Merge branch 'next' into for-linus

1 files changed, 1748 insertions, 0 deletions

diff --git a/arch/arm/kernel/kprobes-test.c b/arch/arm/kernel/kprobes-test.c
new file mode 100644
index 000000000000..e17cdd6d90d8
--- /dev/null
+++ b/arch/arm/kernel/kprobes-test.c
@@ -0,0 +1,1748 @@
+/*
+ * arch/arm/kernel/kprobes-test.c
+ *
+ * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This file contains test code for ARM kprobes.
+ *
+ * The top level function run_all_tests() executes tests for all of the
+ * supported instruction sets: ARM, 16-bit Thumb, and 32-bit Thumb. These tests
+ * fall into two categories; run_api_tests() checks basic functionality of the
+ * kprobes API, and run_test_cases() is a comprehensive test for kprobes
+ * instruction decoding and simulation.
+ *
+ * run_test_cases() first checks the kprobes decoding table for self consistency
+ * (using table_test()) then executes a series of test cases for each of the CPU
+ * instruction forms. coverage_start() and coverage_end() are used to verify
+ * that these test cases cover all of the possible combinations of instructions
+ * described by the kprobes decoding tables.
+ *
+ * The individual test cases are in kprobes-test-arm.c and kprobes-test-thumb.c
+ * which use the macros defined in kprobes-test.h. The rest of this
+ * documentation will describe the operation of the framework used by these
+ * test cases.
+ */
+
+/*
+ * TESTING METHODOLOGY
+ * -------------------
+ *
+ * The methodology used to test an ARM instruction 'test_insn' is to use
+ * inline assembler like:
+ *
+ * test_before: nop
+ * test_case:	test_insn
+ * test_after:	nop
+ *
+ * When the test case is run a kprobe is placed of each nop. The
+ * post-handler of the test_before probe is used to modify the saved CPU
+ * register context to that which we require for the test case. The
+ * pre-handler of the of the test_after probe saves a copy of the CPU
+ * register context. In this way we can execute test_insn with a specific
+ * register context and see the results afterwards.
+ *
+ * To actually test the kprobes instruction emulation we perform the above
+ * step a second time but with an additional kprobe on the test_case
+ * instruction itself. If the emulation is accurate then the results seen
+ * by the test_after probe will be identical to the first run which didn't
+ * have a probe on test_case.
+ *
+ * Each test case is run several times with a variety of variations in the
+ * flags value of stored in CPSR, and for Thumb code, different ITState.
+ *
+ * For instructions which can modify PC, a second test_after probe is used
+ * like this:
+ *
+ * test_before: nop
+ * test_case:	test_insn
+ * test_after:	nop
+ *		b test_done
+ * test_after2: nop
+ * test_done:
+ *
+ * The test case is constructed such that test_insn branches to
+ * test_after2, or, if testing a conditional instruction, it may just
+ * continue to test_after. The probes inserted at both locations let us
+ * determine which happened. A similar approach is used for testing
+ * backwards branches...
+ *
+ *		b test_before
+ *		b test_done  @ helps to cope with off by 1 branches
+ * test_after2: nop
+ *		b test_done
+ * test_before: nop
+ * test_case:	test_insn
+ * test_after:	nop
+ * test_done:
+ *
+ * The macros used to generate the assembler instructions describe above
+ * are TEST_INSTRUCTION, TEST_BRANCH_F (branch forwards) and TEST_BRANCH_B
+ * (branch backwards). In these, the local variables numbered 1, 50, 2 and
+ * 99 represent: test_before, test_case, test_after2 and test_done.
+ *
+ * FRAMEWORK
+ * ---------
+ *
+ * Each test case is wrapped between the pair of macros TESTCASE_START and
+ * TESTCASE_END. As well as performing the inline assembler boilerplate,
+ * these call out to the kprobes_test_case_start() and
+ * kprobes_test_case_end() functions which drive the execution of the test
+ * case. The specific arguments to use for each test case are stored as
+ * inline data constructed using the various TEST_ARG_* macros. Putting
+ * this all together, a simple test case may look like:
+ *
+ *	TESTCASE_START("Testing mov r0, r7")
+ *	TEST_ARG_REG(7, 0x12345678) // Set r7=0x12345678
+ *	TEST_ARG_END("")
+ *	TEST_INSTRUCTION("mov r0, r7")
+ *	TESTCASE_END
+ *
+ * Note, in practice the single convenience macro TEST_R would be used for this
+ * instead.
+ *
+ * The above would expand to assembler looking something like:
+ *
+ *	@ TESTCASE_START
+ *	bl	__kprobes_test_case_start
+ *	@ start of inline data...
+ *	.ascii "mov r0, r7"	@ text title for test case
+ *	.byte	0
+ *	.align	2
+ *
+ *	@ TEST_ARG_REG
+ *	.byte	ARG_TYPE_REG
+ *	.byte	7
+ *	.short	0
+ *	.word	0x1234567
+ *
+ *	@ TEST_ARG_END
+ *	.byte	ARG_TYPE_END
+ *	.byte	TEST_ISA	@ flags, including ISA being tested
+ *	.short	50f-0f		@ offset of 'test_before'
+ *	.short	2f-0f		@ offset of 'test_after2' (if relevent)
+ *	.short	99f-0f		@ offset of 'test_done'
+ *	@ start of test case code...
+ *	0:
+ *	.code	TEST_ISA	@ switch to ISA being tested
+ *
+ *	@ TEST_INSTRUCTION
+ *	50:	nop		@ location for 'test_before' probe
+ *	1:	mov r0, r7	@ the test case instruction 'test_insn'
+ *		nop		@ location for 'test_after' probe
+ *
+ *	// TESTCASE_END
+ *	2:
+ *	99:	bl __kprobes_test_case_end_##TEST_ISA
+ *	.code	NONMAL_ISA
+ *
+ * When the above is execute the following happens...
+ *
+ * __kprobes_test_case_start() is an assembler wrapper which sets up space
+ * for a stack buffer and calls the C function kprobes_test_case_start().
+ * This C function will do some initial processing of the inline data and
+ * setup some global state. It then inserts the test_before and test_after
+ * kprobes and returns a value which causes the assembler wrapper to jump
+ * to the start of the test case code, (local label '0').
+ *
+ * When the test case code executes, the test_before probe will be hit and
+ * test_before_post_handler will call setup_test_context(). This fills the
+ * stack buffer and CPU registers with a test pattern and then processes
+ * the test case arguments. In our example there is one TEST_ARG_REG which
+ * indicates that R7 should be loaded with the value 0x12345678.
+ *
+ * When the test_before probe ends, the test case continues and executes
+ * the "mov r0, r7" instruction. It then hits the test_after probe and the
+ * pre-handler for this (test_after_pre_handler) will save a copy of the
+ * CPU register context. This should now have R0 holding the same value as
+ * R7.
+ *
+ * Finally we get to the call to __kprobes_test_case_end_{32,16}. This is
+ * an assembler wrapper which switches back to the ISA used by the test
+ * code and calls the C function kprobes_test_case_end().
