Adding upstream version 6.9.2.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 1800 insertions, 1 deletions

diff --git a/tools/testing/selftests/arm64/fp/.gitignore b/tools/testing/selftests/arm64/fp/.gitignore
index ebc86757bd..00e52c9662 100644
--- a/tools/testing/selftests/arm64/fp/.gitignore
+++ b/tools/testing/selftests/arm64/fp/.gitignore
@@ -1,4 +1,5 @@
 fp-pidbench
+fp-ptrace
 fp-stress
 fpsimd-test
 rdvl-sme
diff --git a/tools/testing/selftests/arm64/fp/Makefile b/tools/testing/selftests/arm64/fp/Makefile
index b413b0af07..55d4f00d9e 100644
--- a/tools/testing/selftests/arm64/fp/Makefile
+++ b/tools/testing/selftests/arm64/fp/Makefile
@@ -5,7 +5,9 @@ top_srcdir = $(realpath ../../../../../)
 
 CFLAGS += $(KHDR_INCLUDES)
 
-TEST_GEN_PROGS := fp-stress \
+TEST_GEN_PROGS := \
+	fp-ptrace \
+	fp-stress \
 	sve-ptrace sve-probe-vls \
 	vec-syscfg \
 	za-fork za-ptrace
@@ -24,6 +26,7 @@ EXTRA_CLEAN += $(OUTPUT)/asm-utils.o $(OUTPUT)/rdvl.o $(OUTPUT)/za-fork-asm.o
 # Build with nolibc to avoid effects due to libc's clone() support
 $(OUTPUT)/fp-pidbench: fp-pidbench.S $(OUTPUT)/asm-utils.o
 	$(CC) -nostdlib $^ -o $@
+$(OUTPUT)/fp-ptrace: fp-ptrace.c fp-ptrace-asm.S
 $(OUTPUT)/fpsimd-test: fpsimd-test.S $(OUTPUT)/asm-utils.o
 	$(CC) -nostdlib $^ -o $@
 $(OUTPUT)/rdvl-sve: rdvl-sve.c $(OUTPUT)/rdvl.o
diff --git a/tools/testing/selftests/arm64/fp/fp-ptrace-asm.S b/tools/testing/selftests/arm64/fp/fp-ptrace-asm.S
new file mode 100644
index 0000000000..7ad59d92d0
--- /dev/null
+++ b/tools/testing/selftests/arm64/fp/fp-ptrace-asm.S
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2021-3 ARM Limited.
+//
+// Assembly portion of the FP ptrace test
+
+//
+// Load values from memory into registers, break on a breakpoint, then
+// break on a further breakpoint
+//
+
+#include "fp-ptrace.h"
+#include "sme-inst.h"
+
+.arch_extension sve
+
+// Load and save register values with pauses for ptrace
+//
+// x0 - SVE in use
+// x1 - SME in use
+// x2 - SME2 in use
+// x3 - FA64 supported
+
+.globl load_and_save
+load_and_save:
+	stp	x11, x12, [sp, #-0x10]!
+
+	// This should be redundant in the SVE case
+	ldr	x7, =v_in
+	ldp	q0, q1, [x7]
+	ldp	q2, q3, [x7, #16 * 2]
+	ldp	q4, q5, [x7, #16 * 4]
+	ldp	q6, q7, [x7, #16 * 6]
+	ldp	q8, q9, [x7, #16 * 8]
+	ldp	q10, q11, [x7, #16 * 10]
+	ldp	q12, q13, [x7, #16 * 12]
+	ldp	q14, q15, [x7, #16 * 14]
+	ldp	q16, q17, [x7, #16 * 16]
+	ldp	q18, q19, [x7, #16 * 18]
+	ldp	q20, q21, [x7, #16 * 20]
+	ldp	q22, q23, [x7, #16 * 22]
+	ldp	q24, q25, [x7, #16 * 24]
+	ldp	q26, q27, [x7, #16 * 26]
+	ldp	q28, q29, [x7, #16 * 28]
+	ldp	q30, q31, [x7, #16 * 30]
+
+	// SME?
+	cbz	x1, check_sve_in
+
+	adrp	x7, svcr_in
+	ldr	x7, [x7, :lo12:svcr_in]
+	// SVCR is 0 by default, avoid triggering SME if not in use
+	cbz	x7, check_sve_in
+	msr	S3_3_C4_C2_2, x7
+
+	// ZA?
+	tbz	x7, #SVCR_ZA_SHIFT, check_sm_in
+	rdsvl	11, 1
+	mov	w12, #0
+	ldr	x6, =za_in
+1:	_ldr_za 12, 6
+	add	x6, x6, x11
+	add	x12, x12, #1
+	cmp	x11, x12
+	bne	1b
+
+	// ZT?
+	cbz	x2, check_sm_in
+	adrp	x6, zt_in
+	add	x6, x6, :lo12:zt_in
+	_ldr_zt 6
+
+	// In streaming mode?
+check_sm_in:
+	tbz	x7, #SVCR_SM_SHIFT, check_sve_in
+	mov	x4, x3		// Load FFR if we have FA64
+	b	load_sve
+
+	// SVE?
+check_sve_in:
+	cbz	x0, wait_for_writes
+	mov	x4, #1
+
+load_sve:
+	ldr	x7, =z_in
+	ldr	z0, [x7, #0, MUL VL]
+	ldr	z1, [x7, #1, MUL VL]
+	ldr	z2, [x7, #2, MUL VL]
+	ldr	z3, [x7, #3, MUL VL]
+	ldr	z4, [x7, #4, MUL VL]
+	ldr	z5, [x7, #5, MUL VL]
+	ldr	z6, [x7, #6, MUL VL]
+	ldr	z7, [x7, #7, MUL VL]
+	ldr	z8, [x7, #8, MUL VL]
+	ldr	z9, [x7, #9, MUL VL]
+	ldr	z10, [x7, #10, MUL VL]
+	ldr	z11, [x7, #11, MUL VL]
+	ldr	z12, [x7, #12, MUL VL]
+	ldr	z13, [x7, #13, MUL VL]
+	ldr	z14, [x7, #14, MUL VL]
+	ldr	z15, [x7, #15, MUL VL]
+	ldr	z16, [x7, #16, MUL VL]
+	ldr	z17, [x7, #17, MUL VL]
+	ldr	z18, [x7, #18, MUL VL]
+	ldr	z19, [x7, #19, MUL VL]
+	ldr	z20, [x7, #20, MUL VL]
+	ldr	z21, [x7, #21, MUL VL]
+	ldr	z22, [x7, #22, MUL VL]
+	ldr	z23, [x7, #23, MUL VL]
+	ldr	z24, [x7, #24, MUL VL]
+	ldr	z25, [x7, #25, MUL VL]
+	ldr	z26, [x7, #26, MUL VL]
+	ldr	z27, [x7, #27, MUL VL]
+	ldr	z28, [x7, #28, MUL VL]
+	ldr	z29, [x7, #29, MUL VL]
+	ldr	z30, [x7, #30, MUL VL]
+	ldr	z31, [x7, #31, MUL VL]
+
+	// FFR is not present in base SME
+	cbz	x4, 1f
+	ldr	x7, =ffr_in
+	ldr	p0, [x7]
+	ldr	x7, [x7, #0]
+	cbz	x7, 1f
+	wrffr	p0.b
+1:
+
+	ldr	x7, =p_in
+	ldr	p0, [x7, #0, MUL VL]
+	ldr	p1, [x7, #1, MUL VL]
+	ldr	p2, [x7, #2, MUL VL]
+	ldr	p3, [x7, #3, MUL VL]
+	ldr	p4, [x7, #4, MUL VL]
+	ldr	p5, [x7, #5, MUL VL]
+	ldr	p6, [x7, #6, MUL VL]
+	ldr	p7, [x7, #7, MUL VL]
+	ldr	p8, [x7, #8, MUL VL]
+	ldr	p9, [x7, #9, MUL VL]
+	ldr	p10, [x7, #10, MUL VL]
+	ldr	p11, [x7, #11, MUL VL]
+	ldr	p12, [x7, #12, MUL VL]
+	ldr	p13, [x7, #13, MUL VL]
+	ldr	p14, [x7, #14, MUL VL]
+	ldr	p15, [x7, #15, MUL VL]
+
+wait_for_writes:
+	// Wait for the parent
+	brk #0
+
+	// Save values
+	ldr	x7, =v_out
+	stp	q0, q1, [x7]
+	stp	q2, q3, [x7, #16 * 2]
+	stp	q4, q5, [x7, #16 * 4]
+	stp	q6, q7, [x7, #16 * 6]
+	stp	q8, q9, [x7, #16 * 8]
+	stp	q10, q11, [x7, #16 * 10]
+	stp	q12, q13, [x7, #16 * 12]
+	stp	q14, q15, [x7, #16 * 14]
+	stp	q16, q17, [x7, #16 * 16]
+	stp	q18, q19, [x7, #16 * 18]
+	stp	q20, q21, [x7, #16 * 20]
+	stp	q22, q23, [x7, #16 * 22]
+	stp	q24, q25, [x7, #16 * 24]
+	stp	q26, q27, [x7, #16 * 26]
+	stp	q28, q29, [x7, #16 * 28]
+	stp	q30, q31, [x7, #16 * 30]
+
+	// SME?
