diff options
Diffstat (limited to 'arch/arm/kernel/kprobes-test.c')
| -rw-r--r-- | arch/arm/kernel/kprobes-test.c | 840 |
1 files changed, 840 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-test.c b/arch/arm/kernel/kprobes-test.c index 9fff0448c32..e22c3f2aff1 100644 --- a/arch/arm/kernel/kprobes-test.c +++ b/arch/arm/kernel/kprobes-test.c @@ -8,11 +8,180 @@ * published by the Free Software Foundation. */ +/* + * 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/kprobes.h> #include "kprobes.h" +#include "kprobes-test.h" /* @@ -274,6 +443,677 @@ static int run_api_tests(long (*func)(long, long)) /* + * 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; + } + } + + 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 */ |