+ *
+ * For each run through the test case, test_case_run_count is incremented
+ * by one. For even runs, kprobes_test_case_end() saves a copy of the
+ * register and stack buffer contents from the test case just run. It then
+ * inserts a kprobe on the test case instruction 'test_insn' and returns a
+ * value to cause the test case code to be re-run.
+ *
+ * For odd numbered runs, kprobes_test_case_end() compares the register and
+ * stack buffer contents to those that were saved on the previous even
+ * numbered run (the one without the kprobe on test_insn). These should be
+ * the same if the kprobe instruction simulation routine is correct.
+ *
+ * The pair of test case runs is repeated with different combinations of
+ * flag values in CPSR and, for Thumb, different ITState. This is
+ * controlled by test_context_cpsr().
+ *
+ * BUILDING TEST CASES
+ * -------------------
+ *
+ *
+ * As an aid to building test cases, the stack buffer is initialised with
+ * some special values:
+ *
+ *   [SP+13*4]	Contains SP+120. This can be used to test instructions
+ *		which load a value into SP.
+ *
+ *   [SP+15*4]	When testing branching instructions using TEST_BRANCH_{F,B},
+ *		this holds the target address of the branch, 'test_after2'.
+ *		This can be used to test instructions which load a PC value
+ *		from memory.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kprobes.h>
+
+#include "kprobes.h"
+#include "kprobes-test.h"
+
+
+#define BENCHMARKING	1
+
+
+/*
+ * Test basic API
+ */
+
+static bool test_regs_ok;
+static int test_func_instance;
+static int pre_handler_called;
+static int post_handler_called;
+static int jprobe_func_called;
+static int kretprobe_handler_called;
+
+#define FUNC_ARG1 0x12345678
+#define FUNC_ARG2 0xabcdef
+
+
+#ifndef CONFIG_THUMB2_KERNEL
+
+long arm_func(long r0, long r1);
+
+static void __used __naked __arm_kprobes_test_func(void)
+{
+	__asm__ __volatile__ (
+		".arm					\n\t"
+		".type arm_func, %%function		\n\t"
+		"arm_func:				\n\t"
+		"adds	r0, r0, r1			\n\t"
+		"bx	lr				\n\t"
+		".code "NORMAL_ISA	 /* Back to Thumb if necessary */
+		: : : "r0", "r1", "cc"
+	);
+}
+
+#else /* CONFIG_THUMB2_KERNEL */
+
+long thumb16_func(long r0, long r1);
+long thumb32even_func(long r0, long r1);
+long thumb32odd_func(long r0, long r1);
+
+static void __used __naked __thumb_kprobes_test_funcs(void)
+{
+	__asm__ __volatile__ (
+		".type thumb16_func, %%function		\n\t"
+		"thumb16_func:				\n\t"
+		"adds.n	r0, r0, r1			\n\t"
+		"bx	lr				\n\t"
+
+		".align					\n\t"
+		".type thumb32even_func, %%function	\n\t"
+		"thumb32even_func:			\n\t"
+		"adds.w	r0, r0, r1			\n\t"
+		"bx	lr				\n\t"
+
+		".align					\n\t"
+		"nop.n					\n\t"
+		".type thumb32odd_func, %%function	\n\t"
+		"thumb32odd_func:			\n\t"
+		"adds.w	r0, r0, r1			\n\t"
+		"bx	lr				\n\t"
+
+		: : : "r0", "r1", "cc"
+	);
+}
+
+#endif /* CONFIG_THUMB2_KERNEL */
+
+
+static int call_test_func(long (*func)(long, long), bool check_test_regs)
+{
+	long ret;
+
+	++test_func_instance;
+	test_regs_ok = false;
+
+	ret = (*func)(FUNC_ARG1, FUNC_ARG2);
+	if (ret != FUNC_ARG1 + FUNC_ARG2) {
+		pr_err("FAIL: call_test_func: func returned %lx\n", ret);
+		return false;
+	}
+
+	if (check_test_regs && !test_regs_ok) {
+		pr_err("FAIL: test regs not OK\n");
+		return false;
+	}
+
+	return true;
+}
+
+static int __kprobes pre_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	pre_handler_called = test_func_instance;
+	if (regs->ARM_r0 == FUNC_ARG1 && regs->ARM_r1 == FUNC_ARG2)
+		test_regs_ok = true;
+	return 0;
+}
+
+static void __kprobes post_handler(struct kprobe *p, struct pt_regs *regs,
+				unsigned long flags)
+{
+	post_handler_called = test_func_instance;
+	if (regs->ARM_r0 != FUNC_ARG1 + FUNC_ARG2 || regs->ARM_r1 != FUNC_ARG2)
+		test_regs_ok = false;
+}
+
+static struct kprobe the_kprobe = {
+	.addr		= 0,
+	.pre_handler	= pre_handler,
+	.post_handler	= post_handler
+};
+
+static int test_kprobe(long (*func)(long, long))
+{
+	int ret;
+
+	the_kprobe.addr = (kprobe_opcode_t *)func;
+	ret = register_kprobe(&the_kprobe);
+	if (ret < 0) {
+		pr_err("FAIL: register_kprobe failed with %d\n", ret);
+		return ret;
+	}
+
+	ret = call_test_func(func, true);
+
+	unregister_kprobe(&the_kprobe);
+	the_kprobe.flags = 0; /* Clear disable flag to allow reuse */
+
+	if (!ret)
+		return -EINVAL;
+	if (pre_handler_called != test_func_instance) {
+		pr_err("FAIL: kprobe pre_handler not called\n");
+		return -EINVAL;
+	}
+	if (post_handler_called != test_func_instance) {
+		pr_err("FAIL: kprobe post_handler not called\n");
+		return -EINVAL;
+	}
+	if (!call_test_func(func, false))
+		return -EINVAL;
+	if (pre_handler_called == test_func_instance ||
+				post_handler_called == test_func_instance) {
+		pr_err("FAIL: probe called after unregistering\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void __kprobes jprobe_func(long r0, long r1)
+{
+	jprobe_func_called = test_func_instance;
+	if (r0 == FUNC_ARG1 && r1 == FUNC_ARG2)
+		test_regs_ok = true;
+	jprobe_return();
+}
+
+static struct jprobe the_jprobe = {
+	.entry		= jprobe_func,
+};
+
+static int test_jprobe(long (*func)(long, long))
+{
+	int ret;
+
+	the_jprobe.kp.addr = (kprobe_opcode_t *)func;
+	ret = register_jprobe(&the_jprobe);
+	if (ret < 0) {