+	cbz	x1, check_sve_out
+
+	rdsvl	11, 1
+	adrp	x6, sme_vl_out
+	str	x11, [x6, :lo12:sme_vl_out]
+
+	mrs	x7, S3_3_C4_C2_2
+	adrp	x6, svcr_out
+	str	x7, [x6, :lo12:svcr_out]
+
+	// ZA?
+	tbz	x7, #SVCR_ZA_SHIFT, check_sm_out
+	mov	w12, #0
+	ldr	x6, =za_out
+1:	_str_za 12, 6
+	add	x6, x6, x11
+	add	x12, x12, #1
+	cmp	x11, x12
+	bne	1b
+
+	// ZT?
+	cbz	x2, check_sm_out
+	adrp	x6, zt_out
+	add	x6, x6, :lo12:zt_out
+	_str_zt 6
+
+	// In streaming mode?
+check_sm_out:
+	tbz	x7, #SVCR_SM_SHIFT, check_sve_out
+	mov	x4, x3				// FFR?
+	b	read_sve
+
+	// SVE?
+check_sve_out:
+	cbz	x0, wait_for_reads
+	mov	x4, #1
+
+	rdvl	x7, #1
+	adrp	x6, sve_vl_out
+	str	x7, [x6, :lo12:sve_vl_out]
+
+read_sve:
+	ldr	x7, =z_out
+	str	z0, [x7, #0, MUL VL]
+	str	z1, [x7, #1, MUL VL]
+	str	z2, [x7, #2, MUL VL]
+	str	z3, [x7, #3, MUL VL]
+	str	z4, [x7, #4, MUL VL]
+	str	z5, [x7, #5, MUL VL]
+	str	z6, [x7, #6, MUL VL]
+	str	z7, [x7, #7, MUL VL]
+	str	z8, [x7, #8, MUL VL]
+	str	z9, [x7, #9, MUL VL]
+	str	z10, [x7, #10, MUL VL]
+	str	z11, [x7, #11, MUL VL]
+	str	z12, [x7, #12, MUL VL]
+	str	z13, [x7, #13, MUL VL]
+	str	z14, [x7, #14, MUL VL]
+	str	z15, [x7, #15, MUL VL]
+	str	z16, [x7, #16, MUL VL]
+	str	z17, [x7, #17, MUL VL]
+	str	z18, [x7, #18, MUL VL]
+	str	z19, [x7, #19, MUL VL]
+	str	z20, [x7, #20, MUL VL]
+	str	z21, [x7, #21, MUL VL]
+	str	z22, [x7, #22, MUL VL]
+	str	z23, [x7, #23, MUL VL]
+	str	z24, [x7, #24, MUL VL]
+	str	z25, [x7, #25, MUL VL]
+	str	z26, [x7, #26, MUL VL]
+	str	z27, [x7, #27, MUL VL]
+	str	z28, [x7, #28, MUL VL]
+	str	z29, [x7, #29, MUL VL]
+	str	z30, [x7, #30, MUL VL]
+	str	z31, [x7, #31, MUL VL]
+
+	ldr	x7, =p_out
+	str	p0, [x7, #0, MUL VL]
+	str	p1, [x7, #1, MUL VL]
+	str	p2, [x7, #2, MUL VL]
+	str	p3, [x7, #3, MUL VL]
+	str	p4, [x7, #4, MUL VL]
+	str	p5, [x7, #5, MUL VL]
+	str	p6, [x7, #6, MUL VL]
+	str	p7, [x7, #7, MUL VL]
+	str	p8, [x7, #8, MUL VL]
+	str	p9, [x7, #9, MUL VL]
+	str	p10, [x7, #10, MUL VL]
+	str	p11, [x7, #11, MUL VL]
+	str	p12, [x7, #12, MUL VL]
+	str	p13, [x7, #13, MUL VL]
+	str	p14, [x7, #14, MUL VL]
+	str	p15, [x7, #15, MUL VL]
+
+	// Only save FFR if it exists
+	cbz	x4, wait_for_reads
+	ldr	x7, =ffr_out
+	rdffr	p0.b
+	str	p0, [x7]
+
+wait_for_reads:
+	// Wait for the parent
+	brk #0
+
+	// Ensure we don't leave ourselves in streaming mode
+	cbz	x1, out
+	msr	S3_3_C4_C2_2, xzr
+
+out:
+	ldp	x11, x12, [sp, #-0x10]
+	ret
diff --git a/tools/testing/selftests/arm64/fp/fp-ptrace.c b/tools/testing/selftests/arm64/fp/fp-ptrace.c
new file mode 100644
index 0000000000..c7ceafe5f4
--- /dev/null
+++ b/tools/testing/selftests/arm64/fp/fp-ptrace.c
@@ -0,0 +1,1503 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023 ARM Limited.
