while (1) {
if (*size < sz) {
p = realloc(*buf, sz);
if (!p) {
errno = ENOMEM;
goto error;
}
*buf = p;
*size = sz;
}
iov.iov_base = *buf;
iov.iov_len = sz;
if (ptrace(PTRACE_GETREGSET, pid, type->regset, &iov))
goto error;
sve = *buf;
if (sve->size <= sz)
break;
sz = sve->size;
}
return sve;
error:
return NULL;
}
static int set_sve(pid_t pid, const struct vec_type *type,
const struct user_sve_header *sve)
{
struct iovec iov;
iov.iov_base = (void *)sve;
iov.iov_len = sve->size;
return ptrace(PTRACE_SETREGSET, pid, type->regset, &iov);
}
/* Validate setting and getting the inherit flag */
static void ptrace_set_get_inherit(pid_t child, const struct vec_type *type)
{
struct user_sve_header sve;
struct user_sve_header *new_sve = NULL;
size_t new_sve_size = 0;
int ret;
/* First set the flag */
memset(&sve, 0, sizeof(sve));
sve.size = sizeof(sve);
sve.vl = sve_vl_from_vq(SVE_VQ_MIN);
sve.flags = SVE_PT_VL_INHERIT;
ret = set_sve(child, type, &sve);
if (ret != 0) {
ksft_test_result_fail("Failed to set %s SVE_PT_VL_INHERIT\n",
type->name);
return;
}
/*
* Read back the new register state and verify that we have
* set the flags we expected.
*/
if (!get_sve(child, type, (void **)&new_sve, &new_sve_size)) {
ksft_test_result_fail("Failed to read %s SVE flags\n",
type->name);
return;
}
ksft_test_result(new_sve->flags & SVE_PT_VL_INHERIT,
"%s SVE_PT_VL_INHERIT set\n", type->name);
/* Now clear */
sve.flags &= ~SVE_PT_VL_INHERIT;
ret = set_sve(child, type, &sve);
if (ret != 0) {
ksft_test_result_fail("Failed to clear %s SVE_PT_VL_INHERIT\n",
type->name);
return;
}
if (!get_sve(child, type, (void **)&new_sve, &new_sve_size)) {
ksft_test_result_fail("Failed to read %s SVE flags\n",
type->name);
return;
}
ksft_test_result(!(new_sve->flags & SVE_PT_VL_INHERIT),
"%s SVE_PT_VL_INHERIT cleared\n", type->name);
free(new_sve);
}
/* Validate attempting to set the specfied VL via ptrace */
static void ptrace_set_get_vl(pid_t child, const struct vec_type *type,
unsigned int vl, bool *supported)
{
struct user_sve_header sve;
struct user_sve_header *new_sve = NULL;
size_t new_sve_size = 0;
int ret, prctl_vl;
*supported = false;
/* Check if the VL is supported in this process */
prctl_vl = prctl(type->prctl_set, vl);
if (prctl_vl == -1)
ksft_exit_fail_msg("prctl(PR_%s_SET_VL) failed: %s (%d)\n",
type->name, strerror(errno), errno);
/* If the VL is not supported then a supported VL will be returned */
*supported = (prctl_vl == vl);
/* Set the VL by doing a set with no register payload */
memset(&sve, 0, sizeof(sve));
sve.size = sizeof(sve);
sve.vl = vl;
ret = set_sve(child, type, &sve);
if (ret != 0) {
ksft_test_result_fail("Failed to set %s VL %u\n",
type->name, vl);
return;
}
/*
* Read back the new register state and verify that we have the
* same VL that we got from prctl() on ourselves.
