@@ -1,2 +1,3 @@
+ptrace
syscall-abi
tpidr2
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2021 ARM Limited
-TEST_GEN_PROGS := syscall-abi tpidr2
+TEST_GEN_PROGS := ptrace syscall-abi tpidr2
include ../../lib.mk
new file mode 100644
@@ -0,0 +1,165 @@
+// 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 3
+
+#define MAX_TPIDRS 1
+
+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;
+ int ret;
+
+ 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]++;
+ 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");
+}
+
+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);
+
+ 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;
+}
In preparation for extending support for NT_ARM_TLS to cover additional TPIDRs add some tests for the existing interface. Do this in a generic ptrace test program to provide a place to collect additional tests in the future. Signed-off-by: Mark Brown <broonie@kernel.org> --- tools/testing/selftests/arm64/abi/.gitignore | 1 + tools/testing/selftests/arm64/abi/Makefile | 2 +- tools/testing/selftests/arm64/abi/ptrace.c | 165 +++++++++++++++++++ 3 files changed, 167 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/abi/ptrace.c