+ * Original author: Mark Brown <broonie@kernel.org>
+ */
+
+#define _GNU_SOURCE
+
+#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 <linux/kernel.h>
+
+#include <asm/sigcontext.h>
+#include <asm/sve_context.h>
+#include <asm/ptrace.h>
+
+#include "../../kselftest.h"
+
+#include "fp-ptrace.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
+
+#ifndef NT_ARM_ZA
+#define NT_ARM_ZA 0x40c
+#endif
+
+#ifndef NT_ARM_ZT
+#define NT_ARM_ZT 0x40d
+#endif
+
+#define ARCH_VQ_MAX 256
+
+/* VL 128..2048 in powers of 2 */
+#define MAX_NUM_VLS 5
+
+#define NUM_FPR 32
+__uint128_t v_in[NUM_FPR];
+__uint128_t v_expected[NUM_FPR];
+__uint128_t v_out[NUM_FPR];
+
+char z_in[__SVE_ZREGS_SIZE(ARCH_VQ_MAX)];
+char z_expected[__SVE_ZREGS_SIZE(ARCH_VQ_MAX)];
+char z_out[__SVE_ZREGS_SIZE(ARCH_VQ_MAX)];
+
+char p_in[__SVE_PREGS_SIZE(ARCH_VQ_MAX)];
+char p_expected[__SVE_PREGS_SIZE(ARCH_VQ_MAX)];
+char p_out[__SVE_PREGS_SIZE(ARCH_VQ_MAX)];
+
+char ffr_in[__SVE_PREG_SIZE(ARCH_VQ_MAX)];
+char ffr_expected[__SVE_PREG_SIZE(ARCH_VQ_MAX)];
+char ffr_out[__SVE_PREG_SIZE(ARCH_VQ_MAX)];
+
+char za_in[ZA_SIG_REGS_SIZE(ARCH_VQ_MAX)];
+char za_expected[ZA_SIG_REGS_SIZE(ARCH_VQ_MAX)];
+char za_out[ZA_SIG_REGS_SIZE(ARCH_VQ_MAX)];
+
+char zt_in[ZT_SIG_REG_BYTES];
+char zt_expected[ZT_SIG_REG_BYTES];
+char zt_out[ZT_SIG_REG_BYTES];
+
+uint64_t sve_vl_out;
+uint64_t sme_vl_out;
+uint64_t svcr_in, svcr_expected, svcr_out;
+
+void load_and_save(int sve, int sme, int sme2, int fa64);
+
+static bool got_alarm;
+
+static void handle_alarm(int sig, siginfo_t *info, void *context)
+{
+	got_alarm = true;
+}
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+static __uint128_t arm64_cpu_to_le128(__uint128_t x)
+{
+	u64 a = swab64(x);
+	u64 b = swab64(x >> 64);
+
+	return ((__uint128_t)a << 64) | b;
+}
+#else
+static __uint128_t arm64_cpu_to_le128(__uint128_t x)
+{
+	return x;
+}
+#endif
+
+#define arm64_le128_to_cpu(x) arm64_cpu_to_le128(x)
+
+static bool sve_supported(void)
+{
+	return getauxval(AT_HWCAP) & HWCAP_SVE;
+}
+
+static bool sme_supported(void)
+{
+	return getauxval(AT_HWCAP2) & HWCAP2_SME;
+}
+
+static bool sme2_supported(void)
+{
+	return getauxval(AT_HWCAP2) & HWCAP2_SME2;
+}
+
+static bool fa64_supported(void)
+{
+	return getauxval(AT_HWCAP2) & HWCAP2_SME_FA64;
+}
+
+static bool compare_buffer(const char *name, void *out,
+			   void *expected, size_t size)
+{
+	void *tmp;
+
+	if (memcmp(out, expected, size) == 0)
+		return true;
+
+	ksft_print_msg("Mismatch in %s\n", name);
+
+	/* Did we just get zeros back? */
+	tmp = malloc(size);
+	if (!tmp) {
+		ksft_print_msg("OOM allocating %lu bytes for %s\n",
+			       size, name);
+		ksft_exit_fail();
+	}
+	memset(tmp, 0, size);
+
+	if (memcmp(out, tmp, size) == 0)
+		ksft_print_msg("%s is zero\n", name);
+
+	free(tmp);
+
+	return false;
+}
+
+struct test_config {
+	int sve_vl_in;
+	int sve_vl_expected;
+	int sme_vl_in;
+	int sme_vl_expected;
+	int svcr_in;
+	int svcr_expected;
+};
+
+struct test_definition {
+	const char *name;
+	bool sve_vl_change;
+	bool (*supported)(struct test_config *config);
+	void (*set_expected_values)(struct test_config *config);
+	void (*modify_values)(pid_t child, struct test_config *test_config);
+};
+
+static int vl_in(struct test_config *config)
+{
+	int vl;
+
+	if (config->svcr_in & SVCR_SM)
+		vl = config->sme_vl_in;
+	else
+		vl = config->sve_vl_in;
+
+	return vl;
+}
+
+static int vl_expected(struct test_config *config)
+{
+	int vl;
+
+	if (config->svcr_expected & SVCR_SM)
+		vl = config->sme_vl_expected;
+	else
+		vl = config->sve_vl_expected;
+
+	return vl;
+}
+
+static void run_child(struct test_config *config)
+{
+	int ret;
+
+	/* Let the parent attach to us */
+	ret = ptrace(PTRACE_TRACEME, 0, 0, 0);
+	if (ret < 0)
+		ksft_exit_fail_msg("PTRACE_TRACEME failed: %s (%d)\n",
+				   strerror(errno), errno);
+
+	/* VL setup */
+	if (sve_supported()) {
+		ret = prctl(PR_SVE_SET_VL, config->sve_vl_in);
+		if (ret != config->sve_vl_in) {
+			ksft_print_msg("Failed to set SVE VL %d: %d\n",
+				       config->sve_vl_in, ret);
+		}
+	}
+
+	if (sme_supported()) {
+		ret = prctl(PR_SME_SET_VL, config->sme_vl_in);
+		if (ret != config->sme_vl_in) {
+			ksft_print_msg("Failed to set SME VL %d: %d\n",
+				       config->sme_vl_in, ret);
+		}
+	}
+
+	/* Load values and wait for the parent */
+	load_and_save(sve_supported(), sme_supported(),
+		      sme2_supported(), fa64_supported());
+
+	exit(0);
+}
+
+static void read_one_child_regs(pid_t child, char *name,
+				struct iovec *iov_parent,
+				struct iovec *iov_child)
+{
+	int len = iov_parent->iov_len;
+	int ret;
+
+	ret = process_vm_readv(child, iov_parent, 1, iov_child, 1, 0);
+	if (ret == -1)
+		ksft_print_msg("%s read failed: %s (%d)\n",
+			       name, strerror(errno), errno);
+	else if (ret != len)
+		ksft_print_msg("Short read of %s: %d\n", name, ret);
+}
+
+static void read_child_regs(pid_t child)
+{
+	struct iovec iov_parent, iov_child;
+
+	/*
+	 * Since the child fork()ed from us the buffer addresses are
+	 * the same in parent and child.
+	 */
+	iov_parent.iov_base = &v_out;
+	iov_parent.iov_len = sizeof(v_out);
+	iov_child.iov_base = &v_out;
+	iov_child.iov_len = sizeof(v_out);
+	read_one_child_regs(child, "FPSIMD", &iov_parent, &iov_child);
+
+	if (sve_supported() || sme_supported()) {
+		iov_parent.iov_base = &sve_vl_out;
+		iov_parent.iov_len = sizeof(sve_vl_out);
+		iov_child.iov_base = &sve_vl_out;
+		iov_child.iov_len = sizeof(sve_vl_out);
+		read_one_child_regs(child, "SVE VL", &iov_parent, &iov_child);
+
+		iov_parent.iov_base = &z_out;
+		iov_parent.iov_len = sizeof(z_out);
+		iov_child.iov_base = &z_out;
+		iov_child.iov_len = sizeof(z_out);
+		read_one_child_regs(child, "Z", &iov_parent, &iov_child);
+
+		iov_parent.iov_base = &p_out;
+		iov_parent.iov_len = sizeof(p_out);
+		iov_child.iov_base = &p_out;
+		iov_child.iov_len = sizeof(p_out);
+		read_one_child_regs(child, "P", &iov_parent, &iov_child);
+
+		iov_parent.iov_base = &ffr_out;
+		iov_parent.iov_len = sizeof(ffr_out);
+		iov_child.iov_base = &ffr_out;
+		iov_child.iov_len = sizeof(ffr_out);
+		read_one_child_regs(child, "FFR", &iov_parent, &iov_child);
+	}
+
+	if (sme_supported()) {
