1 /* 2 * Test for x86 debugging facilities 3 * 4 * Copyright (c) Siemens AG, 2014 5 * 6 * Authors: 7 * Jan Kiszka <jan.kiszka@siemens.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. 10 */ 11 12 #include "libcflat.h" 13 #include "desc.h" 14 15 static volatile unsigned long bp_addr[10], dr6[10]; 16 static volatile unsigned int n; 17 static volatile unsigned long value; 18 19 static unsigned long get_dr6(void) 20 { 21 unsigned long value; 22 23 asm volatile("mov %%dr6,%0" : "=r" (value)); 24 return value; 25 } 26 27 static void set_dr0(void *value) 28 { 29 asm volatile("mov %0,%%dr0" : : "r" (value)); 30 } 31 32 static void set_dr1(void *value) 33 { 34 asm volatile("mov %0,%%dr1" : : "r" (value)); 35 } 36 37 static void set_dr6(unsigned long value) 38 { 39 asm volatile("mov %0,%%dr6" : : "r" (value)); 40 } 41 42 static void set_dr7(unsigned long value) 43 { 44 asm volatile("mov %0,%%dr7" : : "r" (value)); 45 } 46 47 static void handle_db(struct ex_regs *regs) 48 { 49 bp_addr[n] = regs->rip; 50 dr6[n] = get_dr6(); 51 52 if (dr6[n] & 0x1) 53 regs->rflags |= (1 << 16); 54 55 if (++n >= 10) { 56 regs->rflags &= ~(1 << 8); 57 set_dr7(0x00000400); 58 } 59 } 60 61 static void handle_bp(struct ex_regs *regs) 62 { 63 bp_addr[0] = regs->rip; 64 } 65 66 int main(int ac, char **av) 67 { 68 unsigned long start; 69 70 setup_idt(); 71 handle_exception(DB_VECTOR, handle_db); 72 handle_exception(BP_VECTOR, handle_bp); 73 74 sw_bp: 75 asm volatile("int3"); 76 report("#BP", bp_addr[0] == (unsigned long)&&sw_bp + 1); 77 78 n = 0; 79 set_dr0(&&hw_bp1); 80 set_dr7(0x00000402); 81 hw_bp1: 82 asm volatile("nop"); 83 report("hw breakpoint (test that dr6.BS is not set)", 84 n == 1 && 85 bp_addr[0] == ((unsigned long)&&hw_bp1) && dr6[0] == 0xffff0ff1); 86 87 n = 0; 88 set_dr0(&&hw_bp2); 89 set_dr6(0x00004002); 90 hw_bp2: 91 asm volatile("nop"); 92 report("hw breakpoint (test that dr6.BS is not cleared)", 93 n == 1 && 94 bp_addr[0] == ((unsigned long)&&hw_bp2) && dr6[0] == 0xffff4ff1); 95 96 n = 0; 97 set_dr6(0); 98 asm volatile( 99 "pushf\n\t" 100 "pop %%rax\n\t" 101 "or $(1<<8),%%rax\n\t" 102 "push %%rax\n\t" 103 "lea (%%rip),%0\n\t" 104 "popf\n\t" 105 "and $~(1<<8),%%rax\n\t" 106 "push %%rax\n\t" 107 "popf\n\t" 108 : "=g" (start) : : "rax"); 109 report("single step", 110 n == 3 && 111 bp_addr[0] == start+1+6 && dr6[0] == 0xffff4ff0 && 112 bp_addr[1] == start+1+6+1 && dr6[1] == 0xffff4ff0 && 113 bp_addr[2] == start+1+6+1+1 && dr6[2] == 0xffff4ff0); 114 115 n = 0; 116 set_dr1((void *)&value); 117 set_dr7(0x00d0040a); 118 119 asm volatile( 120 "mov $42,%%rax\n\t" 121 "mov %%rax,%0\n\t" 122 : "=m" (value) : : "rax"); 123 hw_wp1: 124 report("hw watchpoint (test that dr6.BS is not cleared)", 125 n == 1 && 126 bp_addr[0] == ((unsigned long)&&hw_wp1) && dr6[0] == 0xffff4ff2); 127 128 n = 0; 129 set_dr6(0); 130 131 asm volatile( 132 "mov $42,%%rax\n\t" 133 "mov %%rax,%0\n\t" 134 : "=m" (value) : : "rax"); 135 hw_wp2: 136 report("hw watchpoint (test that dr6.BS is not set)", 137 n == 1 && 138 bp_addr[0] == ((unsigned long)&&hw_wp2) && dr6[0] == 0xffff0ff2); 139 140 n = 0; 141 set_dr6(0); 142 sw_icebp: 143 asm volatile(".byte 0xf1"); 144 report("icebp", 145 n == 1 && 146 bp_addr[0] == (unsigned long)&&sw_icebp + 1 && 147 dr6[0] == 0xffff0ff0); 148 149 return report_summary(); 150 } 151