Merge branch 'for-next/late-arrivals' into for-next/core

Late patches for 5.10: MTE selftests, minor KCSAN preparation and removal
of some unused prototypes.

(Amit Daniel Kachhap and others)
* for-next/late-arrivals:
  arm64: random: Remove no longer needed prototypes
  arm64: initialize per-cpu offsets earlier
  kselftest/arm64: Check mte tagged user address in kernel
  kselftest/arm64: Verify KSM page merge for MTE pages
  kselftest/arm64: Verify all different mmap MTE options
  kselftest/arm64: Check forked child mte memory accessibility
  kselftest/arm64: Verify mte tag inclusion via prctl
  kselftest/arm64: Add utilities and a test to validate mte memory

13 files changed, 2070 insertions, 1 deletions

diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile
index 463d56278f8f..2c9d012797a7 100644
--- a/tools/testing/selftests/arm64/Makefile
+++ b/tools/testing/selftests/arm64/Makefile
@@ -4,7 +4,7 @@
 ARCH ?= $(shell uname -m 2>/dev/null || echo not)
 
 ifneq (,$(filter $(ARCH),aarch64 arm64))
-ARM64_SUBTARGETS ?= tags signal pauth fp
+ARM64_SUBTARGETS ?= tags signal pauth fp mte
 else
 ARM64_SUBTARGETS :=
 endif
diff --git a/tools/testing/selftests/arm64/mte/.gitignore b/tools/testing/selftests/arm64/mte/.gitignore
new file mode 100644
index 000000000000..bc3ac63f3314
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/.gitignore
@@ -0,0 +1,6 @@
+check_buffer_fill
+check_tags_inclusion
+check_child_memory
+check_mmap_options
+check_ksm_options
+check_user_mem
diff --git a/tools/testing/selftests/arm64/mte/Makefile b/tools/testing/selftests/arm64/mte/Makefile
new file mode 100644
index 000000000000..2480226dfe57
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/Makefile
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020 ARM Limited
+
+CFLAGS += -std=gnu99 -I.
+SRCS := $(filter-out mte_common_util.c,$(wildcard *.c))
+PROGS := $(patsubst %.c,%,$(SRCS))
+
+#Add mte compiler option
+ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep gcc),)
+CFLAGS += -march=armv8.5-a+memtag
+endif
+
+#check if the compiler works well
+mte_cc_support := $(shell if ($(CC) $(CFLAGS) -E -x c /dev/null -o /dev/null 2>&1) then echo "1"; fi)
+
+ifeq ($(mte_cc_support),1)
+# Generated binaries to be installed by top KSFT script
+TEST_GEN_PROGS := $(PROGS)
+
+# Get Kernel headers installed and use them.
+KSFT_KHDR_INSTALL := 1
+endif
+
+# Include KSFT lib.mk.
+include ../../lib.mk
+
+ifeq ($(mte_cc_support),1)
+$(TEST_GEN_PROGS): mte_common_util.c mte_common_util.h mte_helper.S
+endif
diff --git a/tools/testing/selftests/arm64/mte/check_buffer_fill.c b/tools/testing/selftests/arm64/mte/check_buffer_fill.c
new file mode 100644
index 000000000000..242635d79035
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/check_buffer_fill.c
@@ -0,0 +1,475 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 ARM Limited
+
+#define _GNU_SOURCE
+
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "kselftest.h"
+#include "mte_common_util.h"
+#include "mte_def.h"
+
+#define OVERFLOW_RANGE MT_GRANULE_SIZE
+
+static int sizes[] = {
+	1, 555, 1033, MT_GRANULE_SIZE - 1, MT_GRANULE_SIZE,
+	/* page size - 1*/ 0, /* page_size */ 0, /* page size + 1 */ 0
+};
+
+enum mte_block_test_alloc {
+	UNTAGGED_TAGGED,
+	TAGGED_UNTAGGED,
+	TAGGED_TAGGED,
+	BLOCK_ALLOC_MAX,
+};
+
+static int check_buffer_by_byte(int mem_type, int mode)
+{
+	char *ptr;
+	int i, j, item;
+	bool err;
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	item = sizeof(sizes)/sizeof(int);
+
+	for (i = 0; i < item; i++) {
+		ptr = (char *)mte_allocate_memory(sizes[i], mem_type, 0, true);
+		if (check_allocated_memory(ptr, sizes[i], mem_type, true) != KSFT_PASS)
+			return KSFT_FAIL;
+		mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[i]);
+		/* Set some value in tagged memory */
+		for (j = 0; j < sizes[i]; j++)