+		iov_parent.iov_base = &sme_vl_out;
+		iov_parent.iov_len = sizeof(sme_vl_out);
+		iov_child.iov_base = &sme_vl_out;
+		iov_child.iov_len = sizeof(sme_vl_out);
+		read_one_child_regs(child, "SME VL", &iov_parent, &iov_child);
+
+		iov_parent.iov_base = &svcr_out;
+		iov_parent.iov_len = sizeof(svcr_out);
+		iov_child.iov_base = &svcr_out;
+		iov_child.iov_len = sizeof(svcr_out);
+		read_one_child_regs(child, "SVCR", &iov_parent, &iov_child);
+
+		iov_parent.iov_base = &za_out;
+		iov_parent.iov_len = sizeof(za_out);
+		iov_child.iov_base = &za_out;
+		iov_child.iov_len = sizeof(za_out);
+		read_one_child_regs(child, "ZA", &iov_parent, &iov_child);
+	}
+
+	if (sme2_supported()) {
+		iov_parent.iov_base = &zt_out;
+		iov_parent.iov_len = sizeof(zt_out);
+		iov_child.iov_base = &zt_out;
+		iov_child.iov_len = sizeof(zt_out);
+		read_one_child_regs(child, "ZT", &iov_parent, &iov_child);
+	}
+}
+
+static bool continue_breakpoint(pid_t child,
+				enum __ptrace_request restart_type)
+{
+	struct user_pt_regs pt_regs;
+	struct iovec iov;
+	int ret;
+
+	/* Get PC */
+	iov.iov_base = &pt_regs;
+	iov.iov_len = sizeof(pt_regs);
+	ret = ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov);
+	if (ret < 0) {
+		ksft_print_msg("Failed to get PC: %s (%d)\n",
+			       strerror(errno), errno);
+		return false;
+	}
+
+	/* Skip over the BRK */
+	pt_regs.pc += 4;
+	ret = ptrace(PTRACE_SETREGSET, child, NT_PRSTATUS, &iov);
+	if (ret < 0) {
+		ksft_print_msg("Failed to skip BRK: %s (%d)\n",
+			       strerror(errno), errno);
+		return false;
+	}
+
+	/* Restart */
+	ret = ptrace(restart_type, child, 0, 0);
+	if (ret < 0) {
+		ksft_print_msg("Failed to restart child: %s (%d)\n",
+			       strerror(errno), errno);
+		return false;
+	}
+
+	return true;
+}
+
+static bool check_ptrace_values_sve(pid_t child, struct test_config *config)
+{
+	struct user_sve_header *sve;
+	struct user_fpsimd_state *fpsimd;
+	struct iovec iov;
+	int ret, vq;
+	bool pass = true;
+
+	if (!sve_supported())
+		return true;
+
+	vq = __sve_vq_from_vl(config->sve_vl_in);
+
+	iov.iov_len = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		ksft_print_msg("OOM allocating %lu byte SVE buffer\n",
+			       iov.iov_len);
+		return false;
+	}
+
+	ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_SVE, &iov);
+	if (ret != 0) {
+		ksft_print_msg("Failed to read initial SVE: %s (%d)\n",
+			       strerror(errno), errno);
+		pass = false;
+		goto out;
+	}
+
+	sve = iov.iov_base;
+
+	if (sve->vl != config->sve_vl_in) {
+		ksft_print_msg("Mismatch in initial SVE VL: %d != %d\n",
+			       sve->vl, config->sve_vl_in);
+		pass = false;
+	}
+
+	/* If we are in streaming mode we should just read FPSIMD */
+	if ((config->svcr_in & SVCR_SM) && (sve->flags & SVE_PT_REGS_SVE)) {
+		ksft_print_msg("NT_ARM_SVE reports SVE with PSTATE.SM\n");
+		pass = false;
+	}
+
+	if (sve->size != SVE_PT_SIZE(vq, sve->flags)) {
+		ksft_print_msg("Mismatch in SVE header size: %d != %lu\n",
+			       sve->size, SVE_PT_SIZE(vq, sve->flags));
+		pass = false;
+	}
+
+	/* The registers might be in completely different formats! */
+	if (sve->flags & SVE_PT_REGS_SVE) {
+		if (!compare_buffer("initial SVE Z",
+				    iov.iov_base + SVE_PT_SVE_ZREG_OFFSET(vq, 0),
+				    z_in, SVE_PT_SVE_ZREGS_SIZE(vq)))
+			pass = false;
+
+		if (!compare_buffer("initial SVE P",
+				    iov.iov_base + SVE_PT_SVE_PREG_OFFSET(vq, 0),
+				    p_in, SVE_PT_SVE_PREGS_SIZE(vq)))
+			pass = false;
+
+		if (!compare_buffer("initial SVE FFR",
+				    iov.iov_base + SVE_PT_SVE_FFR_OFFSET(vq),
+				    ffr_in, SVE_PT_SVE_PREG_SIZE(vq)))
+			pass = false;
+	} else {
+		fpsimd = iov.iov_base + SVE_PT_FPSIMD_OFFSET;
+		if (!compare_buffer("initial V via SVE", &fpsimd->vregs[0],
+				    v_in, sizeof(v_in)))
+			pass = false;
+	}
+
+out:
+	free(iov.iov_base);
+	return pass;
+}
+
+static bool check_ptrace_values_ssve(pid_t child, struct test_config *config)
+{
+	struct user_sve_header *sve;
+	struct user_fpsimd_state *fpsimd;
+	struct iovec iov;
+	int ret, vq;
+	bool pass = true;
+
+	if (!sme_supported())
+		return true;
+
+	vq = __sve_vq_from_vl(config->sme_vl_in);
+
+	iov.iov_len = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		ksft_print_msg("OOM allocating %lu byte SSVE buffer\n",
+			       iov.iov_len);
+		return false;
+	}
+
+	ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_SSVE, &iov);
+	if (ret != 0) {
+		ksft_print_msg("Failed to read initial SSVE: %s (%d)\n",
+			       strerror(errno), errno);
+		pass = false;
+		goto out;
+	}
+
+	sve = iov.iov_base;
+
+	if (sve->vl != config->sme_vl_in) {
+		ksft_print_msg("Mismatch in initial SSVE VL: %d != %d\n",
+			       sve->vl, config->sme_vl_in);
+		pass = false;
+	}
+
+	if ((config->svcr_in & SVCR_SM) && !(sve->flags & SVE_PT_REGS_SVE)) {
+		ksft_print_msg("NT_ARM_SSVE reports FPSIMD with PSTATE.SM\n");
+		pass = false;
+	}
+
+	if (sve->size != SVE_PT_SIZE(vq, sve->flags)) {
+		ksft_print_msg("Mismatch in SSVE header size: %d != %lu\n",
+			       sve->size, SVE_PT_SIZE(vq, sve->flags));
+		pass = false;
+	}
+
+	/* The registers might be in completely different formats! */
+	if (sve->flags & SVE_PT_REGS_SVE) {
+		if (!compare_buffer("initial SSVE Z",
+				    iov.iov_base + SVE_PT_SVE_ZREG_OFFSET(vq, 0),
+				    z_in, SVE_PT_SVE_ZREGS_SIZE(vq)))
+			pass = false;
+
+		if (!compare_buffer("initial SSVE P",
+				    iov.iov_base + SVE_PT_SVE_PREG_OFFSET(vq, 0),
+				    p_in, SVE_PT_SVE_PREGS_SIZE(vq)))
+			pass = false;
+
+		if (!compare_buffer("initial SSVE FFR",
+				    iov.iov_base + SVE_PT_SVE_FFR_OFFSET(vq),
+				    ffr_in, SVE_PT_SVE_PREG_SIZE(vq)))
+			pass = false;
+	} else {
+		fpsimd = iov.iov_base + SVE_PT_FPSIMD_OFFSET;
+		if (!compare_buffer("initial V via SSVE",
+				    &fpsimd->vregs[0], v_in, sizeof(v_in)))
+			pass = false;
+	}
+
+out:
+	free(iov.iov_base);
+	return pass;
+}
+
+static bool check_ptrace_values_za(pid_t child, struct test_config *config)
+{
+	struct user_za_header *za;
+	struct iovec iov;
+	int ret, vq;
+	bool pass = true;
+
+	if (!sme_supported())
+		return true;
+
+	vq = __sve_vq_from_vl(config->sme_vl_in);
+
+	iov.iov_len = ZA_SIG_CONTEXT_SIZE(vq);