+		pr_err("FAIL: register_jprobe failed with %d\n", ret);
+		return ret;
+	}
+
+	ret = call_test_func(func, true);
+
+	unregister_jprobe(&the_jprobe);
+	the_jprobe.kp.flags = 0; /* Clear disable flag to allow reuse */
+
+	if (!ret)
+		return -EINVAL;
+	if (jprobe_func_called != test_func_instance) {
+		pr_err("FAIL: jprobe handler function not called\n");
+		return -EINVAL;
+	}
+	if (!call_test_func(func, false))
+		return -EINVAL;
+	if (jprobe_func_called == test_func_instance) {
+		pr_err("FAIL: probe called after unregistering\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __kprobes
+kretprobe_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
+{
+	kretprobe_handler_called = test_func_instance;
+	if (regs_return_value(regs) == FUNC_ARG1 + FUNC_ARG2)
+		test_regs_ok = true;
+	return 0;
+}
+
+static struct kretprobe the_kretprobe = {
+	.handler	= kretprobe_handler,
+};
+
+static int test_kretprobe(long (*func)(long, long))
+{
+	int ret;
+
+	the_kretprobe.kp.addr = (kprobe_opcode_t *)func;
+	ret = register_kretprobe(&the_kretprobe);
+	if (ret < 0) {
+		pr_err("FAIL: register_kretprobe failed with %d\n", ret);
+		return ret;
+	}
+
+	ret = call_test_func(func, true);
+
+	unregister_kretprobe(&the_kretprobe);
+	the_kretprobe.kp.flags = 0; /* Clear disable flag to allow reuse */
+
+	if (!ret)
+		return -EINVAL;
+	if (kretprobe_handler_called != test_func_instance) {
+		pr_err("FAIL: kretprobe handler not called\n");
+		return -EINVAL;
+	}
+	if (!call_test_func(func, false))
+		return -EINVAL;
+	if (jprobe_func_called == test_func_instance) {
+		pr_err("FAIL: kretprobe called after unregistering\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int run_api_tests(long (*func)(long, long))
+{
+	int ret;
+
+	pr_info("    kprobe\n");
+	ret = test_kprobe(func);
+	if (ret < 0)
+		return ret;
+
+	pr_info("    jprobe\n");
+	ret = test_jprobe(func);
+	if (ret < 0)
+		return ret;
+
+	pr_info("    kretprobe\n");
+	ret = test_kretprobe(func);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+
+/*
+ * Benchmarking
+ */
+
+#if BENCHMARKING
+
+static void __naked benchmark_nop(void)
+{
+	__asm__ __volatile__ (
+		"nop		\n\t"
+		"bx	lr"
+	);
+}
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define wide ".w"
+#else
+#define wide
+#endif
+
+static void __naked benchmark_pushpop1(void)
+{
+	__asm__ __volatile__ (
+		"stmdb"wide"	sp!, {r3-r11,lr}  \n\t"
+		"ldmia"wide"	sp!, {r3-r11,pc}"
+	);
+}
+
+static void __naked benchmark_pushpop2(void)
+{
+	__asm__ __volatile__ (
+		"stmdb"wide"	sp!, {r0-r8,lr}  \n\t"
+		"ldmia"wide"	sp!, {r0-r8,pc}"
+	);
+}
+
+static void __naked benchmark_pushpop3(void)
+{
+	__asm__ __volatile__ (
+		"stmdb"wide"	sp!, {r4,lr}  \n\t"
+		"ldmia"wide"	sp!, {r4,pc}"
+	);
+}
+
+static void __naked benchmark_pushpop4(void)
+{
+	__asm__ __volatile__ (
+		"stmdb"wide"	sp!, {r0,lr}  \n\t"
+		"ldmia"wide"	sp!, {r0,pc}"
+	);
+}
+
+
+#ifdef CONFIG_THUMB2_KERNEL
+
+static void __naked benchmark_pushpop_thumb(void)
+{
+	__asm__ __volatile__ (
+		"push.n	{r0-r7,lr}  \n\t"
+		"pop.n	{r0-r7,pc}"
+	);
+}
+
+#endif
+
+static int __kprobes
+benchmark_pre_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	return 0;
+}
+
+static int benchmark(void(*fn)(void))
+{
+	unsigned n, i, t, t0;
+
+	for (n = 1000; ; n *= 2) {
+		t0 = sched_clock();
+		for (i = n; i > 0; --i)
+			fn();
+		t = sched_clock() - t0;
+		if (t >= 250000000)
+			break; /* Stop once we took more than 0.25 seconds */
+	}
+	return t / n; /* Time for one iteration in nanoseconds */
+};
+
+static int kprobe_benchmark(void(*fn)(void), unsigned offset)
+{
+	struct kprobe k = {
+		.addr		= (kprobe_opcode_t *)((uintptr_t)fn + offset),
+		.pre_handler	= benchmark_pre_handler,
+	};
+
+	int ret = register_kprobe(&k);
+	if (ret < 0) {
+		pr_err("FAIL: register_kprobe failed with %d\n", ret);
+		return ret;
+	}
+
+	ret = benchmark(fn);
+
+	unregister_kprobe(&k);
+	return ret;
+};
+
+struct benchmarks {
+	void		(*fn)(void);
+	unsigned	offset;
+	const char	*title;
+};
+
+static int run_benchmarks(void)
+{
+	int ret;
+	struct benchmarks list[] = {
+		{&benchmark_nop, 0, "nop"},
+		/*
+		 * benchmark_pushpop{1,3} will have the optimised
+		 * instruction emulation, whilst benchmark_pushpop{2,4} will
+		 * be the equivalent unoptimised instructions.
+		 */
+		{&benchmark_pushpop1, 0, "stmdb	sp!, {r3-r11,lr}"},
+		{&benchmark_pushpop1, 4, "ldmia	sp!, {r3-r11,pc}"},
+		{&benchmark_pushpop2, 0, "stmdb	sp!, {r0-r8,lr}"},
+		{&benchmark_pushpop2, 4, "ldmia	sp!, {r0-r8,pc}"},
+		{&benchmark_pushpop3, 0, "stmdb	sp!, {r4,lr}"},
+		{&benchmark_pushpop3, 4, "ldmia	sp!, {r4,pc}"},
+		{&benchmark_pushpop4, 0, "stmdb	sp!, {r0,lr}"},
+		{&benchmark_pushpop4, 4, "ldmia	sp!, {r0,pc}"},
+#ifdef CONFIG_THUMB2_KERNEL
+		{&benchmark_pushpop_thumb, 0, "push.n	{r0-r7,lr}"},
+		{&benchmark_pushpop_thumb, 2, "pop.n	{r0-r7,pc}"},
+#endif
+		{0}
+	};
+
+	struct benchmarks *b;
+	for (b = list; b->fn; ++b) {
+		ret = kprobe_benchmark(b->fn, b->offset);
+		if (ret < 0)
+			return ret;
+		pr_info("    %dns for kprobe %s\n", ret, b->title);
+	}
+
+	pr_info("\n");
+	return 0;
+}
+
+#endif /* BENCHMARKING */
+
+
+/*
+ * Decoding table self-consistency tests
+ */
+
+static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
+	[DECODE_TYPE_TABLE]	= sizeof(struct decode_table),