+			ptr[j] = '1';
+		mte_wait_after_trig();
+		err = cur_mte_cxt.fault_valid;
+		/* Check the buffer whether it is filled. */
+		for (j = 0; j < sizes[i] && !err; j++) {
+			if (ptr[j] != '1')
+				err = true;
+		}
+		mte_free_memory((void *)ptr, sizes[i], mem_type, true);
+
+		if (err)
+			break;
+	}
+	if (!err)
+		return KSFT_PASS;
+	else
+		return KSFT_FAIL;
+}
+
+static int check_buffer_underflow_by_byte(int mem_type, int mode,
+					  int underflow_range)
+{
+	char *ptr;
+	int i, j, item, last_index;
+	bool err;
+	char *und_ptr = NULL;
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	item = sizeof(sizes)/sizeof(int);
+	for (i = 0; i < item; i++) {
+		ptr = (char *)mte_allocate_memory_tag_range(sizes[i], mem_type, 0,
+							    underflow_range, 0);
+		if (check_allocated_memory_range(ptr, sizes[i], mem_type,
+					       underflow_range, 0) != KSFT_PASS)
+			return KSFT_FAIL;
+
+		mte_initialize_current_context(mode, (uintptr_t)ptr, -underflow_range);
+		last_index = 0;
+		/* Set some value in tagged memory and make the buffer underflow */
+		for (j = sizes[i] - 1; (j >= -underflow_range) &&
+				       (cur_mte_cxt.fault_valid == false); j--) {
+			ptr[j] = '1';
+			last_index = j;
+		}
+		mte_wait_after_trig();
+		err = false;
+		/* Check whether the buffer is filled */
+		for (j = 0; j < sizes[i]; j++) {
+			if (ptr[j] != '1') {
+				err = true;
+				ksft_print_msg("Buffer is not filled at index:%d of ptr:0x%lx\n",
+						j, ptr);
+				break;
+			}
+		}
+		if (err)
+			goto check_buffer_underflow_by_byte_err;
+
+		switch (mode) {
+		case MTE_NONE_ERR:
+			if (cur_mte_cxt.fault_valid == true || last_index != -underflow_range) {
+				err = true;
+				break;
+			}
+			/* There were no fault so the underflow area should be filled */
+			und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr - underflow_range);
+			for (j = 0 ; j < underflow_range; j++) {
+				if (und_ptr[j] != '1') {
+					err = true;
+					break;
+				}
+			}
+			break;
+		case MTE_ASYNC_ERR:
+			/* Imprecise fault should occur otherwise return error */
+			if (cur_mte_cxt.fault_valid == false) {
+				err = true;
+				break;
+			}
+			/*
+			 * The imprecise fault is checked after the write to the buffer,
+			 * so the underflow area before the fault should be filled.
+			 */
+			und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr);
+			for (j = last_index ; j < 0 ; j++) {
+				if (und_ptr[j] != '1') {
+					err = true;
+					break;
+				}
+			}
+			break;
+		case MTE_SYNC_ERR:
+			/* Precise fault should occur otherwise return error */
+			if (!cur_mte_cxt.fault_valid || (last_index != (-1))) {
+				err = true;
+				break;
+			}
+			/* Underflow area should not be filled */
+			und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr);
+			if (und_ptr[-1] == '1')
+				err = true;
+			break;
+		default:
+			err = true;
+		break;
+		}
+check_buffer_underflow_by_byte_err:
+		mte_free_memory_tag_range((void *)ptr, sizes[i], mem_type, underflow_range, 0);
+		if (err)
+			break;
+	}
+	return (err ? KSFT_FAIL : KSFT_PASS);
+}
+
+static int check_buffer_overflow_by_byte(int mem_type, int mode,
+					  int overflow_range)
+{
+	char *ptr;
+	int i, j, item, last_index;
+	bool err;
+	size_t tagged_size, overflow_size;
+	char *over_ptr = NULL;
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	item = sizeof(sizes)/sizeof(int);
+	for (i = 0; i < item; i++) {
+		ptr = (char *)mte_allocate_memory_tag_range(sizes[i], mem_type, 0,
+							    0, overflow_range);
+		if (check_allocated_memory_range(ptr, sizes[i], mem_type,
+						 0, overflow_range) != KSFT_PASS)
+			return KSFT_FAIL;
+
+		tagged_size = MT_ALIGN_UP(sizes[i]);
+
+		mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[i] + overflow_range);
+
+		/* Set some value in tagged memory and make the buffer underflow */