*/
if (!get_sve(child, type, (void **)&new_sve, &new_sve_size)) {
ksft_test_result_fail("Failed to read %s VL %u\n",
type->name, vl);
return;
}
ksft_test_result(new_sve->vl = prctl_vl, "Set %s VL %u\n",
type->name, vl);
free(new_sve);
}
static void check_u32(unsigned int vl, const char *reg,
uint32_t *in, uint32_t *out, int *errors)
{
if (*in != *out) {
printf("# VL %d %s wrote %x read %x\n",
vl, reg, *in, *out);
(*errors)++;
}
}
/* Access the FPSIMD registers via the SVE regset */
static void ptrace_sve_fpsimd(pid_t child, const struct vec_type *type)
{
void *svebuf;
struct user_sve_header *sve;
struct user_fpsimd_state *fpsimd, new_fpsimd;
unsigned int i, j;
unsigned char *p;
int ret;
svebuf = malloc(SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD));
if (!svebuf) {
ksft_test_result_fail("Failed to allocate FPSIMD buffer\n");
return;
}
memset(svebuf, 0, SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD));
sve = svebuf;
sve->flags = SVE_PT_REGS_FPSIMD;
sve->size = SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD);
sve->vl = 16; /* We don't care what the VL is */
/* Try to set a known FPSIMD state via PT_REGS_SVE */
fpsimd = (struct user_fpsimd_state *)((char *)sve +
SVE_PT_FPSIMD_OFFSET);
for (i = 0; i < 32; ++i) {
p = (unsigned char *)&fpsimd->vregs[i];
for (j = 0; j < sizeof(fpsimd->vregs[i]); ++j)
p[j] = j;
}
ret = set_sve(child, type, sve);
ksft_test_result(ret == 0, "%s FPSIMD set via SVE: %d\n",
type->name, ret);
if (ret)
goto out;
/* Verify via the FPSIMD regset */
if (get_fpsimd(child, &new_fpsimd)) {
ksft_test_result_fail("get_fpsimd(): %s\n",
strerror(errno));
goto out;
}
if (memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) == 0)
ksft_test_result_pass("%s get_fpsimd() gave same state\n",
type->name);
else
ksft_test_result_fail("%s get_fpsimd() gave different state\n",
type->name);
out:
free(svebuf);
}
/* Validate attempting to set SVE data and read SVE data */
static void ptrace_set_sve_get_sve_data(pid_t child,
const struct vec_type *type,
unsigned int vl)
{
void *write_buf;
void *read_buf = NULL;
struct user_sve_header *write_sve;
struct user_sve_header *read_sve;
size_t read_sve_size = 0;
unsigned int vq = sve_vq_from_vl(vl);
int ret, i;
size_t data_size;
int errors = 0;
data_size = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
write_buf = malloc(data_size);
if (!write_buf) {
ksft_test_result_fail("Error allocating %d byte buffer for %s VL %u\n",
data_size, type->name, vl);
return;
}
write_sve = write_buf;
/* Set up some data and write it out */
memset(write_sve, 0, data_size);
write_sve->size = data_size;
write_sve->vl = vl;
write_sve->flags = SVE_PT_REGS_SVE;
for (i = 0; i < __SVE_NUM_ZREGS; i++)
fill_buf(write_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
SVE_PT_SVE_ZREG_SIZE(vq));
for (i = 0; i < __SVE_NUM_PREGS; i++)
fill_buf(write_buf + SVE_PT_SVE_PREG_OFFSET(vq, i),
SVE_PT_SVE_PREG_SIZE(vq));
fill_buf(write_buf + SVE_PT_SVE_FPSR_OFFSET(vq), SVE_PT_SVE_FPSR_SIZE);
fill_buf(write_buf + SVE_PT_SVE_FPCR_OFFSET(vq), SVE_PT_SVE_FPCR_SIZE);
/* TODO: Generate a valid FFR pattern */
ret = set_sve(child, type, write_sve);
if (ret != 0) {