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		ksft_print_msg("OOM allocating %lu byte ZA buffer\n",
+			       iov.iov_len);
+		return false;
+	}
+
+	ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_ZA, &iov);
+	if (ret != 0) {
+		ksft_print_msg("Failed to read initial ZA: %s (%d)\n",
+			       strerror(errno), errno);
+		pass = false;
+		goto out;
+	}
+
+	za = iov.iov_base;
+
+	if (za->vl != config->sme_vl_in) {
+		ksft_print_msg("Mismatch in initial SME VL: %d != %d\n",
+			       za->vl, config->sme_vl_in);
+		pass = false;
+	}
+
+	/* If PSTATE.ZA is not set we should just read the header */
+	if (config->svcr_in & SVCR_ZA) {
+		if (za->size != ZA_PT_SIZE(vq)) {
+			ksft_print_msg("Unexpected ZA ptrace read size: %d != %lu\n",
+				       za->size, ZA_PT_SIZE(vq));
+			pass = false;
+		}
+
+		if (!compare_buffer("initial ZA",
+				    iov.iov_base + ZA_PT_ZA_OFFSET,
+				    za_in, ZA_PT_ZA_SIZE(vq)))
+			pass = false;
+	} else {
+		if (za->size != sizeof(*za)) {
+			ksft_print_msg("Unexpected ZA ptrace read size: %d != %lu\n",
+				       za->size, sizeof(*za));
+			pass = false;
+		}
+	}
+
+out:
+	free(iov.iov_base);
+	return pass;
+}
+
+static bool check_ptrace_values_zt(pid_t child, struct test_config *config)
+{
+	uint8_t buf[512];
+	struct iovec iov;
+	int ret;
+
+	if (!sme2_supported())
+		return true;
+
+	iov.iov_base = &buf;
+	iov.iov_len = ZT_SIG_REG_BYTES;
+	ret = ptrace(PTRACE_GETREGSET, child, NT_ARM_ZT, &iov);
+	if (ret != 0) {
+		ksft_print_msg("Failed to read initial ZT: %s (%d)\n",
+			       strerror(errno), errno);
+		return false;
+	}
+
+	return compare_buffer("initial ZT", buf, zt_in, ZT_SIG_REG_BYTES);
+}
+
+
+static bool check_ptrace_values(pid_t child, struct test_config *config)
+{
+	bool pass = true;
+	struct user_fpsimd_state fpsimd;
+	struct iovec iov;
+	int ret;
+
+	iov.iov_base = &fpsimd;
+	iov.iov_len = sizeof(fpsimd);
+	ret = ptrace(PTRACE_GETREGSET, child, NT_PRFPREG, &iov);
+	if (ret == 0) {
+		if (!compare_buffer("initial V", &fpsimd.vregs, v_in,
+				    sizeof(v_in))) {
+			pass = false;
+		}
+	} else {
+		ksft_print_msg("Failed to read initial V: %s (%d)\n",
+			       strerror(errno), errno);
+		pass = false;
+	}
+
+	if (!check_ptrace_values_sve(child, config))
+		pass = false;
+
+	if (!check_ptrace_values_ssve(child, config))
+		pass = false;
+
+	if (!check_ptrace_values_za(child, config))
+		pass = false;
+
+	if (!check_ptrace_values_zt(child, config))
+		pass = false;
+
+	return pass;
+}
+
+static bool run_parent(pid_t child, struct test_definition *test,
+		       struct test_config *config)
+{
+	int wait_status, ret;
+	pid_t pid;
+	bool pass;
+
+	/* Initial attach */
+	while (1) {
+		pid = waitpid(child, &wait_status, 0);
+		if (pid < 0) {
+			if (errno == EINTR)
+				continue;
+			ksft_exit_fail_msg("waitpid() failed: %s (%d)\n",
+					   strerror(errno), errno);
+		}
+
+		if (pid == child)
+			break;
+	}
+
+	if (WIFEXITED(wait_status)) {
+		ksft_print_msg("Child exited loading values with status %d\n",
+			       WEXITSTATUS(wait_status));
+		pass = false;
+		goto out;
+	}
+
+	if (WIFSIGNALED(wait_status)) {
+		ksft_print_msg("Child died from signal %d loading values\n",
+			       WTERMSIG(wait_status));
+		pass = false;
+		goto out;
+	}
+
+	/* Read initial values via ptrace */
+	pass = check_ptrace_values(child, config);
+
+	/* Do whatever writes we want to do */
+	if (test->modify_values)
+		test->modify_values(child, config);
+
+	if (!continue_breakpoint(child, PTRACE_CONT))
+		goto cleanup;
+
+	while (1) {
+		pid = waitpid(child, &wait_status, 0);
+		if (pid < 0) {
+			if (errno == EINTR)
+				continue;
+			ksft_exit_fail_msg("waitpid() failed: %s (%d)\n",
+					   strerror(errno), errno);
+		}
+
+		if (pid == child)
+			break;
+	}
+
+	if (WIFEXITED(wait_status)) {
+		ksft_print_msg("Child exited saving values with status %d\n",
+			       WEXITSTATUS(wait_status));
+		pass = false;
+		goto out;
+	}
+
+	if (WIFSIGNALED(wait_status)) {
+		ksft_print_msg("Child died from signal %d saving values\n",
+			       WTERMSIG(wait_status));
+		pass = false;
+		goto out;
+	}
+
+	/* See what happened as a result */
+	read_child_regs(child);
+
+	if (!continue_breakpoint(child, PTRACE_DETACH))
+		goto cleanup;
+
+	/* The child should exit cleanly */
+	got_alarm = false;
+	alarm(1);
+	while (1) {
+		if (got_alarm) {
+			ksft_print_msg("Wait for child timed out\n");
+			goto cleanup;
+		}
+
+		pid = waitpid(child, &wait_status, 0);
+		if (pid < 0) {
+			if (errno == EINTR)
+				continue;
+			ksft_exit_fail_msg("waitpid() failed: %s (%d)\n",
+					   strerror(errno), errno);
+		}
+
+		if (pid == child)
+			break;
+	}
+	alarm(0);
+
+	if (got_alarm) {
+		ksft_print_msg("Timed out waiting for child\n");
+		pass = false;
+		goto cleanup;
+	}
+
+	if (pid == child && WIFSIGNALED(wait_status)) {
+		ksft_print_msg("Child died from signal %d cleaning up\n",
+			       WTERMSIG(wait_status));
+		pass = false;
+		goto out;
+	}
+
+	if (pid == child && WIFEXITED(wait_status)) {
+		if (WEXITSTATUS(wait_status) != 0) {
+			ksft_print_msg("Child exited with error %d\n",
+				       WEXITSTATUS(wait_status));
+			pass = false;
+		}
+	} else {
+		ksft_print_msg("Child did not exit cleanly\n");
+		pass = false;
+		goto cleanup;
+	}
+
+	goto out;
+
+cleanup:
+	ret = kill(child, SIGKILL);
+	if (ret != 0) {
+		ksft_print_msg("kill() failed: %s (%d)\n",
+			       strerror(errno), errno);
+		return false;
+	}
+
+	while (1) {
+		pid = waitpid(child, &wait_status, 0);
+		if (pid < 0) {
+			if (errno == EINTR)
+				continue;
+			ksft_exit_fail_msg("waitpid() failed: %s (%d)\n",
+					   strerror(errno), errno);
+		}
+
+		if (pid == child)
+			break;
+	}
+
+out:
+	return pass;
+}
+
+static void fill_random(void *buf, size_t size)
+{
+	int i;
+	uint32_t *lbuf = buf;
+
+	/* random() returns a 32 bit number regardless of the size of long */
+	for (i = 0; i < size / sizeof(uint32_t); i++)
+		lbuf[i] = random();
+}
+
+static void fill_random_ffr(void *buf, size_t vq)
+{
+	uint8_t *lbuf = buf;
+	int bits, i;
+
+	/*
+	 * Only values with a continuous set of 0..n bits set are
+	 * valid for FFR, set all bits then clear a random number of
+	 * high bits.