+		for (j = 0, last_index = 0 ; (j < (sizes[i] + overflow_range)) &&
+					     (cur_mte_cxt.fault_valid == false); j++) {
+			ptr[j] = '1';
+			last_index = j;
+		}
+		mte_wait_after_trig();
+		err = false;
+		/* Check whether the buffer is filled */
+		for (j = 0; j < sizes[i]; j++) {
+			if (ptr[j] != '1') {
+				err = true;
+				ksft_print_msg("Buffer is not filled at index:%d of ptr:0x%lx\n",
+						j, ptr);
+				break;
+			}
+		}
+		if (err)
+			goto check_buffer_overflow_by_byte_err;
+
+		overflow_size = overflow_range - (tagged_size - sizes[i]);
+
+		switch (mode) {
+		case MTE_NONE_ERR:
+			if ((cur_mte_cxt.fault_valid == true) ||
+			    (last_index != (sizes[i] + overflow_range - 1))) {
+				err = true;
+				break;
+			}
+			/* There were no fault so the overflow area should be filled */
+			over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr + tagged_size);
+			for (j = 0 ; j < overflow_size; j++) {
+				if (over_ptr[j] != '1') {
+					err = true;
+					break;
+				}
+			}
+			break;
+		case MTE_ASYNC_ERR:
+			/* Imprecise fault should occur otherwise return error */
+			if (cur_mte_cxt.fault_valid == false) {
+				err = true;
+				break;
+			}
+			/*
+			 * The imprecise fault is checked after the write to the buffer,
+			 * so the overflow area should be filled before the fault.
+			 */
+			over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr);
+			for (j = tagged_size ; j < last_index; j++) {
+				if (over_ptr[j] != '1') {
+					err = true;
+					break;
+				}
+			}
+			break;
+		case MTE_SYNC_ERR:
+			/* Precise fault should occur otherwise return error */
+			if (!cur_mte_cxt.fault_valid || (last_index != tagged_size)) {
+				err = true;
+				break;
+			}
+			/* Underflow area should not be filled */
+			over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr + tagged_size);
+			for (j = 0 ; j < overflow_size; j++) {
+				if (over_ptr[j] == '1')
+					err = true;
+			}
+			break;
+		default:
+			err = true;
+		break;
+		}
+check_buffer_overflow_by_byte_err:
+		mte_free_memory_tag_range((void *)ptr, sizes[i], mem_type, 0, overflow_range);
+		if (err)
+			break;
+	}
+	return (err ? KSFT_FAIL : KSFT_PASS);
+}
+
+static int check_buffer_by_block_iterate(int mem_type, int mode, size_t size)
+{
+	char *src, *dst;
+	int j, result = KSFT_PASS;
+	enum mte_block_test_alloc alloc_type = UNTAGGED_TAGGED;
+
+	for (alloc_type = UNTAGGED_TAGGED; alloc_type < (int) BLOCK_ALLOC_MAX; alloc_type++) {
+		switch (alloc_type) {
+		case UNTAGGED_TAGGED:
+			src = (char *)mte_allocate_memory(size, mem_type, 0, false);
+			if (check_allocated_memory(src, size, mem_type, false) != KSFT_PASS)
+				return KSFT_FAIL;
+
+			dst = (char *)mte_allocate_memory(size, mem_type, 0, true);
+			if (check_allocated_memory(dst, size, mem_type, true) != KSFT_PASS) {
+				mte_free_memory((void *)src, size, mem_type, false);
+				return KSFT_FAIL;
+			}
+
+			break;
+		case TAGGED_UNTAGGED:
+			dst = (char *)mte_allocate_memory(size, mem_type, 0, false);
+			if (check_allocated_memory(dst, size, mem_type, false) != KSFT_PASS)
+				return KSFT_FAIL;
+
+			src = (char *)mte_allocate_memory(size, mem_type, 0, true);
+			if (check_allocated_memory(src, size, mem_type, true) != KSFT_PASS) {
+				mte_free_memory((void *)dst, size, mem_type, false);
+				return KSFT_FAIL;
+			}
+			break;
+		case TAGGED_TAGGED:
+			src = (char *)mte_allocate_memory(size, mem_type, 0, true);
+			if (check_allocated_memory(src, size, mem_type, true) != KSFT_PASS)
+				return KSFT_FAIL;
+
+			dst = (char *)mte_allocate_memory(size, mem_type, 0, true);
+			if (check_allocated_memory(dst, size, mem_type, true) != KSFT_PASS) {
+				mte_free_memory((void *)src, size, mem_type, true);
+				return KSFT_FAIL;
+			}
+			break;
+		default:
+			return KSFT_FAIL;
+		}
+
