diff options
Diffstat (limited to 'tools/testing/selftests/arm64/abi/ptrace.c')
-rw-r--r-- | tools/testing/selftests/arm64/abi/ptrace.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/tools/testing/selftests/arm64/abi/ptrace.c b/tools/testing/selftests/arm64/abi/ptrace.c new file mode 100644 index 0000000000..abe4d58d73 --- /dev/null +++ b/tools/testing/selftests/arm64/abi/ptrace.c @@ -0,0 +1,271 @@ +// 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]++; + 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"); + } +} + +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; +} |