ksft_test_result_fail("Failed to set %s VL %u data\n",
type->name, vl);
goto out;
}
/* Read the data back */
if (!get_sve(child, type, (void **)&read_buf, &read_sve_size)) {
ksft_test_result_fail("Failed to read %s VL %u data\n",
type->name, vl);
goto out;
}
read_sve = read_buf;
/* We might read more data if there's extensions we don't know */
if (read_sve->size < write_sve->size) {
ksft_test_result_fail("%s wrote %d bytes, only read %d\n",
type->name, write_sve->size,
read_sve->size);
goto out_read;
}
for (i = 0; i < __SVE_NUM_ZREGS; i++) {
if (memcmp(write_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
read_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
SVE_PT_SVE_ZREG_SIZE(vq)) != 0) {
printf("# Mismatch in %u Z%d\n", vl, i);
errors++;
}
}
for (i = 0; i < __SVE_NUM_PREGS; i++) {
if (memcmp(write_buf + SVE_PT_SVE_PREG_OFFSET(vq, i),
read_buf + SVE_PT_SVE_PREG_OFFSET(vq, i),
SVE_PT_SVE_PREG_SIZE(vq)) != 0) {
printf("# Mismatch in %u P%d\n", vl, i);
errors++;
}
}
check_u32(vl, "FPSR", write_buf + SVE_PT_SVE_FPSR_OFFSET(vq),
read_buf + SVE_PT_SVE_FPSR_OFFSET(vq), &errors);
check_u32(vl, "FPCR", write_buf + SVE_PT_SVE_FPCR_OFFSET(vq),
read_buf + SVE_PT_SVE_FPCR_OFFSET(vq), &errors);
ksft_test_result(errors == 0, "Set and get %s data for VL %u\n",
type->name, vl);
out_read:
free(read_buf);
out:
free(write_buf);
}
/* Validate attempting to set SVE data and read it via the FPSIMD regset */
static void ptrace_set_sve_get_fpsimd_data(pid_t child,
const struct vec_type *type,
unsigned int vl)
{
void *write_buf;
struct user_sve_header *write_sve;
unsigned int vq = sve_vq_from_vl(vl);
struct user_fpsimd_state fpsimd_state;
int ret, i;
size_t data_size;
int errors = 0;
if (__BYTE_ORDER == __BIG_ENDIAN) {
ksft_test_result_skip("Big endian not supported\n");
return;
}
data_size = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
write_buf = malloc(data_size);
if (!write_buf) {
ksft_test_result_fail("Error allocating %d byte buffer for %s VL %u\n",
data_size, type->name, vl);
return;
}
write_sve = write_buf;
/* Set up some data and write it out */
memset(write_sve, 0, data_size);
write_sve->size = data_size;
write_sve->vl = vl;
write_sve->flags = SVE_PT_REGS_SVE;
for (i = 0; i < __SVE_NUM_ZREGS; i++)
fill_buf(write_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
SVE_PT_SVE_ZREG_SIZE(vq));
fill_buf(write_buf + SVE_PT_SVE_FPSR_OFFSET(vq), SVE_PT_SVE_FPSR_SIZE);
fill_buf(write_buf + SVE_PT_SVE_FPCR_OFFSET(vq), SVE_PT_SVE_FPCR_SIZE);
ret = set_sve(child, type, write_sve);
if (ret != 0) {
ksft_test_result_fail("Failed to set %s VL %u data\n",
type->name, vl);
goto out;
}
/* Read the data back */
if (get_fpsimd(child, &fpsimd_state)) {
ksft_test_result_fail("Failed to read %s VL %u FPSIMD data\n",
type->name, vl);
goto out;
}
for (i = 0; i < __SVE_NUM_ZREGS; i++) {
__uint128_t tmp = 0;
/*
* Z regs are stored endianness invariant, this won't
* work for big endian
*/
memcpy(&tmp, write_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
sizeof(tmp));
if (tmp != fpsimd_state.vregs[i]) {
printf("# Mismatch in FPSIMD for %s VL %u Z%d\n",
type->name, vl, i);
errors++;
}
}
check_u32(vl, "FPSR", write_buf + SVE_PT_SVE_FPSR_OFFSET(vq),