+		cur_mte_cxt.fault_valid = false;
+		result = KSFT_PASS;
+		mte_initialize_current_context(mode, (uintptr_t)dst, size);
+		/* Set some value in memory and copy*/
+		memset((void *)src, (int)'1', size);
+		memcpy((void *)dst, (void *)src, size);
+		mte_wait_after_trig();
+		if (cur_mte_cxt.fault_valid) {
+			result = KSFT_FAIL;
+			goto check_buffer_by_block_err;
+		}
+		/* Check the buffer whether it is filled. */
+		for (j = 0; j < size; j++) {
+			if (src[j] != dst[j] || src[j] != '1') {
+				result = KSFT_FAIL;
+				break;
+			}
+		}
+check_buffer_by_block_err:
+		mte_free_memory((void *)src, size, mem_type,
+				MT_FETCH_TAG((uintptr_t)src) ? true : false);
+		mte_free_memory((void *)dst, size, mem_type,
+				MT_FETCH_TAG((uintptr_t)dst) ? true : false);
+		if (result != KSFT_PASS)
+			return result;
+	}
+	return result;
+}
+
+static int check_buffer_by_block(int mem_type, int mode)
+{
+	int i, item, result = KSFT_PASS;
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	item = sizeof(sizes)/sizeof(int);
+	cur_mte_cxt.fault_valid = false;
+	for (i = 0; i < item; i++) {
+		result = check_buffer_by_block_iterate(mem_type, mode, sizes[i]);
+		if (result != KSFT_PASS)
+			break;
+	}
+	return result;
+}
+
+static int compare_memory_tags(char *ptr, size_t size, int tag)
+{
+	int i, new_tag;
+
+	for (i = 0 ; i < size ; i += MT_GRANULE_SIZE) {
+		new_tag = MT_FETCH_TAG((uintptr_t)(mte_get_tag_address(ptr + i)));
+		if (tag != new_tag) {
+			ksft_print_msg("FAIL: child mte tag mismatch\n");
+			return KSFT_FAIL;
+		}
+	}
+	return KSFT_PASS;
+}
+
+static int check_memory_initial_tags(int mem_type, int mode, int mapping)
+{
+	char *ptr;
+	int run, fd;
+	int total = sizeof(sizes)/sizeof(int);
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	for (run = 0; run < total; run++) {
+		/* check initial tags for anonymous mmap */
+		ptr = (char *)mte_allocate_memory(sizes[run], mem_type, mapping, false);
+		if (check_allocated_memory(ptr, sizes[run], mem_type, false) != KSFT_PASS)
+			return KSFT_FAIL;
+		if (compare_memory_tags(ptr, sizes[run], 0) != KSFT_PASS) {
+			mte_free_memory((void *)ptr, sizes[run], mem_type, false);
+			return KSFT_FAIL;
+		}
+		mte_free_memory((void *)ptr, sizes[run], mem_type, false);
+
+		/* check initial tags for file mmap */
+		fd = create_temp_file();
+		if (fd == -1)
+			return KSFT_FAIL;
+		ptr = (char *)mte_allocate_file_memory(sizes[run], mem_type, mapping, false, fd);
+		if (check_allocated_memory(ptr, sizes[run], mem_type, false) != KSFT_PASS) {
+			close(fd);
+			return KSFT_FAIL;
+		}
+		if (compare_memory_tags(ptr, sizes[run], 0) != KSFT_PASS) {
+			mte_free_memory((void *)ptr, sizes[run], mem_type, false);
+			close(fd);
+			return KSFT_FAIL;
+		}
+		mte_free_memory((void *)ptr, sizes[run], mem_type, false);
+		close(fd);
+	}
+	return KSFT_PASS;
+}
+
+int main(int argc, char *argv[])
+{
+	int err;
+	size_t page_size = getpagesize();
+	int item = sizeof(sizes)/sizeof(int);
+
+	sizes[item - 3] = page_size - 1;
+	sizes[item - 2] = page_size;
+	sizes[item - 1] = page_size + 1;
+
+	err = mte_default_setup();
+	if (err)
+		return err;
+
+	/* Register SIGSEGV handler */
+	mte_register_signal(SIGSEGV, mte_default_handler);
+
+	/* Buffer by byte tests */
+	evaluate_test(check_buffer_by_byte(USE_MMAP, MTE_SYNC_ERR),
+	"Check buffer correctness by byte with sync err mode and mmap memory\n");
+	evaluate_test(check_buffer_by_byte(USE_MMAP, MTE_ASYNC_ERR),
+	"Check buffer correctness by byte with async err mode and mmap memory\n");
+	evaluate_test(check_buffer_by_byte(USE_MPROTECT, MTE_SYNC_ERR),
+	"Check buffer correctness by byte with sync err mode and mmap/mprotect memory\n");
+	evaluate_test(check_buffer_by_byte(USE_MPROTECT, MTE_ASYNC_ERR),
+	"Check buffer correctness by byte with async err mode and mmap/mprotect memory\n");
+