+	 */
+	memset(buf, 0, __SVE_FFR_SIZE(vq));
+
+	bits = random() % (__SVE_FFR_SIZE(vq) * 8);
+	for (i = 0; i < bits / 8; i++)
+		lbuf[i] = 0xff;
+	if (bits / 8 != __SVE_FFR_SIZE(vq))
+		lbuf[i] = (1 << (bits % 8)) - 1;
+}
+
+static void fpsimd_to_sve(__uint128_t *v, char *z, int vl)
+{
+	int vq = __sve_vq_from_vl(vl);
+	int i;
+	__uint128_t *p;
+
+	if (!vl)
+		return;
+
+	for (i = 0; i < __SVE_NUM_ZREGS; i++) {
+		p = (__uint128_t *)&z[__SVE_ZREG_OFFSET(vq, i)];
+		*p = arm64_cpu_to_le128(v[i]);
+	}
+}
+
+static void set_initial_values(struct test_config *config)
+{
+	int vq = __sve_vq_from_vl(vl_in(config));
+	int sme_vq = __sve_vq_from_vl(config->sme_vl_in);
+
+	svcr_in = config->svcr_in;
+	svcr_expected = config->svcr_expected;
+	svcr_out = 0;
+
+	fill_random(&v_in, sizeof(v_in));
+	memcpy(v_expected, v_in, sizeof(v_in));
+	memset(v_out, 0, sizeof(v_out));
+
+	/* Changes will be handled in the test case */
+	if (sve_supported() || (config->svcr_in & SVCR_SM)) {
+		/* The low 128 bits of Z are shared with the V registers */
+		fill_random(&z_in, __SVE_ZREGS_SIZE(vq));
+		fpsimd_to_sve(v_in, z_in, vl_in(config));
+		memcpy(z_expected, z_in, __SVE_ZREGS_SIZE(vq));
+		memset(z_out, 0, sizeof(z_out));
+
+		fill_random(&p_in, __SVE_PREGS_SIZE(vq));
+		memcpy(p_expected, p_in, __SVE_PREGS_SIZE(vq));
+		memset(p_out, 0, sizeof(p_out));
+
+		if ((config->svcr_in & SVCR_SM) && !fa64_supported())
+			memset(ffr_in, 0, __SVE_PREG_SIZE(vq));
+		else
+			fill_random_ffr(&ffr_in, vq);
+		memcpy(ffr_expected, ffr_in, __SVE_PREG_SIZE(vq));
+		memset(ffr_out, 0, __SVE_PREG_SIZE(vq));
+	}
+
+	if (config->svcr_in & SVCR_ZA)
+		fill_random(za_in, ZA_SIG_REGS_SIZE(sme_vq));
+	else
+		memset(za_in, 0, ZA_SIG_REGS_SIZE(sme_vq));
+	if (config->svcr_expected & SVCR_ZA)
+		memcpy(za_expected, za_in, ZA_SIG_REGS_SIZE(sme_vq));
+	else
+		memset(za_expected, 0, ZA_SIG_REGS_SIZE(sme_vq));
+	if (sme_supported())
+		memset(za_out, 0, sizeof(za_out));
+
+	if (sme2_supported()) {
+		if (config->svcr_in & SVCR_ZA)
+			fill_random(zt_in, ZT_SIG_REG_BYTES);
+		else
+			memset(zt_in, 0, ZT_SIG_REG_BYTES);
+		if (config->svcr_expected & SVCR_ZA)
+			memcpy(zt_expected, zt_in, ZT_SIG_REG_BYTES);
+		else
+			memset(zt_expected, 0, ZT_SIG_REG_BYTES);
+		memset(zt_out, 0, sizeof(zt_out));
+	}
+}
+
+static bool check_memory_values(struct test_config *config)
+{
+	bool pass = true;
+	int vq, sme_vq;
+
+	if (!compare_buffer("saved V", v_out, v_expected, sizeof(v_out)))
+		pass = false;
+
+	vq = __sve_vq_from_vl(vl_expected(config));
+	sme_vq = __sve_vq_from_vl(config->sme_vl_expected);
+
+	if (svcr_out != svcr_expected) {
+		ksft_print_msg("Mismatch in saved SVCR %lx != %lx\n",
+			       svcr_out, svcr_expected);
+		pass = false;
+	}
+
+	if (sve_vl_out != config->sve_vl_expected) {
+		ksft_print_msg("Mismatch in SVE VL: %ld != %d\n",
+			       sve_vl_out, config->sve_vl_expected);
+		pass = false;
+	}
+
+	if (sme_vl_out != config->sme_vl_expected) {
+		ksft_print_msg("Mismatch in SME VL: %ld != %d\n",
+			       sme_vl_out, config->sme_vl_expected);
+		pass = false;
+	}
+
+	if (!compare_buffer("saved Z", z_out, z_expected,
+			    __SVE_ZREGS_SIZE(vq)))
+		pass = false;
+
+	if (!compare_buffer("saved P", p_out, p_expected,
+			    __SVE_PREGS_SIZE(vq)))
+		pass = false;
+
+	if (!compare_buffer("saved FFR", ffr_out, ffr_expected,
+			    __SVE_PREG_SIZE(vq)))
+		pass = false;
+
+	if (!compare_buffer("saved ZA", za_out, za_expected,
+			    ZA_PT_ZA_SIZE(sme_vq)))
+		pass = false;
+
+	if (!compare_buffer("saved ZT", zt_out, zt_expected, ZT_SIG_REG_BYTES))
+		pass = false;
+
+	return pass;
+}
+
+static bool sve_sme_same(struct test_config *config)
+{
+	if (config->sve_vl_in != config->sve_vl_expected)
+		return false;
+
+	if (config->sme_vl_in != config->sme_vl_expected)
+		return false;
+
+	if (config->svcr_in != config->svcr_expected)
+		return false;
+
+	return true;
+}
+
+static bool sve_write_supported(struct test_config *config)
+{
+	if (!sve_supported() && !sme_supported())
+		return false;
+
+	if ((config->svcr_in & SVCR_ZA) != (config->svcr_expected & SVCR_ZA))
+		return false;
+
+	if (config->svcr_expected & SVCR_SM) {
+		if (config->sve_vl_in != config->sve_vl_expected) {
+			return false;
+		}
+
+		/* Changing the SME VL disables ZA */
+		if ((config->svcr_expected & SVCR_ZA) &&
+		    (config->sme_vl_in != config->sme_vl_expected)) {
+			return false;
+		}
+	} else {
+		if (config->sme_vl_in != config->sme_vl_expected) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+static void fpsimd_write_expected(struct test_config *config)
+{
+	int vl;
+
+	fill_random(&v_expected, sizeof(v_expected));
+
+	/* The SVE registers are flushed by a FPSIMD write */
+	vl = vl_expected(config);
+
+	memset(z_expected, 0, __SVE_ZREGS_SIZE(__sve_vq_from_vl(vl)));
+	memset(p_expected, 0, __SVE_PREGS_SIZE(__sve_vq_from_vl(vl)));
+	memset(ffr_expected, 0, __SVE_PREG_SIZE(__sve_vq_from_vl(vl)));
+
+	fpsimd_to_sve(v_expected, z_expected, vl);
+}
+
+static void fpsimd_write(pid_t child, struct test_config *test_config)
+{
+	struct user_fpsimd_state fpsimd;
+	struct iovec iov;
+	int ret;
+
+	memset(&fpsimd, 0, sizeof(fpsimd));
+	memcpy(&fpsimd.vregs, v_expected, sizeof(v_expected));
+
+	iov.iov_base = &fpsimd;
+	iov.iov_len = sizeof(fpsimd);
+	ret = ptrace(PTRACE_SETREGSET, child, NT_PRFPREG, &iov);
+	if (ret == -1)
+		ksft_print_msg("FPSIMD set failed: (%s) %d\n",
+			       strerror(errno), errno);
+}
+
+static void sve_write_expected(struct test_config *config)
+{
+	int vl = vl_expected(config);
+	int sme_vq = __sve_vq_from_vl(config->sme_vl_expected);
+
+	fill_random(z_expected, __SVE_ZREGS_SIZE(__sve_vq_from_vl(vl)));
+	fill_random(p_expected, __SVE_PREGS_SIZE(__sve_vq_from_vl(vl)));
+
+	if ((svcr_expected & SVCR_SM) && !fa64_supported())
+		memset(ffr_expected, 0, __SVE_PREG_SIZE(sme_vq));
+	else
+		fill_random_ffr(ffr_expected, __sve_vq_from_vl(vl));
+
+	/* Share the low bits of Z with V */
+	fill_random(&v_expected, sizeof(v_expected));
+	fpsimd_to_sve(v_expected, z_expected, vl);
+
+	if (config->sme_vl_in != config->sme_vl_expected) {
+		memset(za_expected, 0, ZA_PT_ZA_SIZE(sme_vq));
+		memset(zt_expected, 0, sizeof(zt_expected));
+	}
+}
+
+static void sve_write(pid_t child, struct test_config *config)
