@@ -8,4 +8,5 @@ sve-test
ssve-test
vec-syscfg
vlset
+za-ptrace
za-test
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
CFLAGS += -I../../../../../usr/include/
-TEST_GEN_PROGS := sve-ptrace sve-probe-vls vec-syscfg
+TEST_GEN_PROGS := sve-ptrace sve-probe-vls vec-syscfg za-ptrace
TEST_PROGS_EXTENDED := fp-pidbench fpsimd-test fpsimd-stress \
rdvl-sme rdvl-sve \
sve-test sve-stress \
@@ -27,5 +27,6 @@ vec-syscfg: vec-syscfg.o rdvl.o
vlset: vlset.o
za-test: za-test.o asm-utils.o
$(CC) -nostdlib $^ -o $@
+za-ptrace: za-ptrace.o
include ../../lib.mk
new file mode 100644
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 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"
+
+/* <linux/elf.h> and <sys/auxv.h> don't like each other, so: */
+#ifndef NT_ARM_ZA
+#define NT_ARM_ZA 0x40c
+#endif
+
+#define EXPECTED_TESTS (((SVE_VQ_MAX - SVE_VQ_MIN) + 1) * 3)
+
+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 struct user_za_header *get_za(pid_t pid, void **buf, size_t *size)
+{
+ struct user_za_header *za;
+ void *p;
+ size_t sz = sizeof(*za);
+ 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, NT_ARM_ZA, &iov))
+ goto error;
+
+ za = *buf;
+ if (za->size <= sz)
+ break;
+
+ sz = za->size;
+ }
+
+ return za;
+
+error:
+ return NULL;
+}
+
+static int set_za(pid_t pid, const struct user_za_header *za)
+{
+ struct iovec iov;
+
+ iov.iov_base = (void *)za;
+ iov.iov_len = za->size;
+ return ptrace(PTRACE_SETREGSET, pid, NT_ARM_ZA, &iov);
+}
+
+/* Validate attempting to set the specfied VL via ptrace */
+static void ptrace_set_get_vl(pid_t child, unsigned int vl, bool *supported)
+{
+ struct user_za_header za;
+ struct user_za_header *new_za = NULL;
+ size_t new_za_size = 0;
+ int ret, prctl_vl;
+
+ *supported = false;
+
+ /* Check if the VL is supported in this process */
+ prctl_vl = prctl(PR_SME_SET_VL, vl);
+ if (prctl_vl == -1)
+ ksft_exit_fail_msg("prctl(PR_SME_SET_VL) failed: %s (%d)\n",
+ 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(&za, 0, sizeof(za));
+ za.size = sizeof(za);
+ za.vl = vl;
+ ret = set_za(child, &za);
+ if (ret != 0) {
+ ksft_test_result_fail("Failed to set VL %u\n", 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_za(child, (void **)&new_za, &new_za_size)) {
+ ksft_test_result_fail("Failed to read VL %u\n", vl);
+ return;
+ }
+
+ ksft_test_result(new_za->vl = prctl_vl, "Set VL %u\n", vl);
+
+ free(new_za);
+}
+
+/* Validate attempting to set no ZA data and read it back */
+static void ptrace_set_no_data(pid_t child, unsigned int vl)
+{
+ void *read_buf = NULL;
+ struct user_za_header write_za;
+ struct user_za_header *read_za;
+ size_t read_za_size = 0;
+ int ret;
+
+ /* Set up some data and write it out */
+ memset(&write_za, 0, sizeof(write_za));
+ write_za.size = ZA_PT_ZA_OFFSET;
+ write_za.vl = vl;
+
+ ret = set_za(child, &write_za);
+ if (ret != 0) {
+ ksft_test_result_fail("Failed to set VL %u no data\n", vl);
+ return;
+ }
+
+ /* Read the data back */
+ if (!get_za(child, (void **)&read_buf, &read_za_size)) {
+ ksft_test_result_fail("Failed to read VL %u no data\n", vl);
+ return;
+ }
+ read_za = read_buf;
+
+ /* We might read more data if there's extensions we don't know */
+ if (read_za->size < write_za.size) {
+ ksft_test_result_fail("VL %u wrote %d bytes, only read %d\n",
+ vl, write_za.size, read_za->size);
+ goto out_read;
+ }
+
+ ksft_test_result(read_za->size == write_za.size,
+ "Disabled ZA for VL %u\n", vl);
+
+out_read:
+ free(read_buf);
+}
+
+/* Validate attempting to set data and read it back */
+static void ptrace_set_get_data(pid_t child, unsigned int vl)
+{
+ void *write_buf;
+ void *read_buf = NULL;
+ struct user_za_header *write_za;
+ struct user_za_header *read_za;
+ size_t read_za_size = 0;
+ unsigned int vq = sve_vq_from_vl(vl);
+ int ret;
+ size_t data_size;
+
+ data_size = ZA_PT_SIZE(vq);
+ write_buf = malloc(data_size);
+ if (!write_buf) {
+ ksft_test_result_fail("Error allocating %d byte buffer for VL %u\n",
+ data_size, vl);
+ return;
+ }
+ write_za = write_buf;
+
+ /* Set up some data and write it out */
+ memset(write_za, 0, data_size);
+ write_za->size = data_size;
+ write_za->vl = vl;
+
+ fill_buf(write_buf + ZA_PT_ZA_OFFSET, ZA_PT_ZA_SIZE(vq));
+
+ ret = set_za(child, write_za);
+ if (ret != 0) {
+ ksft_test_result_fail("Failed to set VL %u data\n", vl);
+ goto out;
+ }
+
+ /* Read the data back */
+ if (!get_za(child, (void **)&read_buf, &read_za_size)) {
+ ksft_test_result_fail("Failed to read VL %u data\n", vl);
+ goto out;
+ }
+ read_za = read_buf;
+
+ /* We might read more data if there's extensions we don't know */
+ if (read_za->size < write_za->size) {
+ ksft_test_result_fail("VL %u wrote %d bytes, only read %d\n",
+ vl, write_za->size, read_za->size);
+ goto out_read;
+ }
+
+ ksft_test_result(memcmp(write_buf + ZA_PT_ZA_OFFSET,
+ read_buf + ZA_PT_ZA_OFFSET,
+ ZA_PT_ZA_SIZE(vq)) == 0,
+ "Data match for VL %u\n", vl);
+
+out_read:
+ free(read_buf);
+out:
+ free(write_buf);
+}
+
+static int do_parent(pid_t child)
+{
+ int ret = EXIT_FAILURE;
+ pid_t pid;
+ int status;
+ siginfo_t si;
+ unsigned int vq, vl;
+ bool vl_supported;
+
+ /* 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);
+
+ /* 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 */
+ ptrace_set_get_vl(child, vl, &vl_supported);
+
+ /* If the VL is supported validate data set/get */
+ if (vl_supported) {
+ ptrace_set_no_data(child, vl);
+ ptrace_set_get_data(child, vl);
+ } else {
+ ksft_test_result_skip("Disabled ZA for VL %u\n", vl);
+ ksft_test_result_skip("Get and set data for VL %u\n",
+ 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();
+
+ if (!(getauxval(AT_HWCAP2) & HWCAP2_SME)) {
+ ksft_set_plan(1);
+ ksft_exit_skip("SME not available\n");
+ }
+
+ ksft_set_plan(EXPECTED_TESTS);
+
+ child = fork();
+ if (!child)
+ return do_child();
+
+ if (do_parent(child))
+ ret = EXIT_FAILURE;
+
+ ksft_print_cnts();
+
+ return ret;
+}