+	/* Check buffer underflow with underflow size as 16 */
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_SYNC_ERR, MT_GRANULE_SIZE),
+	"Check buffer write underflow by byte with sync mode and mmap memory\n");
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, MT_GRANULE_SIZE),
+	"Check buffer write underflow by byte with async mode and mmap memory\n");
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_NONE_ERR, MT_GRANULE_SIZE),
+	"Check buffer write underflow by byte with tag check fault ignore and mmap memory\n");
+
+	/* Check buffer underflow with underflow size as page size */
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_SYNC_ERR, page_size),
+	"Check buffer write underflow by byte with sync mode and mmap memory\n");
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, page_size),
+	"Check buffer write underflow by byte with async mode and mmap memory\n");
+	evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_NONE_ERR, page_size),
+	"Check buffer write underflow by byte with tag check fault ignore and mmap memory\n");
+
+	/* Check buffer overflow with overflow size as 16 */
+	evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_SYNC_ERR, MT_GRANULE_SIZE),
+	"Check buffer write overflow by byte with sync mode and mmap memory\n");
+	evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, MT_GRANULE_SIZE),
+	"Check buffer write overflow by byte with async mode and mmap memory\n");
+	evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_NONE_ERR, MT_GRANULE_SIZE),
+	"Check buffer write overflow by byte with tag fault ignore mode and mmap memory\n");
+
+	/* Buffer by block tests */
+	evaluate_test(check_buffer_by_block(USE_MMAP, MTE_SYNC_ERR),
+	"Check buffer write correctness by block with sync mode and mmap memory\n");
+	evaluate_test(check_buffer_by_block(USE_MMAP, MTE_ASYNC_ERR),
+	"Check buffer write correctness by block with async mode and mmap memory\n");
+	evaluate_test(check_buffer_by_block(USE_MMAP, MTE_NONE_ERR),
+	"Check buffer write correctness by block with tag fault ignore and mmap memory\n");
+
+	/* Initial tags are supposed to be 0 */
+	evaluate_test(check_memory_initial_tags(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE),
+	"Check initial tags with private mapping, sync error mode and mmap memory\n");
+	evaluate_test(check_memory_initial_tags(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE),
+	"Check initial tags with private mapping, sync error mode and mmap/mprotect memory\n");
+	evaluate_test(check_memory_initial_tags(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED),
+	"Check initial tags with shared mapping, sync error mode and mmap memory\n");
+	evaluate_test(check_memory_initial_tags(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED),
+	"Check initial tags with shared mapping, sync error mode and mmap/mprotect memory\n");
+
+	mte_restore_setup();
+	ksft_print_cnts();
+	return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL;
+}
diff --git a/tools/testing/selftests/arm64/mte/check_child_memory.c b/tools/testing/selftests/arm64/mte/check_child_memory.c
new file mode 100644
index 000000000000..97bebdecd29e
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/check_child_memory.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 ARM Limited
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ucontext.h>
+#include <sys/wait.h>
+
+#include "kselftest.h"
+#include "mte_common_util.h"
+#include "mte_def.h"
+
+#define BUFFER_SIZE		(5 * MT_GRANULE_SIZE)
+#define RUNS			(MT_TAG_COUNT)
+#define UNDERFLOW		MT_GRANULE_SIZE
+#define OVERFLOW		MT_GRANULE_SIZE
+
+static size_t page_size;
+static int sizes[] = {
+	1, 537, 989, 1269, MT_GRANULE_SIZE - 1, MT_GRANULE_SIZE,
+	/* page size - 1*/ 0, /* page_size */ 0, /* page size + 1 */ 0
+};
+
