1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdlib.h> 3 #include <sys/ioctl.h> 4 #include <linux/hw_breakpoint.h> 5 #include "tests.h" 6 #include "debug.h" 7 #include "cloexec.h" 8 9 #define WP_TEST_ASSERT_VAL(fd, text, val) \ 10 do { \ 11 long long count; \ 12 wp_read(fd, &count, sizeof(long long)); \ 13 TEST_ASSERT_VAL(text, count == val); \ 14 } while (0) 15 16 volatile u64 data1; 17 volatile u8 data2[3]; 18 19 static int wp_read(int fd, long long *count, int size) 20 { 21 int ret = read(fd, count, size); 22 23 if (ret != size) { 24 pr_debug("failed to read: %d\n", ret); 25 return -1; 26 } 27 return 0; 28 } 29 30 static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type, 31 void *wp_addr, unsigned long wp_len) 32 { 33 memset(attr, 0, sizeof(struct perf_event_attr)); 34 attr->type = PERF_TYPE_BREAKPOINT; 35 attr->size = sizeof(struct perf_event_attr); 36 attr->config = 0; 37 attr->bp_type = wp_type; 38 attr->bp_addr = (unsigned long)wp_addr; 39 attr->bp_len = wp_len; 40 attr->sample_period = 1; 41 attr->sample_type = PERF_SAMPLE_IP; 42 attr->exclude_kernel = 1; 43 attr->exclude_hv = 1; 44 } 45 46 static int __event(int wp_type, void *wp_addr, unsigned long wp_len) 47 { 48 int fd; 49 struct perf_event_attr attr; 50 51 get__perf_event_attr(&attr, wp_type, wp_addr, wp_len); 52 fd = sys_perf_event_open(&attr, 0, -1, -1, 53 perf_event_open_cloexec_flag()); 54 if (fd < 0) 55 pr_debug("failed opening event %x\n", attr.bp_type); 56 57 return fd; 58 } 59 60 static int wp_ro_test(void) 61 { 62 int fd; 63 unsigned long tmp, tmp1 = rand(); 64 65 fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1)); 66 if (fd < 0) 67 return -1; 68 69 tmp = data1; 70 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 71 72 data1 = tmp1 + tmp; 73 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 74 75 close(fd); 76 return 0; 77 } 78 79 static int wp_wo_test(void) 80 { 81 int fd; 82 unsigned long tmp, tmp1 = rand(); 83 84 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 85 if (fd < 0) 86 return -1; 87 88 tmp = data1; 89 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0); 90 91 data1 = tmp1 + tmp; 92 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1); 93 94 close(fd); 95 return 0; 96 } 97 98 static int wp_rw_test(void) 99 { 100 int fd; 101 unsigned long tmp, tmp1 = rand(); 102 103 fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1, 104 sizeof(data1)); 105 if (fd < 0) 106 return -1; 107 108 tmp = data1; 109 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1); 110 111 data1 = tmp1 + tmp; 112 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2); 113 114 close(fd); 115 return 0; 116 } 117 118 static int wp_modify_test(void) 119 { 120 int fd, ret; 121 unsigned long tmp = rand(); 122 struct perf_event_attr new_attr; 123 124 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 125 if (fd < 0) 126 return -1; 127 128 data1 = tmp; 129 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 130 131 /* Modify watchpoint with disabled = 1 */ 132 get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0], 133 sizeof(u8) * 2); 134 new_attr.disabled = 1; 135 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr); 136 if (ret < 0) { 137 pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n"); 138 close(fd); 139 return ret; 140 } 141 142 data2[1] = tmp; /* Not Counted */ 143 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 144 145 /* Enable the event */ 146 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); 147 if (ret < 0) { 148 pr_debug("Failed to enable event\n"); 149 close(fd); 150 return ret; 151 } 152 153 data2[1] = tmp; /* Counted */ 154 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 155 156 data2[2] = tmp; /* Not Counted */ 157 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 158 159 close(fd); 160 return 0; 161 } 162 163 static bool wp_ro_supported(void) 164 { 165 #if defined (__x86_64__) || defined (__i386__) 166 return false; 167 #else 168 return true; 169 #endif 170 } 171 172 static void wp_ro_skip_msg(void) 173 { 174 #if defined (__x86_64__) || defined (__i386__) 175 pr_debug("Hardware does not support read only watchpoints.\n"); 176 #endif 177 } 178 179 static struct { 180 const char *desc; 181 int (*target_func)(void); 182 bool (*is_supported)(void); 183 void (*skip_msg)(void); 184 } wp_testcase_table[] = { 185 { 186 .desc = "Read Only Watchpoint", 187 .target_func = &wp_ro_test, 188 .is_supported = &wp_ro_supported, 189 .skip_msg = &wp_ro_skip_msg, 190 }, 191 { 192 .desc = "Write Only Watchpoint", 193 .target_func = &wp_wo_test, 194 }, 195 { 196 .desc = "Read / Write Watchpoint", 197 .target_func = &wp_rw_test, 198 }, 199 { 200 .desc = "Modify Watchpoint", 201 .target_func = &wp_modify_test, 202 }, 203 }; 204 205 int test__wp_subtest_get_nr(void) 206 { 207 return (int)ARRAY_SIZE(wp_testcase_table); 208 } 209 210 const char *test__wp_subtest_get_desc(int i) 211 { 212 if (i < 0 || i >= (int)ARRAY_SIZE(wp_testcase_table)) 213 return NULL; 214 return wp_testcase_table[i].desc; 215 } 216 217 int test__wp(struct test *test __maybe_unused, int i) 218 { 219 if (i < 0 || i >= (int)ARRAY_SIZE(wp_testcase_table)) 220 return TEST_FAIL; 221 222 if (wp_testcase_table[i].is_supported && 223 !wp_testcase_table[i].is_supported()) { 224 wp_testcase_table[i].skip_msg(); 225 return TEST_SKIP; 226 } 227 228 return !wp_testcase_table[i].target_func() ? TEST_OK : TEST_FAIL; 229 } 230 231 /* The s390 so far does not have support for 232 * instruction breakpoint using the perf_event_open() system call. 233 */ 234 bool test__wp_is_supported(void) 235 { 236 #if defined(__s390x__) 237 return false; 238 #else 239 return true; 240 #endif 241 } 242