&fpsimd_state.fpsr, &errors);
check_u32(vl, "FPCR", write_buf + SVE_PT_SVE_FPCR_OFFSET(vq),
&fpsimd_state.fpcr, &errors);
ksft_test_result(errors == 0, "Set and get FPSIMD data for %s VL %u\n",
type->name, vl);
out:
free(write_buf);
}
/* Validate attempting to set FPSIMD data and read it via the SVE regset */
static void ptrace_set_fpsimd_get_sve_data(pid_t child,
const struct vec_type *type,
unsigned int vl)
{
void *read_buf = NULL;
unsigned char *p;
struct user_sve_header *read_sve;
unsigned int vq = sve_vq_from_vl(vl);
struct user_fpsimd_state write_fpsimd;
int ret, i, j;
size_t read_sve_size = 0;
size_t expected_size;
int errors = 0;
if (__BYTE_ORDER == __BIG_ENDIAN) {
ksft_test_result_skip("Big endian not supported\n");
return;
}
for (i = 0; i < 32; ++i) {
p = (unsigned char *)&write_fpsimd.vregs[i];
for (j = 0; j < sizeof(write_fpsimd.vregs[i]); ++j)
p[j] = j;
}
ret = set_fpsimd(child, &write_fpsimd);
if (ret != 0) {
ksft_test_result_fail("Failed to set FPSIMD state: %d\n)",
ret);
return;
}
if (!get_sve(child, type, (void **)&read_buf, &read_sve_size)) {
ksft_test_result_fail("Failed to read %s VL %u data\n",
type->name, vl);
return;
}
read_sve = read_buf;
if (read_sve->vl != vl) {
ksft_test_result_fail("Child VL != expected VL %d\n",
read_sve->vl, vl);
goto out;
}
/* The kernel may return either SVE or FPSIMD format */
switch (read_sve->flags & SVE_PT_REGS_MASK) {
case SVE_PT_REGS_FPSIMD:
expected_size = SVE_PT_FPSIMD_SIZE(vq, SVE_PT_REGS_FPSIMD);
if (read_sve_size < expected_size) {
ksft_test_result_fail("Read %d bytes, expected %d\n",
read_sve_size, expected_size);
goto out;
}
ret = memcmp(&write_fpsimd, read_buf + SVE_PT_FPSIMD_OFFSET,
sizeof(write_fpsimd));
if (ret != 0) {
ksft_print_msg("Read FPSIMD data mismatch\n");
errors++;
}
break;
case SVE_PT_REGS_SVE:
expected_size = SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
if (read_sve_size < expected_size) {
ksft_test_result_fail("Read %d bytes, expected %d\n",
read_sve_size, expected_size);
goto out;
}
for (i = 0; i < __SVE_NUM_ZREGS; i++) {
__uint128_t tmp = 0;
/*
* Z regs are stored endianness invariant, this won't
* work for big endian
*/
memcpy(&tmp, read_buf + SVE_PT_SVE_ZREG_OFFSET(vq, i),
sizeof(tmp));
if (tmp != write_fpsimd.vregs[i]) {
ksft_print_msg("Mismatch in FPSIMD for %s VL %u Z%d/V%d\n",
type->name, vl, i, i);
errors++;
}
}
check_u32(vl, "FPSR", &write_fpsimd.fpsr,
read_buf + SVE_PT_SVE_FPSR_OFFSET(vq), &errors);
check_u32(vl, "FPCR", &write_fpsimd.fpcr,
read_buf + SVE_PT_SVE_FPCR_OFFSET(vq), &errors);
break;
default:
ksft_print_msg("Unexpected regs type %d\n",
read_sve->flags & SVE_PT_REGS_MASK);
errors++;
break;
}
ksft_test_result(errors == 0, "Set FPSIMD, read via SVE for %s VL %u\n",
type->name, vl);
out:
free(read_buf);
}
static int do_parent(pid_t child)
{
int ret = EXIT_FAILURE;
pid_t pid;
int status, i;
siginfo_t si;
unsigned int vq, vl;
bool vl_supported;
ksft_print_msg("Parent is %d, child is %d\n", getpid(), child);
/* Attach to the child */
while (1) {
int sig;
pid = wait(&status);
if (pid == -1) {
perror("wait");
goto error;
}
/*
* This should never happen but it's hard to flag in
* the framework.