+static int check_child_tag_inheritance(char *ptr, int size, int mode)
+{
+	int i, parent_tag, child_tag, fault, child_status;
+	pid_t child;
+
+	parent_tag = MT_FETCH_TAG((uintptr_t)ptr);
+	fault = 0;
+
+	child = fork();
+	if (child == -1) {
+		ksft_print_msg("FAIL: child process creation\n");
+		return KSFT_FAIL;
+	} else if (child == 0) {
+		mte_initialize_current_context(mode, (uintptr_t)ptr, size);
+		/* Do copy on write */
+		memset(ptr, '1', size);
+		mte_wait_after_trig();
+		if (cur_mte_cxt.fault_valid == true) {
+			fault = 1;
+			goto check_child_tag_inheritance_err;
+		}
+		for (i = 0 ; i < size ; i += MT_GRANULE_SIZE) {
+			child_tag = MT_FETCH_TAG((uintptr_t)(mte_get_tag_address(ptr + i)));
+			if (parent_tag != child_tag) {
+				ksft_print_msg("FAIL: child mte tag mismatch\n");
+				fault = 1;
+				goto check_child_tag_inheritance_err;
+			}
+		}
+		mte_initialize_current_context(mode, (uintptr_t)ptr, -UNDERFLOW);
+		memset(ptr - UNDERFLOW, '2', UNDERFLOW);
+		mte_wait_after_trig();
+		if (cur_mte_cxt.fault_valid == false) {
+			fault = 1;
+			goto check_child_tag_inheritance_err;
+		}
+		mte_initialize_current_context(mode, (uintptr_t)ptr, size + OVERFLOW);
+		memset(ptr + size, '3', OVERFLOW);
+		mte_wait_after_trig();
+		if (cur_mte_cxt.fault_valid == false) {
+			fault = 1;
+			goto check_child_tag_inheritance_err;
+		}
+check_child_tag_inheritance_err:
+		_exit(fault);
+	}
+	/* Wait for child process to terminate */
+	wait(&child_status);
+	if (WIFEXITED(child_status))
+		fault = WEXITSTATUS(child_status);
+	else
+		fault = 1;
+	return (fault) ? KSFT_FAIL : KSFT_PASS;
+}
+
+static int check_child_memory_mapping(int mem_type, int mode, int mapping)
+{
+	char *ptr;
+	int run, result;
+	int item = sizeof(sizes)/sizeof(int);
+
+	item = sizeof(sizes)/sizeof(int);
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	for (run = 0; run < item; run++) {
+		ptr = (char *)mte_allocate_memory_tag_range(sizes[run], mem_type, mapping,
+							    UNDERFLOW, OVERFLOW);
+		if (check_allocated_memory_range(ptr, sizes[run], mem_type,
+						 UNDERFLOW, OVERFLOW) != KSFT_PASS)
+			return KSFT_FAIL;
+		result = check_child_tag_inheritance(ptr, sizes[run], mode);
+		mte_free_memory_tag_range((void *)ptr, sizes[run], mem_type, UNDERFLOW, OVERFLOW);
+		if (result == KSFT_FAIL)
+			return result;
+	}
+	return KSFT_PASS;
+}
+
+static int check_child_file_mapping(int mem_type, int mode, int mapping)
+{
+	char *ptr, *map_ptr;
+	int run, fd, map_size, result = KSFT_PASS;
+	int total = sizeof(sizes)/sizeof(int);
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	for (run = 0; run < total; run++) {
+		fd = create_temp_file();
+		if (fd == -1)
+			return KSFT_FAIL;
+
+		map_size = sizes[run] + OVERFLOW + UNDERFLOW;
+		map_ptr = (char *)mte_allocate_file_memory(map_size, mem_type, mapping, false, fd);
+		if (check_allocated_memory(map_ptr, map_size, mem_type, false) != KSFT_PASS) {
+			close(fd);
+			return KSFT_FAIL;
+		}
+		ptr = map_ptr + UNDERFLOW;
+		mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[run]);
+		/* Only mte enabled memory will allow tag insertion */
+		ptr = mte_insert_tags((void *)ptr, sizes[run]);
+		if (!ptr || cur_mte_cxt.fault_valid == true) {
+			ksft_print_msg("FAIL: Insert tags on file based memory\n");
+			munmap((void *)map_ptr, map_size);
+			close(fd);
+			return KSFT_FAIL;
+		}
+		result = check_child_tag_inheritance(ptr, sizes[run], mode);
+		mte_clear_tags((void *)ptr, sizes[run]);
+		munmap((void *)map_ptr, map_size);
+		close(fd);
+		if (result != KSFT_PASS)
+			return KSFT_FAIL;
+	}
+	return KSFT_PASS;
+}
+
+int main(int argc, char *argv[])
+{
+	int err;
+	int item = sizeof(sizes)/sizeof(int);
+
+	page_size = getpagesize();
+	if (!page_size) {
+		ksft_print_msg("ERR: Unable to get page size\n");
+		return KSFT_FAIL;
+	}
+	sizes[item - 3] = page_size - 1;