+	[DECODE_TYPE_CUSTOM]	= sizeof(struct decode_custom),
+	[DECODE_TYPE_SIMULATE]	= sizeof(struct decode_simulate),
+	[DECODE_TYPE_EMULATE]	= sizeof(struct decode_emulate),
+	[DECODE_TYPE_OR]	= sizeof(struct decode_or),
+	[DECODE_TYPE_REJECT]	= sizeof(struct decode_reject)
+};
+
+static int table_iter(const union decode_item *table,
+			int (*fn)(const struct decode_header *, void *),
+			void *args)
+{
+	const struct decode_header *h = (struct decode_header *)table;
+	int result;
+
+	for (;;) {
+		enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+
+		if (type == DECODE_TYPE_END)
+			return 0;
+
+		result = fn(h, args);
+		if (result)
+			return result;
+
+		h = (struct decode_header *)
+			((uintptr_t)h + decode_struct_sizes[type]);
+
+	}
+}
+
+static int table_test_fail(const struct decode_header *h, const char* message)
+{
+
+	pr_err("FAIL: kprobes test failure \"%s\" (mask %08x, value %08x)\n",
+					message, h->mask.bits, h->value.bits);
+	return -EINVAL;
+}
+
+struct table_test_args {
+	const union decode_item *root_table;
+	u32			parent_mask;
+	u32			parent_value;
+};
+
+static int table_test_fn(const struct decode_header *h, void *args)
+{
+	struct table_test_args *a = (struct table_test_args *)args;
+	enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+
+	if (h->value.bits & ~h->mask.bits)
+		return table_test_fail(h, "Match value has bits not in mask");
+
+	if ((h->mask.bits & a->parent_mask) != a->parent_mask)
+		return table_test_fail(h, "Mask has bits not in parent mask");
+
+	if ((h->value.bits ^ a->parent_value) & a->parent_mask)
+		return table_test_fail(h, "Value is inconsistent with parent");
+
+	if (type == DECODE_TYPE_TABLE) {
+		struct decode_table *d = (struct decode_table *)h;
+		struct table_test_args args2 = *a;
+		args2.parent_mask = h->mask.bits;
+		args2.parent_value = h->value.bits;
+		return table_iter(d->table.table, table_test_fn, &args2);
+	}
+
+	return 0;
+}
+
+static int table_test(const union decode_item *table)
+{
+	struct table_test_args args = {
+		.root_table	= table,
+		.parent_mask	= 0,
+		.parent_value	= 0
+	};
+	return table_iter(args.root_table, table_test_fn, &args);
+}
+
+
+/*
+ * Decoding table test coverage analysis
+ *
+ * coverage_start() builds a coverage_table which contains a list of
+ * coverage_entry's to match each entry in the specified kprobes instruction
+ * decoding table.
+ *
+ * When test cases are run, coverage_add() is called to process each case.
+ * This looks up the corresponding entry in the coverage_table and sets it as
+ * being matched, as well as clearing the regs flag appropriate for the test.
+ *
+ * After all test cases have been run, coverage_end() is called to check that
+ * all entries in coverage_table have been matched and that all regs flags are
+ * cleared. I.e. that all possible combinations of instructions described by
+ * the kprobes decoding tables have had a test case executed for them.
+ */
+
+bool coverage_fail;
+
+#define MAX_COVERAGE_ENTRIES 256
+
+struct coverage_entry {
+	const struct decode_header	*header;
+	unsigned			regs;
+	unsigned			nesting;
+	char				matched;
+};
+
+struct coverage_table {
+	struct coverage_entry	*base;
+	unsigned		num_entries;
+	unsigned		nesting;
+};
+
+struct coverage_table coverage;
+
+#define COVERAGE_ANY_REG	(1<<0)
+#define COVERAGE_SP		(1<<1)
+#define COVERAGE_PC		(1<<2)
+#define COVERAGE_PCWB		(1<<3)
+
+static const char coverage_register_lookup[16] = {
+	[REG_TYPE_ANY]		= COVERAGE_ANY_REG | COVERAGE_SP | COVERAGE_PC,
+	[REG_TYPE_SAMEAS16]	= COVERAGE_ANY_REG,
+	[REG_TYPE_SP]		= COVERAGE_SP,
+	[REG_TYPE_PC]		= COVERAGE_PC,
+	[REG_TYPE_NOSP]		= COVERAGE_ANY_REG | COVERAGE_SP,
+	[REG_TYPE_NOSPPC]	= COVERAGE_ANY_REG | COVERAGE_SP | COVERAGE_PC,
+	[REG_TYPE_NOPC]		= COVERAGE_ANY_REG | COVERAGE_PC,
+	[REG_TYPE_NOPCWB]	= COVERAGE_ANY_REG | COVERAGE_PC | COVERAGE_PCWB,
+	[REG_TYPE_NOPCX]	= COVERAGE_ANY_REG,
+	[REG_TYPE_NOSPPCX]	= COVERAGE_ANY_REG | COVERAGE_SP,
+};
+
+unsigned coverage_start_registers(const struct decode_header *h)
+{
+	unsigned regs = 0;
+	int i;
+	for (i = 0; i < 20; i += 4) {
+		int r = (h->type_regs.bits >> (DECODE_TYPE_BITS + i)) & 0xf;
+		regs |= coverage_register_lookup[r] << i;
+	}
+	return regs;
+}
+
+static int coverage_start_fn(const struct decode_header *h, void *args)
+{
+	struct coverage_table *coverage = (struct coverage_table *)args;
+	enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+	struct coverage_entry *entry = coverage->base + coverage->num_entries;
+
+	if (coverage->num_entries == MAX_COVERAGE_ENTRIES - 1) {
+		pr_err("FAIL: Out of space for test coverage data");
+		return -ENOMEM;
+	}
+
+	++coverage->num_entries;
+
+	entry->header = h;
+	entry->regs = coverage_start_registers(h);
+	entry->nesting = coverage->nesting;
+	entry->matched = false;
+
+	if (type == DECODE_TYPE_TABLE) {
+		struct decode_table *d = (struct decode_table *)h;
+		int ret;
+		++coverage->nesting;
+		ret = table_iter(d->table.table, coverage_start_fn, coverage);
+		--coverage->nesting;
+		return ret;
+	}
+
+	return 0;
+}
+
+static int coverage_start(const union decode_item *table)
+{
+	coverage.base = kmalloc(MAX_COVERAGE_ENTRIES *
+				sizeof(struct coverage_entry), GFP_KERNEL);
+	coverage.num_entries = 0;
+	coverage.nesting = 0;