*/
if (pid != child)
continue;
if (WIFEXITED(status) || WIFSIGNALED(status))
ksft_exit_fail_msg("Child died unexpectedly\n");
if (!WIFSTOPPED(status))
goto error;
sig = WSTOPSIG(status);
if (ptrace(PTRACE_GETSIGINFO, pid, NULL, &si)) {
if (errno == ESRCH)
goto disappeared;
if (errno == EINVAL) {
sig = 0; /* bust group-stop */
goto cont;
}
ksft_test_result_fail("PTRACE_GETSIGINFO: %s\n",
strerror(errno));
goto error;
}
if (sig == SIGSTOP && si.si_code == SI_TKILL &&
si.si_pid == pid)
break;
cont:
if (ptrace(PTRACE_CONT, pid, NULL, sig)) {
if (errno == ESRCH)
goto disappeared;
ksft_test_result_fail("PTRACE_CONT: %s\n",
strerror(errno));
goto error;
}
}
for (i = 0; i < ARRAY_SIZE(vec_types); i++) {
/* FPSIMD via SVE regset */
if (getauxval(vec_types[i].hwcap_type) & vec_types[i].hwcap) {
ptrace_sve_fpsimd(child, &vec_types[i]);
} else {
ksft_test_result_skip("%s FPSIMD set via SVE\n",
vec_types[i].name);
ksft_test_result_skip("%s FPSIMD read\n",
vec_types[i].name);
}
/* prctl() flags */
if (getauxval(vec_types[i].hwcap_type) & vec_types[i].hwcap) {
ptrace_set_get_inherit(child, &vec_types[i]);
} else {
ksft_test_result_skip("%s SVE_PT_VL_INHERIT set\n",
vec_types[i].name);
ksft_test_result_skip("%s SVE_PT_VL_INHERIT cleared\n",
vec_types[i].name);
}
/* Step through every possible VQ */
for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; vq++) {
vl = sve_vl_from_vq(vq);
/* First, try to set this vector length */
if (getauxval(vec_types[i].hwcap_type) &
vec_types[i].hwcap) {
ptrace_set_get_vl(child, &vec_types[i], vl,
&vl_supported);
} else {
ksft_test_result_skip("%s get/set VL %d\n",
vec_types[i].name, vl);
vl_supported = false;
}
/* If the VL is supported validate data set/get */
if (vl_supported) {
ptrace_set_sve_get_sve_data(child, &vec_types[i], vl);
ptrace_set_sve_get_fpsimd_data(child, &vec_types[i], vl);
ptrace_set_fpsimd_get_sve_data(child, &vec_types[i], vl);
} else {
ksft_test_result_skip("%s set SVE get SVE for VL %d\n",
vec_types[i].name, vl);
ksft_test_result_skip("%s set SVE get FPSIMD for VL %d\n",
vec_types[i].name, vl);
ksft_test_result_skip("%s set FPSIMD get SVE for VL %d\n",
vec_types[i].name, vl);
}
}
}
ret = EXIT_SUCCESS;
error:
kill(child, SIGKILL);
disappeared:
return ret;
}
int main(void)
{
int ret = EXIT_SUCCESS;
pid_t child;
srandom(getpid());
ksft_print_header();
ksft_set_plan(EXPECTED_TESTS);
if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
ksft_exit_skip("SVE not available\n");
child = fork();
if (!child)
return do_child();
if (do_parent(child))
ret = EXIT_FAILURE;
ksft_print_cnts();
return ret;
}