// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2022 ARM Limited.
*/
#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"
#define EXPECTED_TESTS 11
#define MAX_TPIDRS 2
static bool have_sme(void)
{
return getauxval(AT_HWCAP2) & HWCAP2_SME;
}
static void test_tpidr(pid_t child)
{
uint64_t read_val[MAX_TPIDRS];
uint64_t write_val[MAX_TPIDRS];
struct iovec read_iov, write_iov;
bool test_tpidr2 = false;
int ret, i;
read_iov.iov_base = read_val;
write_iov.iov_base = write_val;
/* Should be able to read a single TPIDR... */
read_iov.iov_len = sizeof(uint64_t);
ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_TLS, &read_iov);
ksft_test_result(ret == 0, "read_tpidr_one\n");
/* ...write a new value.. */
write_iov.iov_len = sizeof(uint64_t);
write_val[0] = read_val[0] + 1;
ret = ptrace(PTRACE_SETREGSET, child, NT_ARM_TLS, &write_iov);
ksft_test_result(ret == 0, "write_tpidr_one\n");
/* ...then read it back */
ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_TLS, &read_iov);
ksft_test_result(ret == 0 && write_val[0] == read_val[0],
"verify_tpidr_one\n");
/* If we have TPIDR2 we should be able to read it */
read_iov.iov_len = sizeof(read_val);
ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_TLS, &read_iov);
if (ret == 0) {
/* If we have SME there should be two TPIDRs */
if (read_iov.iov_len >= sizeof(read_val))
test_tpidr2 = true;
if (have_sme() && test_tpidr2) {
ksft_test_result(test_tpidr2, "count_tpidrs\n");
} else {
ksft_test_result(read_iov.iov_len % sizeof(uint64_t) == 0,
"count_tpidrs\n");
}
} else {
ksft_test_result_fail("count_tpidrs\n");
}
if (test_tpidr2) {
/* Try to write new values to all known TPIDRs... */
write_iov.iov_len = sizeof(write_val);
for (i = 0; i < MAX_TPIDRS; i++)
write_val[i] = read_val[i] + 1;
ret = ptrace(PTRACE_SETREGSET, child, NT_ARM_TLS, &write_iov);
ksft_test_result(ret == 0 &&
write_iov.iov_len == sizeof(write_val),
"tpidr2_write\n");
/* ...then read them back */
read_iov.iov_len = sizeof(read_val);
ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_TLS, &read_iov);
if (have_sme()) {
/* Should read back the written value */
ksft_test_result(ret == 0 &&
read_iov.iov_len >= sizeof(read_val) &&
memcmp(read_val, write_val,
sizeof(read_val)) == 0,
"tpidr2_read\n");
} else {
/* TPIDR2 should read as zero */
ksft_test_result(ret == 0 &&
read_iov.iov_len >= sizeof(read_val) &&
read_val[0] == write_val[0] &&
read_val[1] == 0,
"tpidr2_read\n");
}
/* Writing only TPIDR... */
write_iov.iov_len = sizeof(uint64_t);
memcpy(write_val, read_val, sizeof(read_val));
write_val[0] += 1;
ret = ptrace(PTRACE_SETREGSET, child, NT_ARM_TLS, &write_iov);
if (ret == 0) {
/* ...should leave TPIDR2 untouched */
read_iov.iov_len = sizeof(read_val);
ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_TLS,
&read_iov);
ksft_test_result(ret == 0 &&
read_iov.iov_len >= sizeof(read_val) &&
memcmp(read_val, write_val,
sizeof(read_val)) == 0,
"write_tpidr_only\n");
} else {
ksft_test_result_fail("write_tpidr_only\n");
}
} else {
ksft_test_result_skip("tpidr2_write\n");
ksft_test_result_skip("tpidr2_read\n");
ksft_test_result_skip("write_tpidr_only\n");
}
}
static void test_hw_debug(pid_t child, int type, const char *type_name)
{
struct user_hwdebug_state state;
struct iovec iov;
int slots, arch, ret;
iov.iov_len = sizeof(state);
iov.iov_base = &state;
/* Should be able to read the values */
ret = ptrace(PTRACE_GETREGSET, child, type, &iov);
ksft_test_result(ret == 0, "read_%s\n", type_name);
if (ret == 0) {
/* Low 8 bits is the number of slots, next 4 bits the arch */
slots = state.dbg_info & 0xff;
arch = (state.dbg_info >> 8) & 0xf;
ksft_print_msg("%s version %d with %d slots\n", type_name,
arch, slots);
/* Zero is not currently architecturally valid */
ksft_test_result(arch, "%s_arch_set\n", type_name);
} else {
ksft_test_result_skip("%s_arch_set\n", type_name);
}
}
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 do_parent(pid_t child)
{
int ret = EXIT_FAILURE;
pid_t pid;
int status;
siginfo_t si;
/* 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;
}
}
ksft_print_msg("Parent is %d, child is %d\n", getpid(), child);
test_tpidr(child);
test_hw_debug(child, NT_ARM_HW_WATCH, "NT_ARM_HW_WATCH");
test_hw_debug(child, NT_ARM_HW_BREAK, "NT_ARM_HW_BREAK");
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);
child = fork();
if (!child)
return do_child();
if (do_parent(child))
ret = EXIT_FAILURE;
ksft_print_cnts();
return ret;
}
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