summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/kprobes-test.h
diff options
context:
space:
mode:
authorJon Medhurst <tixy@yxit.co.uk>2011-08-28 16:18:43 +0100
committerJon Medhurst <tixy@yxit.co.uk>2011-09-20 18:17:43 +0000
commita43bc69b39484a448293f2eddc7e98ff15437414 (patch)
tree5c40ccc0517618971a1e9660b6816dbf2b6b096a /arch/arm/kernel/kprobes-test.h
parent9eed1797720ae633cf17b03dd804d8744f1d3b5c (diff)
ARM: kprobes: Framework for instruction set test cases
On ARM we have to simulate/emulate CPU instructions in order to singlestep them. This patch adds a framework which can be used to construct test cases for different instruction forms. It is described in detail in the in-source comments of kprobes-test.c Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Diffstat (limited to 'arch/arm/kernel/kprobes-test.h')
-rw-r--r--arch/arm/kernel/kprobes-test.h384
1 files changed, 384 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-test.h b/arch/arm/kernel/kprobes-test.h
new file mode 100644
index 00000000000..50ecc2a3643
--- /dev/null
+++ b/arch/arm/kernel/kprobes-test.h
@@ -0,0 +1,384 @@
+/*
+ * arch/arm/kernel/kprobes-test.h
+ *
+ * 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.
+ */
+
+#define VERBOSE 0 /* Set to '1' for more logging of test cases */
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define NORMAL_ISA "16"
+#else
+#define NORMAL_ISA "32"
+#endif
+
+
+/* Flags used in kprobe_test_flags */
+#define TEST_FLAG_NO_ITBLOCK (1<<0)
+#define TEST_FLAG_FULL_ITBLOCK (1<<1)
+#define TEST_FLAG_NARROW_INSTR (1<<2)
+
+extern int kprobe_test_flags;
+extern int kprobe_test_cc_position;
+
+
+#define TEST_MEMORY_SIZE 256
+
+
+/*
+ * Test case structures.
+ *
+ * The arguments given to test cases can be one of three types.
+ *
+ * ARG_TYPE_REG
+ * Load a register with the given value.
+ *
+ * ARG_TYPE_PTR
+ * Load a register with a pointer into the stack buffer (SP + given value).
+ *
+ * ARG_TYPE_MEM
+ * Store the given value into the stack buffer at [SP+index].
+ *
+ */
+
+#define ARG_TYPE_END 0
+#define ARG_TYPE_REG 1
+#define ARG_TYPE_PTR 2
+#define ARG_TYPE_MEM 3
+
+#define ARG_FLAG_UNSUPPORTED 0x01
+#define ARG_FLAG_SUPPORTED 0x02
+#define ARG_FLAG_THUMB 0x10 /* Must be 16 so TEST_ISA can be used */
+#define ARG_FLAG_ARM 0x20 /* Must be 32 so TEST_ISA can be used */
+
+struct test_arg {
+ u8 type; /* ARG_TYPE_x */
+ u8 _padding[7];
+};
+
+struct test_arg_regptr {
+ u8 type; /* ARG_TYPE_REG or ARG_TYPE_PTR */
+ u8 reg;
+ u8 _padding[2];
+ u32 val;
+};
+
+struct test_arg_mem {
+ u8 type; /* ARG_TYPE_MEM */
+ u8 index;
+ u8 _padding[2];
+ u32 val;
+};
+
+struct test_arg_end {
+ u8 type; /* ARG_TYPE_END */
+ u8 flags; /* ARG_FLAG_x */
+ u16 code_offset;
+ u16 branch_offset;
+ u16 end_offset;
+};
+
+
+/*
+ * Building blocks for test cases.
+ *
+ * Each test case is wrapped between TESTCASE_START and TESTCASE_END.
+ *
+ * To specify arguments for a test case the TEST_ARG_{REG,PTR,MEM} macros are
+ * used followed by a terminating TEST_ARG_END.
+ *
+ * After this, the instruction to be tested is defined with TEST_INSTRUCTION.
+ * Or for branches, TEST_BRANCH_B and TEST_BRANCH_F (branch forwards/backwards).
+ *
+ * Some specific test cases may make use of other custom constructs.
+ */
+
+#if VERBOSE
+#define verbose(fmt, ...) pr_info(fmt, ##__VA_ARGS__)
+#else
+#define verbose(fmt, ...)