+	sizes[item - 2] = page_size;
+	sizes[item - 1] = page_size + 1;
+
+	err = mte_default_setup();
+	if (err)
+		return err;
+
+	/* Register SIGSEGV handler */
+	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGBUS, mte_default_handler);
+
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE),
+		"Check child anonymous memory with private mapping, precise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED),
+		"Check child anonymous memory with shared mapping, precise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE),
+		"Check child anonymous memory with private mapping, imprecise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED),
+		"Check child anonymous memory with shared mapping, imprecise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE),
+		"Check child anonymous memory with private mapping, precise mode and mmap/mprotect memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED),
+		"Check child anonymous memory with shared mapping, precise mode and mmap/mprotect memory\n");
+
+	evaluate_test(check_child_file_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE),
+		"Check child file memory with private mapping, precise mode and mmap memory\n");
+	evaluate_test(check_child_file_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED),
+		"Check child file memory with shared mapping, precise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE),
+		"Check child file memory with private mapping, imprecise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED),
+		"Check child file memory with shared mapping, imprecise mode and mmap memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE),
+		"Check child file memory with private mapping, precise mode and mmap/mprotect memory\n");
+	evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED),
+		"Check child file memory with shared mapping, precise mode and mmap/mprotect memory\n");
+
+	mte_restore_setup();
+	ksft_print_cnts();
+	return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL;
+}
diff --git a/tools/testing/selftests/arm64/mte/check_ksm_options.c b/tools/testing/selftests/arm64/mte/check_ksm_options.c
new file mode 100644
index 000000000000..bc41ae630c86
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/check_ksm_options.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 ARM Limited
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+
+#include "kselftest.h"
+#include "mte_common_util.h"
+#include "mte_def.h"
+
+#define TEST_UNIT	10
+#define PATH_KSM	"/sys/kernel/mm/ksm/"
+#define MAX_LOOP	4
+
+static size_t page_sz;
+static unsigned long ksm_sysfs[5];
+
+static unsigned long read_sysfs(char *str)
+{
+	FILE *f;
+	unsigned long val = 0;
+
+	f = fopen(str, "r");
+	if (!f) {
+		ksft_print_msg("ERR: missing %s\n", str);
+		return 0;
+	}
+	fscanf(f, "%lu", &val);
+	fclose(f);
+	return val;
+}
+
+static void write_sysfs(char *str, unsigned long val)
+{
+	FILE *f;
+
+	f = fopen(str, "w");
+	if (!f) {
+		ksft_print_msg("ERR: missing %s\n", str);
+		return;
+	}
+	fprintf(f, "%lu", val);
+	fclose(f);
+}
+
+static void mte_ksm_setup(void)
+{
+	ksm_sysfs[0] = read_sysfs(PATH_KSM "merge_across_nodes");
+	write_sysfs(PATH_KSM "merge_across_nodes", 1);
+	ksm_sysfs[1] = read_sysfs(PATH_KSM "sleep_millisecs");
+	write_sysfs(PATH_KSM "sleep_millisecs", 0);
+	ksm_sysfs[2] = read_sysfs(PATH_KSM "run");
+	write_sysfs(PATH_KSM "run", 1);
+	ksm_sysfs[3] = read_sysfs(PATH_KSM "max_page_sharing");
+	write_sysfs(PATH_KSM "max_page_sharing", ksm_sysfs[3] + TEST_UNIT);
+	ksm_sysfs[4] = read_sysfs(PATH_KSM "pages_to_scan");
+	write_sysfs(PATH_KSM "pages_to_scan", ksm_sysfs[4] + TEST_UNIT);
+}
+
+static void mte_ksm_restore(void)
+{
+	write_sysfs(PATH_KSM "merge_across_nodes", ksm_sysfs[0]);
+	write_sysfs(PATH_KSM "sleep_millisecs", ksm_sysfs[1]);