+	return table_iter(table, coverage_start_fn, &coverage);
+}
+
+static void
+coverage_add_registers(struct coverage_entry *entry, kprobe_opcode_t insn)
+{
+	int regs = entry->header->type_regs.bits >> DECODE_TYPE_BITS;
+	int i;
+	for (i = 0; i < 20; i += 4) {
+		enum decode_reg_type reg_type = (regs >> i) & 0xf;
+		int reg = (insn >> i) & 0xf;
+		int flag;
+
+		if (!reg_type)
+			continue;
+
+		if (reg == 13)
+			flag = COVERAGE_SP;
+		else if (reg == 15)
+			flag = COVERAGE_PC;
+		else
+			flag = COVERAGE_ANY_REG;
+		entry->regs &= ~(flag << i);
+
+		switch (reg_type) {
+
+		case REG_TYPE_NONE:
+		case REG_TYPE_ANY:
+		case REG_TYPE_SAMEAS16:
+			break;
+
+		case REG_TYPE_SP:
+			if (reg != 13)
+				return;
+			break;
+
+		case REG_TYPE_PC:
+			if (reg != 15)
+				return;
+			break;
+
+		case REG_TYPE_NOSP:
+			if (reg == 13)
+				return;
+			break;
+
+		case REG_TYPE_NOSPPC:
+		case REG_TYPE_NOSPPCX:
+			if (reg == 13 || reg == 15)
+				return;
+			break;
+
+		case REG_TYPE_NOPCWB:
+			if (!is_writeback(insn))
+				break;
+			if (reg == 15) {
+				entry->regs &= ~(COVERAGE_PCWB << i);
+				return;
+			}
+			break;
+
+		case REG_TYPE_NOPC:
+		case REG_TYPE_NOPCX:
+			if (reg == 15)
+				return;
+			break;
+		}
+
+	}
+}
+
+static void coverage_add(kprobe_opcode_t insn)
+{
+	struct coverage_entry *entry = coverage.base;
+	struct coverage_entry *end = coverage.base + coverage.num_entries;
+	bool matched = false;
+	unsigned nesting = 0;
+
+	for (; entry < end; ++entry) {
+		const struct decode_header *h = entry->header;
+		enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+
+		if (entry->nesting > nesting)
+			continue; /* Skip sub-table we didn't match */
+
+		if (entry->nesting < nesting)
+			break; /* End of sub-table we were scanning */
+
+		if (!matched) {
+			if ((insn & h->mask.bits) != h->value.bits)
+				continue;
+			entry->matched = true;
+		}
+
+		switch (type) {
+
+		case DECODE_TYPE_TABLE:
+			++nesting;
+			break;
+
+		case DECODE_TYPE_CUSTOM:
+		case DECODE_TYPE_SIMULATE:
+		case DECODE_TYPE_EMULATE:
+			coverage_add_registers(entry, insn);
+			return;
+
+		case DECODE_TYPE_OR:
+			matched = true;
+			break;
+
+		case DECODE_TYPE_REJECT:
+		default:
+			return;
+		}
+
+	}
+}
+
+static void coverage_end(void)
+{
+	struct coverage_entry *entry = coverage.base;
+	struct coverage_entry *end = coverage.base + coverage.num_entries;
+
+	for (; entry < end; ++entry) {
+		u32 mask = entry->header->mask.bits;
+		u32 value = entry->header->value.bits;
+
+		if (entry->regs) {
+			pr_err("FAIL: Register test coverage missing for %08x %08x (%05x)\n",
+				mask, value, entry->regs);
+			coverage_fail = true;
+		}
+		if (!entry->matched) {
+			pr_err("FAIL: Test coverage entry missing for %08x %08x\n",
+				mask, value);
+			coverage_fail = true;
+		}
+	}
+
+	kfree(coverage.base);
+}
+
+
+/*
+ * Framework for instruction set test cases
+ */
+
+void __naked __kprobes_test_case_start(void)
+{
+	__asm__ __volatile__ (
+		"stmdb	sp!, {r4-r11}				\n\t"
+		"sub	sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t"
+		"bic	r0, lr, #1  @ r0 = inline title string	\n\t"
+		"mov	r1, sp					\n\t"
+		"bl	kprobes_test_case_start			\n\t"
+		"bx	r0					\n\t"
+	);
+}
+
+#ifndef CONFIG_THUMB2_KERNEL
+
+void __naked __kprobes_test_case_end_32(void)
+{
+	__asm__ __volatile__ (
+		"mov	r4, lr					\n\t"
+		"bl	kprobes_test_case_end			\n\t"
+		"cmp	r0, #0					\n\t"
+		"movne	pc, r0					\n\t"
+		"mov	r0, r4					\n\t"
+		"add	sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t"
+		"ldmia	sp!, {r4-r11}				\n\t"
+		"mov	pc, r0					\n\t"
+	);
+}
+
+#else /* CONFIG_THUMB2_KERNEL */
+
+void __naked __kprobes_test_case_end_16(void)
+{
+	__asm__ __volatile__ (
+		"mov	r4, lr					\n\t"
+		"bl	kprobes_test_case_end			\n\t"
+		"cmp	r0, #0					\n\t"
+		"bxne	r0					\n\t"
+		"mov	r0, r4					\n\t"
+		"add	sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t"
+		"ldmia	sp!, {r4-r11}				\n\t"
+		"bx	r0					\n\t"
+	);
+}
+
+void __naked __kprobes_test_case_end_32(void)
+{
+	__asm__ __volatile__ (
+		".arm						\n\t"
+		"orr	lr, lr, #1  @ will return to Thumb code	\n\t"
+		"ldr	pc, 1f					\n\t"
+		"1:						\n\t"
+		".word	__kprobes_test_case_end_16		\n\t"
+	);
+}
+
+#endif
+
+
+int kprobe_test_flags;
+int kprobe_test_cc_position;
+
+static int test_try_count;
+static int test_pass_count;
+static int test_fail_count;
+
+static struct pt_regs initial_regs;
+static struct pt_regs expected_regs;
+static struct pt_regs result_regs;
+
+static u32 expected_memory[TEST_MEMORY_SIZE/sizeof(u32)];
+
+static const char *current_title;
+static struct test_arg *current_args;
+static u32 *current_stack;
+static uintptr_t current_branch_target;
+
+static uintptr_t current_code_start;
+static kprobe_opcode_t current_instruction;
+
+
+#define TEST_CASE_PASSED -1
+#define TEST_CASE_FAILED -2
+
+static int test_case_run_count;
+static bool test_case_is_thumb;
+static int test_instance;
+
+/*
+ * We ignore the state of the imprecise abort disable flag (CPSR.A) because this
+ * can change randomly as the kernel doesn't take care to preserve or initialise
+ * this across context switches. Also, with Security Extentions, the flag may
+ * not be under control of the kernel; for this reason we ignore the state of
+ * the FIQ disable flag CPSR.F as well.