+#endif
+
+#define TEST_GROUP(title) \
+ verbose("\n"); \
+ verbose(title"\n"); \
+ verbose("---------------------------------------------------------\n");
+
+#define TESTCASE_START(title) \
+ __asm__ __volatile__ ( \
+ "bl __kprobes_test_case_start \n\t" \
+ /* don't use .asciz here as 'title' may be */ \
+ /* multiple strings to be concatenated. */ \
+ ".ascii "#title" \n\t" \
+ ".byte 0 \n\t" \
+ ".align 2 \n\t"
+
+#define TEST_ARG_REG(reg, val) \
+ ".byte "__stringify(ARG_TYPE_REG)" \n\t" \
+ ".byte "#reg" \n\t" \
+ ".short 0 \n\t" \
+ ".word "#val" \n\t"
+
+#define TEST_ARG_PTR(reg, val) \
+ ".byte "__stringify(ARG_TYPE_PTR)" \n\t" \
+ ".byte "#reg" \n\t" \
+ ".short 0 \n\t" \
+ ".word "#val" \n\t"
+
+#define TEST_ARG_MEM(index, val) \
+ ".byte "__stringify(ARG_TYPE_MEM)" \n\t" \
+ ".byte "#index" \n\t" \
+ ".short 0 \n\t" \
+ ".word "#val" \n\t"
+
+#define TEST_ARG_END(flags) \
+ ".byte "__stringify(ARG_TYPE_END)" \n\t" \
+ ".byte "TEST_ISA flags" \n\t" \
+ ".short 50f-0f \n\t" \
+ ".short 2f-0f \n\t" \
+ ".short 99f-0f \n\t" \
+ ".code "TEST_ISA" \n\t" \
+ "0: \n\t"
+
+#define TEST_INSTRUCTION(instruction) \
+ "50: nop \n\t" \
+ "1: "instruction" \n\t" \
+ " nop \n\t"
+
+#define TEST_BRANCH_F(instruction, xtra_dist) \
+ TEST_INSTRUCTION(instruction) \
+ ".if "#xtra_dist" \n\t" \
+ " b 99f \n\t" \
+ ".space "#xtra_dist" \n\t" \
+ ".endif \n\t" \
+ " b 99f \n\t" \
+ "2: nop \n\t"
+
+#define TEST_BRANCH_B(instruction, xtra_dist) \
+ " b 50f \n\t" \
+ " b 99f \n\t" \
+ "2: nop \n\t" \
+ " b 99f \n\t" \
+ ".if "#xtra_dist" \n\t" \
+ ".space "#xtra_dist" \n\t" \
+ ".endif \n\t" \
+ TEST_INSTRUCTION(instruction)
+
+#define TESTCASE_END \
+ "2: \n\t" \
+ "99: \n\t" \
+ " bl __kprobes_test_case_end_"TEST_ISA" \n\t" \
+ ".code "NORMAL_ISA" \n\t" \
+ : : \
+ : "r0", "r1", "r2", "r3", "ip", "lr", "memory", "cc" \
+ );
+
+
+/*
+ * Macros to define test cases.
+ *
+ * Those of the form TEST_{R,P,M}* can be used to define test cases
+ * which take combinations of the three basic types of arguments. E.g.
+ *
+ * TEST_R One register argument
+ * TEST_RR Two register arguments
+ * TEST_RPR A register, a pointer, then a register argument
+ *
+ * For testing instructions which may branch, there are macros TEST_BF_*
+ * and TEST_BB_* for branching forwards and backwards.
+ *
+ * TEST_SUPPORTED and TEST_UNSUPPORTED don't cause the code to be executed,
+ * the just verify that a kprobe is or is not allowed on the given instruction.