+{
+	struct user_sve_header *sve;
+	struct iovec iov;
+	int ret, vl, vq, regset;
+
+	vl = vl_expected(config);
+	vq = __sve_vq_from_vl(vl);
+
+	iov.iov_len = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE);
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		ksft_print_msg("Failed allocating %lu byte SVE write buffer\n",
+			       iov.iov_len);
+		return;
+	}
+	memset(iov.iov_base, 0, iov.iov_len);
+
+	sve = iov.iov_base;
+	sve->size = iov.iov_len;
+	sve->flags = SVE_PT_REGS_SVE;
+	sve->vl = vl;
+
+	memcpy(iov.iov_base + SVE_PT_SVE_ZREG_OFFSET(vq, 0),
+	       z_expected, SVE_PT_SVE_ZREGS_SIZE(vq));
+	memcpy(iov.iov_base + SVE_PT_SVE_PREG_OFFSET(vq, 0),
+	       p_expected, SVE_PT_SVE_PREGS_SIZE(vq));
+	memcpy(iov.iov_base + SVE_PT_SVE_FFR_OFFSET(vq),
+	       ffr_expected, SVE_PT_SVE_PREG_SIZE(vq));
+
+	if (svcr_expected & SVCR_SM)
+		regset = NT_ARM_SSVE;
+	else
+		regset = NT_ARM_SVE;
+
+	ret = ptrace(PTRACE_SETREGSET, child, regset, &iov);
+	if (ret != 0)
+		ksft_print_msg("Failed to write SVE: %s (%d)\n",
+			       strerror(errno), errno);
+
+	free(iov.iov_base);
+}
+
+static bool za_write_supported(struct test_config *config)
+{
+	if (config->svcr_expected & SVCR_SM) {
+		if (!(config->svcr_in & SVCR_SM))
+			return false;
+
+		/* Changing the SME VL exits streaming mode */
+		if (config->sme_vl_in != config->sme_vl_expected) {
+			return false;
+		}
+	}
+
+	/* Can't disable SM outside a VL change */
+	if ((config->svcr_in & SVCR_SM) &&
+	    !(config->svcr_expected & SVCR_SM))
+		return false;
+
+	return true;
+}
+
+static void za_write_expected(struct test_config *config)
+{
+	int sme_vq, sve_vq;
+
+	sme_vq = __sve_vq_from_vl(config->sme_vl_expected);
+
+	if (config->svcr_expected & SVCR_ZA) {
+		fill_random(za_expected, ZA_PT_ZA_SIZE(sme_vq));
+	} else {
+		memset(za_expected, 0, ZA_PT_ZA_SIZE(sme_vq));
+		memset(zt_expected, 0, sizeof(zt_expected));
+	}
+
+	/* Changing the SME VL flushes ZT, SVE state and exits SM */
+	if (config->sme_vl_in != config->sme_vl_expected) {
+		svcr_expected &= ~SVCR_SM;
+
+		sve_vq = __sve_vq_from_vl(vl_expected(config));
+		memset(z_expected, 0, __SVE_ZREGS_SIZE(sve_vq));
+		memset(p_expected, 0, __SVE_PREGS_SIZE(sve_vq));
+		memset(ffr_expected, 0, __SVE_PREG_SIZE(sve_vq));
+		memset(zt_expected, 0, sizeof(zt_expected));
+
+		fpsimd_to_sve(v_expected, z_expected, vl_expected(config));
+	}
+}
+
+static void za_write(pid_t child, struct test_config *config)
+{
+	struct user_za_header *za;
+	struct iovec iov;
+	int ret, vq;
+
+	vq = __sve_vq_from_vl(config->sme_vl_expected);
+
+	if (config->svcr_expected & SVCR_ZA)
+		iov.iov_len = ZA_PT_SIZE(vq);
+	else
+		iov.iov_len = sizeof(*za);
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		ksft_print_msg("Failed allocating %lu byte ZA write buffer\n",
+			       iov.iov_len);
+		return;
+	}
+	memset(iov.iov_base, 0, iov.iov_len);
+
+	za = iov.iov_base;
+	za->size = iov.iov_len;
+	za->vl = config->sme_vl_expected;
+	if (config->svcr_expected & SVCR_ZA)
+		memcpy(iov.iov_base + ZA_PT_ZA_OFFSET, za_expected,
+		       ZA_PT_ZA_SIZE(vq));
+
+	ret = ptrace(PTRACE_SETREGSET, child, NT_ARM_ZA, &iov);
+	if (ret != 0)
+		ksft_print_msg("Failed to write ZA: %s (%d)\n",
+			       strerror(errno), errno);
+
+	free(iov.iov_base);
+}
+
+static bool zt_write_supported(struct test_config *config)
+{
+	if (!sme2_supported())
+		return false;
+	if (config->sme_vl_in != config->sme_vl_expected)
+		return false;
+	if (!(config->svcr_expected & SVCR_ZA))
+		return false;
+	if ((config->svcr_in & SVCR_SM) != (config->svcr_expected & SVCR_SM))
+		return false;
+
+	return true;
+}
+
+static void zt_write_expected(struct test_config *config)
+{
+	int sme_vq;
+
+	sme_vq = __sve_vq_from_vl(config->sme_vl_expected);
+
+	if (config->svcr_expected & SVCR_ZA) {
+		fill_random(zt_expected, sizeof(zt_expected));
+	} else {
+		memset(za_expected, 0, ZA_PT_ZA_SIZE(sme_vq));
+		memset(zt_expected, 0, sizeof(zt_expected));
+	}
+}
+
+static void zt_write(pid_t child, struct test_config *config)
+{
+	struct iovec iov;
+	int ret;
+
+	iov.iov_len = ZT_SIG_REG_BYTES;
+	iov.iov_base = zt_expected;
+	ret = ptrace(PTRACE_SETREGSET, child, NT_ARM_ZT, &iov);
+	if (ret != 0)
+		ksft_print_msg("Failed to write ZT: %s (%d)\n",
+			       strerror(errno), errno);
+}
+
+/* Actually run a test */
+static void run_test(struct test_definition *test, struct test_config *config)
+{
+	pid_t child;
+	char name[1024];
+	bool pass;
+
+	if (sve_supported() && sme_supported())
+		snprintf(name, sizeof(name), "%s, SVE %d->%d, SME %d/%x->%d/%x",
+			 test->name,
+			 config->sve_vl_in, config->sve_vl_expected,
+			 config->sme_vl_in, config->svcr_in,
+			 config->sme_vl_expected, config->svcr_expected);
+	else if (sve_supported())
+		snprintf(name, sizeof(name), "%s, SVE %d->%d", test->name,
+			 config->sve_vl_in, config->sve_vl_expected);
+	else if (sme_supported())
+		snprintf(name, sizeof(name), "%s, SME %d/%x->%d/%x",
+			 test->name,
+			 config->sme_vl_in, config->svcr_in,
+			 config->sme_vl_expected, config->svcr_expected);
+	else
+		snprintf(name, sizeof(name), "%s", test->name);
+
+	if (test->supported && !test->supported(config)) {
+		ksft_test_result_skip("%s\n", name);
+		return;
+	}
+
+	set_initial_values(config);
+
+	if (test->set_expected_values)
+		test->set_expected_values(config);
+
+	child = fork();
+	if (child < 0)
+		ksft_exit_fail_msg("fork() failed: %s (%d)\n",
+				   strerror(errno), errno);
+	/* run_child() never returns */
+	if (child == 0)
+		run_child(config);
+
+	pass = run_parent(child, test, config);
+	if (!check_memory_values(config))
+		pass = false;
+
+	ksft_test_result(pass, "%s\n", name);
+}
+
+static void run_tests(struct test_definition defs[], int count,
+		      struct test_config *config)
+{
+	int i;
+
+	for (i = 0; i < count; i++)
+		run_test(&defs[i], config);
+}
+
+static struct test_definition base_test_defs[] = {
+	{
+		.name = "No writes",
+		.supported = sve_sme_same,
+	},
+	{
+		.name = "FPSIMD write",
+		.supported = sve_sme_same,
+		.set_expected_values = fpsimd_write_expected,
+		.modify_values = fpsimd_write,
+	},
+};
+
+static struct test_definition sve_test_defs[] = {
+	{
+		.name = "SVE write",
+		.supported = sve_write_supported,
+		.set_expected_values = sve_write_expected,