+ */
+#define PSR_IGNORE_BITS (PSR_A_BIT | PSR_F_BIT)
+
+static unsigned long test_check_cc(int cc, unsigned long cpsr)
+{
+	unsigned long temp;
+
+	switch (cc) {
+	case 0x0: /* eq */
+		return cpsr & PSR_Z_BIT;
+
+	case 0x1: /* ne */
+		return (~cpsr) & PSR_Z_BIT;
+
+	case 0x2: /* cs */
+		return cpsr & PSR_C_BIT;
+
+	case 0x3: /* cc */
+		return (~cpsr) & PSR_C_BIT;
+
+	case 0x4: /* mi */
+		return cpsr & PSR_N_BIT;
+
+	case 0x5: /* pl */
+		return (~cpsr) & PSR_N_BIT;
+
+	case 0x6: /* vs */
+		return cpsr & PSR_V_BIT;
+
+	case 0x7: /* vc */
+		return (~cpsr) & PSR_V_BIT;
+
+	case 0x8: /* hi */
+		cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+		return cpsr & PSR_C_BIT;
+
+	case 0x9: /* ls */
+		cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+		return (~cpsr) & PSR_C_BIT;
+
+	case 0xa: /* ge */
+		cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+		return (~cpsr) & PSR_N_BIT;
+
+	case 0xb: /* lt */
+		cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+		return cpsr & PSR_N_BIT;
+
+	case 0xc: /* gt */
+		temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+		temp |= (cpsr << 1);	   /* PSR_N_BIT |= PSR_Z_BIT */
+		return (~temp) & PSR_N_BIT;
+
+	case 0xd: /* le */
+		temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+		temp |= (cpsr << 1);	   /* PSR_N_BIT |= PSR_Z_BIT */
+		return temp & PSR_N_BIT;
+
+	case 0xe: /* al */
+	case 0xf: /* unconditional */
+		return true;
+	}
+	BUG();
+	return false;
+}
+
+static int is_last_scenario;
+static int probe_should_run; /* 0 = no, 1 = yes, -1 = unknown */
+static int memory_needs_checking;
+
+static unsigned long test_context_cpsr(int scenario)
+{
+	unsigned long cpsr;
+
+	probe_should_run = 1;
+
+	/* Default case is that we cycle through 16 combinations of flags */
+	cpsr  = (scenario & 0xf) << 28; /* N,Z,C,V flags */
+	cpsr |= (scenario & 0xf) << 16; /* GE flags */
+	cpsr |= (scenario & 0x1) << 27; /* Toggle Q flag */
+
+	if (!test_case_is_thumb) {
+		/* Testing ARM code */
+		probe_should_run = test_check_cc(current_instruction >> 28, cpsr) != 0;
+		if (scenario == 15)
+			is_last_scenario = true;
+
+	} else if (kprobe_test_flags & TEST_FLAG_NO_ITBLOCK) {
+		/* Testing Thumb code without setting ITSTATE */
+		if (kprobe_test_cc_position) {
+			int cc = (current_instruction >> kprobe_test_cc_position) & 0xf;
+			probe_should_run = test_check_cc(cc, cpsr) != 0;
+		}
+
+		if (scenario == 15)
+			is_last_scenario = true;
+
+	} else if (kprobe_test_flags & TEST_FLAG_FULL_ITBLOCK) {
+		/* Testing Thumb code with all combinations of ITSTATE */
+		unsigned x = (scenario >> 4);
+		unsigned cond_base = x % 7; /* ITSTATE<7:5> */
+		unsigned mask = x / 7 + 2;  /* ITSTATE<4:0>, bits reversed */
+
+		if (mask > 0x1f) {
+			/* Finish by testing state from instruction 'itt al' */
+			cond_base = 7;
+			mask = 0x4;
+			if ((scenario & 0xf) == 0xf)
+				is_last_scenario = true;
+		}
+
+		cpsr |= cond_base << 13;	/* ITSTATE<7:5> */
+		cpsr |= (mask & 0x1) << 12;	/* ITSTATE<4> */
+		cpsr |= (mask & 0x2) << 10;	/* ITSTATE<3> */
+		cpsr |= (mask & 0x4) << 8;	/* ITSTATE<2> */
+		cpsr |= (mask & 0x8) << 23;	/* ITSTATE<1> */
+		cpsr |= (mask & 0x10) << 21;	/* ITSTATE<0> */
+
+		probe_should_run = test_check_cc((cpsr >> 12) & 0xf, cpsr) != 0;
+
+	} else {
+		/* Testing Thumb code with several combinations of ITSTATE */
+		switch (scenario) {
+		case 16: /* Clear NZCV flags and 'it eq' state (false as Z=0) */
+			cpsr = 0x00000800;
+			probe_should_run = 0;
+			break;
+		case 17: /* Set NZCV flags and 'it vc' state (false as V=1) */
+			cpsr = 0xf0007800;
+			probe_should_run = 0;
+			break;
+		case 18: /* Clear NZCV flags and 'it ls' state (true as C=0) */
+			cpsr = 0x00009800;
+			break;
+		case 19: /* Set NZCV flags and 'it cs' state (true as C=1) */
+			cpsr = 0xf0002800;
+			is_last_scenario = true;
+			break;
+		}
+	}
+
+	return cpsr;
+}
+
+static void setup_test_context(struct pt_regs *regs)
+{
+	int scenario = test_case_run_count>>1;
+	unsigned long val;
+	struct test_arg *args;
+	int i;
+
+	is_last_scenario = false;
+	memory_needs_checking = false;
+
+	/* Initialise test memory on stack */
+	val = (scenario & 1) ? VALM : ~VALM;
+	for (i = 0; i < TEST_MEMORY_SIZE / sizeof(current_stack[0]); ++i)
+		current_stack[i] = val + (i << 8);
+	/* Put target of branch on stack for tests which load PC from memory */
+	if (current_branch_target)
+		current_stack[15] = current_branch_target;
+	/* Put a value for SP on stack for tests which load SP from memory */
+	current_stack[13] = (u32)current_stack + 120;
+
+	/* Initialise register values to their default state */
+	val = (scenario & 2) ? VALR : ~VALR;
+	for (i = 0; i < 13; ++i)
+		regs->uregs[i] = val ^ (i << 8);
+	regs->ARM_lr = val ^ (14 << 8);
+	regs->ARM_cpsr &= ~(APSR_MASK | PSR_IT_MASK);
+	regs->ARM_cpsr |= test_context_cpsr(scenario);
+
+	/* Perform testcase specific register setup  */
+	args = current_args;
+	for (; args[0].type != ARG_TYPE_END; ++args)
+		switch (args[0].type) {
+		case ARG_TYPE_REG: {
+			struct test_arg_regptr *arg =
+				(struct test_arg_regptr *)args;
+			regs->uregs[arg->reg] = arg->val;
+			break;
+		}
+		case ARG_TYPE_PTR: {
+			struct test_arg_regptr *arg =
+				(struct test_arg_regptr *)args;
+			regs->uregs[arg->reg] =