+	write_sysfs(PATH_KSM "run", ksm_sysfs[2]);
+	write_sysfs(PATH_KSM "max_page_sharing", ksm_sysfs[3]);
+	write_sysfs(PATH_KSM "pages_to_scan", ksm_sysfs[4]);
+}
+
+static void mte_ksm_scan(void)
+{
+	int cur_count = read_sysfs(PATH_KSM "full_scans");
+	int scan_count = cur_count + 1;
+	int max_loop_count = MAX_LOOP;
+
+	while ((cur_count < scan_count) && max_loop_count) {
+		sleep(1);
+		cur_count = read_sysfs(PATH_KSM "full_scans");
+		max_loop_count--;
+	}
+#ifdef DEBUG
+	ksft_print_msg("INFO: pages_shared=%lu pages_sharing=%lu\n",
+			read_sysfs(PATH_KSM "pages_shared"),
+			read_sysfs(PATH_KSM "pages_sharing"));
+#endif
+}
+
+static int check_madvise_options(int mem_type, int mode, int mapping)
+{
+	char *ptr;
+	int err, ret;
+
+	err = KSFT_FAIL;
+	if (access(PATH_KSM, F_OK) == -1) {
+		ksft_print_msg("ERR: Kernel KSM config not enabled\n");
+		return err;
+	}
+
+	mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG);
+	ptr = mte_allocate_memory(TEST_UNIT * page_sz, mem_type, mapping, true);
+	if (check_allocated_memory(ptr, TEST_UNIT * page_sz, mem_type, false) != KSFT_PASS)
+		return KSFT_FAIL;
+
+	/* Insert same data in all the pages */
+	memset(ptr, 'A', TEST_UNIT * page_sz);
+	ret = madvise(ptr, TEST_UNIT * page_sz, MADV_MERGEABLE);
+	if (ret) {
+		ksft_print_msg("ERR: madvise failed to set MADV_UNMERGEABLE\n");
+		goto madvise_err;
+	}
+	mte_ksm_scan();
+	/* Tagged pages should not merge */
+	if ((read_sysfs(PATH_KSM "pages_shared") < 1) ||
+	    (read_sysfs(PATH_KSM "pages_sharing") < (TEST_UNIT - 1)))
+		err = KSFT_PASS;
+madvise_err:
+	mte_free_memory(ptr, TEST_UNIT * page_sz, mem_type, true);
+	return err;
+}
+
+int main(int argc, char *argv[])
+{
+	int err;
+
+	err = mte_default_setup();
+	if (err)
+		return err;
+	page_sz = getpagesize();
+	if (!page_sz) {
+		ksft_print_msg("ERR: Unable to get page size\n");
+		return KSFT_FAIL;
+	}
+	/* Register signal handlers */
+	mte_register_signal(SIGBUS, mte_default_handler);
+	mte_register_signal(SIGSEGV, mte_default_handler);
+	/* Enable KSM */
+	mte_ksm_setup();
+
+	evaluate_test(check_madvise_options(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE),
+		"Check KSM mte page merge for private mapping, sync mode and mmap memory\n");
+	evaluate_test(check_madvise_options(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE),
+		"Check KSM mte page merge for private mapping, async mode and mmap memory\n");
+	evaluate_test(check_madvise_options(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED),
+		"Check KSM mte page merge for shared mapping, sync mode and mmap memory\n");
+	evaluate_test(check_madvise_options(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED),
+		"Check KSM mte page merge for shared mapping, async mode and mmap memory\n");
+
+	mte_ksm_restore();
+	mte_restore_setup();
+	ksft_print_cnts();
+	return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL;
+}
diff --git a/tools/testing/selftests/arm64/mte/check_mmap_options.c b/tools/testing/selftests/arm64/mte/check_mmap_options.c
new file mode 100644
index 000000000000..33b13b86199b
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/check_mmap_options.c
@@ -0,0 +1,262 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 ARM Limited
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "kselftest.h"
+#include "mte_common_util.h"
+#include "mte_def.h"
+
+#define RUNS			(MT_TAG_COUNT)
+#define UNDERFLOW		MT_GRANULE_SIZE
+#define OVERFLOW		MT_GRANULE_SIZE
+#define TAG_CHECK_ON		0
+#define TAG_CHECK_OFF		1
+
+static size_t page_size;
+static int sizes[] = {
+	1, 537, 989, 1269, MT_GRANULE_SIZE - 1, MT_GRANULE_SIZE,
+	/* page size - 1*/ 0, /* page_size */ 0, /* page size + 1 */ 0
+};
+
+static int check_mte_memory(char *ptr, int size, int mode, int tag_check)
+{
+	mte_initialize_current_context(mode, (uintptr_t)ptr, size);