+ */
+
+#define TEST(code) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code) \
+ TESTCASE_END
+
+#define TEST_UNSUPPORTED(code) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("|"__stringify(ARG_FLAG_UNSUPPORTED)) \
+ TEST_INSTRUCTION(code) \
+ TESTCASE_END
+
+#define TEST_SUPPORTED(code) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("|"__stringify(ARG_FLAG_SUPPORTED)) \
+ TEST_INSTRUCTION(code) \
+ TESTCASE_END
+
+#define TEST_R(code1, reg, val, code2) \
+ TESTCASE_START(code1 #reg code2) \
+ TEST_ARG_REG(reg, val) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg code2) \
+ TESTCASE_END
+
+#define TEST_RR(code1, reg1, val1, code2, reg2, val2, code3) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3) \
+ TESTCASE_END
+
+#define TEST_RRR(code1, reg1, val1, code2, reg2, val2, code3, reg3, val3, code4)\
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_REG(reg3, val3) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TESTCASE_END
+
+#define TEST_RRRR(code1, reg1, val1, code2, reg2, val2, code3, reg3, val3, code4, reg4, val4) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3 #reg3 code4 #reg4) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_REG(reg3, val3) \
+ TEST_ARG_REG(reg4, val4) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3 #reg3 code4 #reg4) \
+ TESTCASE_END
+
+#define TEST_P(code1, reg1, val1, code2) \
+ TESTCASE_START(code1 #reg1 code2) \
+ TEST_ARG_PTR(reg1, val1) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2) \
+ TESTCASE_END
+
+#define TEST_PR(code1, reg1, val1, code2, reg2, val2, code3) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3) \
+ TEST_ARG_PTR(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3) \
+ TESTCASE_END
+
+#define TEST_RP(code1, reg1, val1, code2, reg2, val2, code3) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_PTR(reg2, val2) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3) \
+ TESTCASE_END
+
+#define TEST_PRR(code1, reg1, val1, code2, reg2, val2, code3, reg3, val3, code4)\
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TEST_ARG_PTR(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_REG(reg3, val3) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TESTCASE_END
+
+#define TEST_RPR(code1, reg1, val1, code2, reg2, val2, code3, reg3, val3, code4)\
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_PTR(reg2, val2) \
+ TEST_ARG_REG(reg3, val3) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TESTCASE_END
+
+#define TEST_RRP(code1, reg1, val1, code2, reg2, val2, code3, reg3, val3, code4)\
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_PTR(reg3, val3) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 #reg1 code2 #reg2 code3 #reg3 code4) \
+ TESTCASE_END
+
+#define TEST_BF_P(code1, reg1, val1, code2) \
+ TESTCASE_START(code1 #reg1 code2) \
+ TEST_ARG_PTR(reg1, val1) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_F(code1 #reg1 code2, 0) \
+ TESTCASE_END
+
+#define TEST_BF_X(code, xtra_dist) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_F(code, xtra_dist) \
+ TESTCASE_END
+
+#define TEST_BB_X(code, xtra_dist) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_B(code, xtra_dist) \
+ TESTCASE_END
+
+#define TEST_BF_RX(code1, reg, val, code2, xtra_dist) \
+ TESTCASE_START(code1 #reg code2) \
+ TEST_ARG_REG(reg, val) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_F(code1 #reg code2, xtra_dist) \
+ TESTCASE_END
+
+#define TEST_BB_RX(code1, reg, val, code2, xtra_dist) \
+ TESTCASE_START(code1 #reg code2) \
+ TEST_ARG_REG(reg, val) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_B(code1 #reg code2, xtra_dist) \
+ TESTCASE_END
+
+#define TEST_BF(code) TEST_BF_X(code, 0)
+#define TEST_BB(code) TEST_BB_X(code, 0)
+
+#define TEST_BF_R(code1, reg, val, code2) TEST_BF_RX(code1, reg, val, code2, 0)
+#define TEST_BB_R(code1, reg, val, code2) TEST_BB_RX(code1, reg, val, code2, 0)
+
+#define TEST_BF_RR(code1, reg1, val1, code2, reg2, val2, code3) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_END("") \
+ TEST_BRANCH_F(code1 #reg1 code2 #reg2 code3, 0) \
+ TESTCASE_END
+
+#define TEST_X(code, codex) \
+ TESTCASE_START(code) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code) \
+ " b 99f \n\t" \
+ " "codex" \n\t" \
+ TESTCASE_END
+
+#define TEST_RX(code1, reg, val, code2, codex) \
+ TESTCASE_START(code1 #reg code2) \
+ TEST_ARG_REG(reg, val) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 __stringify(reg) code2) \
+ " b 99f \n\t" \
+ " "codex" \n\t" \
+ TESTCASE_END
+
+#define TEST_RRX(code1, reg1, val1, code2, reg2, val2, code3, codex) \
+ TESTCASE_START(code1 #reg1 code2 #reg2 code3) \
+ TEST_ARG_REG(reg1, val1) \
+ TEST_ARG_REG(reg2, val2) \
+ TEST_ARG_END("") \
+ TEST_INSTRUCTION(code1 __stringify(reg1) code2 __stringify(reg2) code3) \
+ " b 99f \n\t" \
+ " "codex" \n\t" \
+ TESTCASE_END
+
+
+/* Various values used in test cases... */
+#define N(val) (val ^ 0xffffffff)
+#define VAL1 0x12345678
+#define VAL2 N(VAL1)
+#define VAL3 0xa5f801
+#define VAL4 N(VAL3)
+#define VALM 0x456789ab
+#define VALR 0xdeaddead
+#define HH1 0x0123fecb
+#define HH2 0xa9874567