+				(unsigned long)current_stack + arg->val;
+			memory_needs_checking = true;
+			break;
+		}
+		case ARG_TYPE_MEM: {
+			struct test_arg_mem *arg = (struct test_arg_mem *)args;
+			current_stack[arg->index] = arg->val;
+			break;
+		}
+		default:
+			break;
+		}
+}
+
+struct test_probe {
+	struct kprobe	kprobe;
+	bool		registered;
+	int		hit;
+};
+
+static void unregister_test_probe(struct test_probe *probe)
+{
+	if (probe->registered) {
+		unregister_kprobe(&probe->kprobe);
+		probe->kprobe.flags = 0; /* Clear disable flag to allow reuse */
+	}
+	probe->registered = false;
+}
+
+static int register_test_probe(struct test_probe *probe)
+{
+	int ret;
+
+	if (probe->registered)
+		BUG();
+
+	ret = register_kprobe(&probe->kprobe);
+	if (ret >= 0) {
+		probe->registered = true;
+		probe->hit = -1;
+	}
+	return ret;
+}
+
+static int __kprobes
+test_before_pre_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	container_of(p, struct test_probe, kprobe)->hit = test_instance;
+	return 0;
+}
+
+static void __kprobes
+test_before_post_handler(struct kprobe *p, struct pt_regs *regs,
+							unsigned long flags)
+{
+	setup_test_context(regs);
+	initial_regs = *regs;
+	initial_regs.ARM_cpsr &= ~PSR_IGNORE_BITS;
+}
+
+static int __kprobes
+test_case_pre_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	container_of(p, struct test_probe, kprobe)->hit = test_instance;
+	return 0;
+}
+
+static int __kprobes
+test_after_pre_handler(struct kprobe *p, struct pt_regs *regs)
+{
+	if (container_of(p, struct test_probe, kprobe)->hit == test_instance)
+		return 0; /* Already run for this test instance */
+
+	result_regs = *regs;
+	result_regs.ARM_cpsr &= ~PSR_IGNORE_BITS;
+
+	/* Undo any changes done to SP by the test case */
+	regs->ARM_sp = (unsigned long)current_stack;
+
+	container_of(p, struct test_probe, kprobe)->hit = test_instance;
+	return 0;
+}
+
+static struct test_probe test_before_probe = {
+	.kprobe.pre_handler	= test_before_pre_handler,
+	.kprobe.post_handler	= test_before_post_handler,
+};
+
+static struct test_probe test_case_probe = {
+	.kprobe.pre_handler	= test_case_pre_handler,
+};
+
+static struct test_probe test_after_probe = {
+	.kprobe.pre_handler	= test_after_pre_handler,
+};
+
+static struct test_probe test_after2_probe = {
+	.kprobe.pre_handler	= test_after_pre_handler,
+};
+
+static void test_case_cleanup(void)
+{
+	unregister_test_probe(&test_before_probe);
+	unregister_test_probe(&test_case_probe);
+	unregister_test_probe(&test_after_probe);
+	unregister_test_probe(&test_after2_probe);
+}
+
+static void print_registers(struct pt_regs *regs)
+{
+	pr_err("r0  %08lx | r1  %08lx | r2  %08lx | r3  %08lx\n",
+		regs->ARM_r0, regs->ARM_r1, regs->ARM_r2, regs->ARM_r3);
+	pr_err("r4  %08lx | r5  %08lx | r6  %08lx | r7  %08lx\n",
+		regs->ARM_r4, regs->ARM_r5, regs->ARM_r6, regs->ARM_r7);
+	pr_err("r8  %08lx | r9  %08lx | r10 %08lx | r11 %08lx\n",
+		regs->ARM_r8, regs->ARM_r9, regs->ARM_r10, regs->ARM_fp);
+	pr_err("r12 %08lx | sp  %08lx | lr  %08lx | pc  %08lx\n",
+		regs->ARM_ip, regs->ARM_sp, regs->ARM_lr, regs->ARM_pc);
+	pr_err("cpsr %08lx\n", regs->ARM_cpsr);
+}
+
+static void print_memory(u32 *mem, size_t size)
+{
+	int i;
+	for (i = 0; i < size / sizeof(u32); i += 4)
+		pr_err("%08x %08x %08x %08x\n", mem[i], mem[i+1],
+						mem[i+2], mem[i+3]);
+}
+
+static size_t expected_memory_size(u32 *sp)
+{
+	size_t size = sizeof(expected_memory);
+	int offset = (uintptr_t)sp - (uintptr_t)current_stack;
+	if (offset > 0)
+		size -= offset;
+	return size;
+}
+
+static void test_case_failed(const char *message)
+{
+	test_case_cleanup();
+
+	pr_err("FAIL: %s\n", message);
+	pr_err("FAIL: Test %s\n", current_title);
+	pr_err("FAIL: Scenario %d\n", test_case_run_count >> 1);
+}
+
+static unsigned long next_instruction(unsigned long pc)
+{
+#ifdef CONFIG_THUMB2_KERNEL
+	if ((pc & 1) && !is_wide_instruction(*(u16 *)(pc - 1)))
+		return pc + 2;
+	else
+#endif
+	return pc + 4;
+}
+
+static uintptr_t __used kprobes_test_case_start(const char *title, void *stack)
+{
+	struct test_arg *args;
+	struct test_arg_end *end_arg;
+	unsigned long test_code;
+
+	args = (struct test_arg *)PTR_ALIGN(title + strlen(title) + 1, 4);
+
+	current_title = title;
+	current_args = args;
+	current_stack = stack;
+
+	++test_try_count;
+
+	while (args->type != ARG_TYPE_END)
+		++args;
+	end_arg = (struct test_arg_end *)args;
+
+	test_code = (unsigned long)(args + 1); /* Code starts after args */
+
+	test_case_is_thumb = end_arg->flags & ARG_FLAG_THUMB;
+	if (test_case_is_thumb)
+		test_code |= 1;
+
+	current_code_start = test_code;
+
+	current_branch_target = 0;
+	if (end_arg->branch_offset != end_arg->end_offset)
+		current_branch_target = test_code + end_arg->branch_offset;
+
+	test_code += end_arg->code_offset;
+	test_before_probe.kprobe.addr = (kprobe_opcode_t *)test_code;
+
+	test_code = next_instruction(test_code);
+	test_case_probe.kprobe.addr = (kprobe_opcode_t *)test_code;
+
+	if (test_case_is_thumb) {
+		u16 *p = (u16 *)(test_code & ~1);
+		current_instruction = p[0];
+		if (is_wide_instruction(current_instruction)) {
+			current_instruction <<= 16;
+			current_instruction |= p[1];
+		}
+	} else {
+		current_instruction = *(u32 *)test_code;
+	}
+
+	if (current_title[0] == '.')