+		.modify_values = sve_write,
+	},
+};
+
+static struct test_definition za_test_defs[] = {
+	{
+		.name = "ZA write",
+		.supported = za_write_supported,
+		.set_expected_values = za_write_expected,
+		.modify_values = za_write,
+	},
+};
+
+static struct test_definition zt_test_defs[] = {
+	{
+		.name = "ZT write",
+		.supported = zt_write_supported,
+		.set_expected_values = zt_write_expected,
+		.modify_values = zt_write,
+	},
+};
+
+static int sve_vls[MAX_NUM_VLS], sme_vls[MAX_NUM_VLS];
+static int sve_vl_count, sme_vl_count;
+
+static void probe_vls(const char *name, int vls[], int *vl_count, int set_vl)
+{
+	unsigned int vq;
+	int vl;
+
+	*vl_count = 0;
+
+	for (vq = ARCH_VQ_MAX; vq > 0; vq /= 2) {
+		vl = prctl(set_vl, vq * 16);
+		if (vl == -1)
+			ksft_exit_fail_msg("SET_VL failed: %s (%d)\n",
+					   strerror(errno), errno);
+
+		vl &= PR_SVE_VL_LEN_MASK;
+
+		if (*vl_count && (vl == vls[*vl_count - 1]))
+			break;
+
+		vq = sve_vq_from_vl(vl);
+
+		vls[*vl_count] = vl;
+		*vl_count += 1;
+	}
+
+	if (*vl_count > 2) {
+		/* Just use the minimum and maximum */
+		vls[1] = vls[*vl_count - 1];
+		ksft_print_msg("%d %s VLs, using %d and %d\n",
+			       *vl_count, name, vls[0], vls[1]);
+		*vl_count = 2;
+	} else {
+		ksft_print_msg("%d %s VLs\n", *vl_count, name);
+	}
+}
+
+static struct {
+	int svcr_in, svcr_expected;
+} svcr_combinations[] = {
+	{ .svcr_in = 0, .svcr_expected = 0, },
+	{ .svcr_in = 0, .svcr_expected = SVCR_SM, },
+	{ .svcr_in = 0, .svcr_expected = SVCR_ZA, },
+	/* Can't enable both SM and ZA with a single ptrace write */
+
+	{ .svcr_in = SVCR_SM, .svcr_expected = 0, },
+	{ .svcr_in = SVCR_SM, .svcr_expected = SVCR_SM, },
+	{ .svcr_in = SVCR_SM, .svcr_expected = SVCR_ZA, },
+	{ .svcr_in = SVCR_SM, .svcr_expected = SVCR_SM | SVCR_ZA, },
+
+	{ .svcr_in = SVCR_ZA, .svcr_expected = 0, },
+	{ .svcr_in = SVCR_ZA, .svcr_expected = SVCR_SM, },
+	{ .svcr_in = SVCR_ZA, .svcr_expected = SVCR_ZA, },
+	{ .svcr_in = SVCR_ZA, .svcr_expected = SVCR_SM | SVCR_ZA, },
+
+	{ .svcr_in = SVCR_SM | SVCR_ZA, .svcr_expected = 0, },
+	{ .svcr_in = SVCR_SM | SVCR_ZA, .svcr_expected = SVCR_SM, },
+	{ .svcr_in = SVCR_SM | SVCR_ZA, .svcr_expected = SVCR_ZA, },
+	{ .svcr_in = SVCR_SM | SVCR_ZA, .svcr_expected = SVCR_SM | SVCR_ZA, },
+};
+
+static void run_sve_tests(void)
+{
+	struct test_config test_config;
+	int i, j;
+
+	if (!sve_supported())
+		return;
+
+	test_config.sme_vl_in = sme_vls[0];
+	test_config.sme_vl_expected = sme_vls[0];
+	test_config.svcr_in = 0;
+	test_config.svcr_expected = 0;
+
+	for (i = 0; i < sve_vl_count; i++) {
+		test_config.sve_vl_in = sve_vls[i];
+
+		for (j = 0; j < sve_vl_count; j++) {
+			test_config.sve_vl_expected = sve_vls[j];
+
+			run_tests(base_test_defs,
+				  ARRAY_SIZE(base_test_defs),
+				  &test_config);
+			if (sve_supported())
+				run_tests(sve_test_defs,
+					  ARRAY_SIZE(sve_test_defs),
+					  &test_config);
+		}
+	}
+
+}
+
+static void run_sme_tests(void)
+{
+	struct test_config test_config;
+	int i, j, k;
+
+	if (!sme_supported())
+		return;
+
+	test_config.sve_vl_in = sve_vls[0];
+	test_config.sve_vl_expected = sve_vls[0];
+
+	/*
+	 * Every SME VL/SVCR combination
+	 */
+	for (i = 0; i < sme_vl_count; i++) {
+		test_config.sme_vl_in = sme_vls[i];
+
+		for (j = 0; j < sme_vl_count; j++) {
+			test_config.sme_vl_expected = sme_vls[j];
+
+			for (k = 0; k < ARRAY_SIZE(svcr_combinations); k++) {
+				test_config.svcr_in = svcr_combinations[k].svcr_in;
+				test_config.svcr_expected = svcr_combinations[k].svcr_expected;
+
+				run_tests(base_test_defs,
+					  ARRAY_SIZE(base_test_defs),
+					  &test_config);
+				run_tests(sve_test_defs,
+					  ARRAY_SIZE(sve_test_defs),
+					  &test_config);
+				run_tests(za_test_defs,
+					  ARRAY_SIZE(za_test_defs),
+					  &test_config);
+
+				if (sme2_supported())
+					run_tests(zt_test_defs,
+						  ARRAY_SIZE(zt_test_defs),
+						  &test_config);
+			}
+		}
+	}
+}
+
+int main(void)
+{
+	struct test_config test_config;
+	struct sigaction sa;
+	int tests, ret, tmp;
+
+	srandom(getpid());
+
+	ksft_print_header();
+
+	if (sve_supported()) {
+		probe_vls("SVE", sve_vls, &sve_vl_count, PR_SVE_SET_VL);
+
+		tests = ARRAY_SIZE(base_test_defs) +
+			ARRAY_SIZE(sve_test_defs);
+		tests *= sve_vl_count * sve_vl_count;
+	} else {
+		/* Only run the FPSIMD tests */
+		sve_vl_count = 1;
+		tests = ARRAY_SIZE(base_test_defs);
+	}
+
+	if (sme_supported()) {
+		probe_vls("SME", sme_vls, &sme_vl_count, PR_SME_SET_VL);
+
+		tmp = ARRAY_SIZE(base_test_defs) + ARRAY_SIZE(sve_test_defs)
+			+ ARRAY_SIZE(za_test_defs);
+
+		if (sme2_supported())
+			tmp += ARRAY_SIZE(zt_test_defs);
+
+		tmp *= sme_vl_count * sme_vl_count;
+		tmp *= ARRAY_SIZE(svcr_combinations);
+		tests += tmp;
+	} else {
+		sme_vl_count = 1;
+	}
+
+	if (sme2_supported())
+		ksft_print_msg("SME2 supported\n");
+
+	if (fa64_supported())
+		ksft_print_msg("FA64 supported\n");
+
+	ksft_set_plan(tests);
+
+	/* Get signal handers ready before we start any children */
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_sigaction = handle_alarm;
+	sa.sa_flags = SA_RESTART | SA_SIGINFO;
+	sigemptyset(&sa.sa_mask);
+	ret = sigaction(SIGALRM, &sa, NULL);
+	if (ret < 0)
+		ksft_print_msg("Failed to install SIGALRM handler: %s (%d)\n",
+			       strerror(errno), errno);
+
+	/*
+	 * Run the test set if there is no SVE or SME, with those we
+	 * have to pick a VL for each run.
+	 */
+	if (!sve_supported()) {
+		test_config.sve_vl_in = 0;
+		test_config.sve_vl_expected = 0;
+		test_config.sme_vl_in = 0;
+		test_config.sme_vl_expected = 0;
+		test_config.svcr_in = 0;
+		test_config.svcr_expected = 0;
+
+		run_tests(base_test_defs, ARRAY_SIZE(base_test_defs),
+			  &test_config);
+	}
+
+	run_sve_tests();
+	run_sme_tests();
+
+	ksft_finished();
+}
diff --git a/tools/testing/selftests/arm64/fp/fp-ptrace.h b/tools/testing/selftests/arm64/fp/fp-ptrace.h
new file mode 100644
index 0000000000..db4f2c4d75
--- /dev/null
+++ b/tools/testing/selftests/arm64/fp/fp-ptrace.h
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2021-3 ARM Limited.
+
+#ifndef FP_PTRACE_H
+#define FP_PTRACE_H
+
+#define SVCR_SM_SHIFT 0
+#define SVCR_ZA_SHIFT 1
+
+#define SVCR_SM (1 << SVCR_SM_SHIFT)
+#define SVCR_ZA (1 << SVCR_ZA_SHIFT)
+
+#endif