+		verbose("%s\n", current_title);
+	else
+		verbose("%s\t@ %0*x\n", current_title,
+					test_case_is_thumb ? 4 : 8,
+					current_instruction);
+
+	test_code = next_instruction(test_code);
+	test_after_probe.kprobe.addr = (kprobe_opcode_t *)test_code;
+
+	if (kprobe_test_flags & TEST_FLAG_NARROW_INSTR) {
+		if (!test_case_is_thumb ||
+			is_wide_instruction(current_instruction)) {
+				test_case_failed("expected 16-bit instruction");
+				goto fail;
+		}
+	} else {
+		if (test_case_is_thumb &&
+			!is_wide_instruction(current_instruction)) {
+				test_case_failed("expected 32-bit instruction");
+				goto fail;
+		}
+	}
+
+	coverage_add(current_instruction);
+
+	if (end_arg->flags & ARG_FLAG_UNSUPPORTED) {
+		if (register_test_probe(&test_case_probe) < 0)
+			goto pass;
+		test_case_failed("registered probe for unsupported instruction");
+		goto fail;
+	}
+
+	if (end_arg->flags & ARG_FLAG_SUPPORTED) {
+		if (register_test_probe(&test_case_probe) >= 0)
+			goto pass;
+		test_case_failed("couldn't register probe for supported instruction");
+		goto fail;
+	}
+
+	if (register_test_probe(&test_before_probe) < 0) {
+		test_case_failed("register test_before_probe failed");
+		goto fail;
+	}
+	if (register_test_probe(&test_after_probe) < 0) {
+		test_case_failed("register test_after_probe failed");
+		goto fail;
+	}
+	if (current_branch_target) {
+		test_after2_probe.kprobe.addr =
+				(kprobe_opcode_t *)current_branch_target;
+		if (register_test_probe(&test_after2_probe) < 0) {
+			test_case_failed("register test_after2_probe failed");
+			goto fail;
+		}
+	}
+
+	/* Start first run of test case */
+	test_case_run_count = 0;
+	++test_instance;
+	return current_code_start;
+pass:
+	test_case_run_count = TEST_CASE_PASSED;
+	return (uintptr_t)test_after_probe.kprobe.addr;
+fail:
+	test_case_run_count = TEST_CASE_FAILED;
+	return (uintptr_t)test_after_probe.kprobe.addr;
+}
+
+static bool check_test_results(void)
+{
+	size_t mem_size = 0;
+	u32 *mem = 0;
+
+	if (memcmp(&expected_regs, &result_regs, sizeof(expected_regs))) {
+		test_case_failed("registers differ");
+		goto fail;
+	}
+
+	if (memory_needs_checking) {
+		mem = (u32 *)result_regs.ARM_sp;
+		mem_size = expected_memory_size(mem);
+		if (memcmp(expected_memory, mem, mem_size)) {
+			test_case_failed("test memory differs");
+			goto fail;
+		}
+	}
+
+	return true;
+
+fail:
+	pr_err("initial_regs:\n");
+	print_registers(&initial_regs);
+	pr_err("expected_regs:\n");
+	print_registers(&expected_regs);
+	pr_err("result_regs:\n");
+	print_registers(&result_regs);
+
+	if (mem) {
+		pr_err("current_stack=%p\n", current_stack);
+		pr_err("expected_memory:\n");
+		print_memory(expected_memory, mem_size);
+		pr_err("result_memory:\n");
+		print_memory(mem, mem_size);
+	}
+
+	return false;
+}
+
+static uintptr_t __used kprobes_test_case_end(void)
+{
+	if (test_case_run_count < 0) {
+		if (test_case_run_count == TEST_CASE_PASSED)
+			/* kprobes_test_case_start did all the needed testing */
+			goto pass;
+		else
+			/* kprobes_test_case_start failed */
+			goto fail;
+	}
+
+	if (test_before_probe.hit != test_instance) {
+		test_case_failed("test_before_handler not run");
+		goto fail;
+	}
+
+	if (test_after_probe.hit != test_instance &&
+				test_after2_probe.hit != test_instance) {
+		test_case_failed("test_after_handler not run");
+		goto fail;
+	}
+
+	/*
+	 * Even numbered test runs ran without a probe on the test case so
+	 * we can gather reference results. The subsequent odd numbered run
+	 * will have the probe inserted.
+	*/
+	if ((test_case_run_count & 1) == 0) {
+		/* Save results from run without probe */
+		u32 *mem = (u32 *)result_regs.ARM_sp;
+		expected_regs = result_regs;
+		memcpy(expected_memory, mem, expected_memory_size(mem));
+
+		/* Insert probe onto test case instruction */
+		if (register_test_probe(&test_case_probe) < 0) {
+			test_case_failed("register test_case_probe failed");
+			goto fail;
+		}
+	} else {
+		/* Check probe ran as expected */
+		if (probe_should_run == 1) {
+			if (test_case_probe.hit != test_instance) {
+				test_case_failed("test_case_handler not run");
+				goto fail;
+			}
+		} else if (probe_should_run == 0) {
+			if (test_case_probe.hit == test_instance) {
+				test_case_failed("test_case_handler ran");
+				goto fail;
+			}
+		}
+
+		/* Remove probe for any subsequent reference run */
+		unregister_test_probe(&test_case_probe);
+
+		if (!check_test_results())
+			goto fail;
+
+		if (is_last_scenario)
+			goto pass;
+	}
+
+	/* Do next test run */
+	++test_case_run_count;
+	++test_instance;
+	return current_code_start;
+fail:
+	++test_fail_count;
+	goto end;
+pass:
+	++test_pass_count;
+end:
+	test_case_cleanup();
+	return 0;
+}
+
+
+/*
+ * Top level test functions
+ */
+
+static int run_test_cases(void (*tests)(void), const union decode_item *table)
+{
+	int ret;
+
+	pr_info("    Check decoding tables\n");
+	ret = table_test(table);
+	if (ret)
+		return ret;
+
+	pr_info("    Run test cases\n");
+	ret = coverage_start(table);
+	if (ret)
+		return ret;
+
+	tests();
+
+	coverage_end();
+	return 0;
+}
+
+
+static int __init run_all_tests(void)
+{
+	int ret = 0;
+
+	pr_info("Begining kprobe tests...\n");
+
+#ifndef CONFIG_THUMB2_KERNEL
+
+	pr_info("Probe ARM code\n");
+	ret = run_api_tests(arm_func);
+	if (ret)
+		goto out;
+
+	pr_info("ARM instruction simulation\n");
+	ret = run_test_cases(kprobe_arm_test_cases, kprobe_decode_arm_table);
+	if (ret)
+		goto out;
+
+#else /* CONFIG_THUMB2_KERNEL */
+
+	pr_info("Probe 16-bit Thumb code\n");
+	ret = run_api_tests(thumb16_func);
+	if (ret)
+		goto out;
+
+	pr_info("Probe 32-bit Thumb code, even halfword\n");
+	ret = run_api_tests(thumb32even_func);
+	if (ret)
+		goto out;
+
+	pr_info("Probe 32-bit Thumb code, odd halfword\n");
+	ret = run_api_tests(thumb32odd_func);
+	if (ret)
+		goto out;
+
+	pr_info("16-bit Thumb instruction simulation\n");
+	ret = run_test_cases(kprobe_thumb16_test_cases,
+				kprobe_decode_thumb16_table);
+	if (ret)
+		goto out;
+
+	pr_info("32-bit Thumb instruction simulation\n");
+	ret = run_test_cases(kprobe_thumb32_test_cases,
+				kprobe_decode_thumb32_table);
+	if (ret)
+		goto out;
+#endif
+
+	pr_info("Total instruction simulation tests=%d, pass=%d fail=%d\n",
+		test_try_count, test_pass_count, test_fail_count);
+	if (test_fail_count) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+#if BENCHMARKING
+	pr_info("Benchmarks\n");
+	ret = run_benchmarks();
+	if (ret)
+		goto out;
+#endif
+
+#if __LINUX_ARM_ARCH__ >= 7
+	/* We are able to run all test cases so coverage should be complete */
+	if (coverage_fail) {
+		pr_err("FAIL: Test coverage checks failed\n");
+		ret = -EINVAL;
+		goto out;
+	}
+#endif
+
+out:
+	if (ret == 0)
+		pr_info("Finished kprobe tests OK\n");
+	else
+		pr_err("kprobe tests failed\n");
+
+	return ret;
+}
+
+
+/*
+ * Module setup
+ */
+
+#ifdef MODULE
+
+static void __exit kprobe_test_exit(void)
+{
+}
+
+module_init(run_all_tests)
+module_exit(kprobe_test_exit)
+MODULE_LICENSE("GPL");
+
+#else /* !MODULE */
+
+late_initcall(run_all_tests);
+
+#endif