1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdlib.h> 3 #include <unistd.h> 4 #include <sys/ioctl.h> 5 #include <linux/hw_breakpoint.h> 6 #include "tests.h" 7 #include "debug.h" 8 #include "cloexec.h" 9 #include "../perf-sys.h" 10 11 #define WP_TEST_ASSERT_VAL(fd, text, val) \ 12 do { \ 13 long long count; \ 14 wp_read(fd, &count, sizeof(long long)); \ 15 TEST_ASSERT_VAL(text, count == val); \ 16 } while (0) 17 18 volatile u64 data1; 19 volatile u8 data2[3]; 20 21 static int wp_read(int fd, long long *count, int size) 22 { 23 int ret = read(fd, count, size); 24 25 if (ret != size) { 26 pr_debug("failed to read: %d\n", ret); 27 return -1; 28 } 29 return 0; 30 } 31 32 static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type, 33 void *wp_addr, unsigned long wp_len) 34 { 35 memset(attr, 0, sizeof(struct perf_event_attr)); 36 attr->type = PERF_TYPE_BREAKPOINT; 37 attr->size = sizeof(struct perf_event_attr); 38 attr->config = 0; 39 attr->bp_type = wp_type; 40 attr->bp_addr = (unsigned long)wp_addr; 41 attr->bp_len = wp_len; 42 attr->sample_period = 1; 43 attr->sample_type = PERF_SAMPLE_IP; 44 attr->exclude_kernel = 1; 45 attr->exclude_hv = 1; 46 } 47 48 static int __event(int wp_type, void *wp_addr, unsigned long wp_len) 49 { 50 int fd; 51 struct perf_event_attr attr; 52 53 get__perf_event_attr(&attr, wp_type, wp_addr, wp_len); 54 fd = sys_perf_event_open(&attr, 0, -1, -1, 55 perf_event_open_cloexec_flag()); 56 if (fd < 0) 57 pr_debug("failed opening event %x\n", attr.bp_type); 58 59 return fd; 60 } 61 62 static int wp_ro_test(void) 63 { 64 int fd; 65 unsigned long tmp, tmp1 = rand(); 66 67 fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1)); 68 if (fd < 0) 69 return -1; 70 71 tmp = data1; 72 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 73 74 data1 = tmp1 + tmp; 75 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 76 77 close(fd); 78 return 0; 79 } 80 81 static int wp_wo_test(void) 82 { 83 int fd; 84 unsigned long tmp, tmp1 = rand(); 85 86 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 87 if (fd < 0) 88 return -1; 89 90 tmp = data1; 91 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0); 92 93 data1 = tmp1 + tmp; 94 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1); 95 96 close(fd); 97 return 0; 98 } 99 100 static int wp_rw_test(void) 101 { 102 int fd; 103 unsigned long tmp, tmp1 = rand(); 104 105 fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1, 106 sizeof(data1)); 107 if (fd < 0) 108 return -1; 109 110 tmp = data1; 111 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1); 112 113 data1 = tmp1 + tmp; 114 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2); 115 116 close(fd); 117 return 0; 118 } 119 120 static int wp_modify_test(void) 121 { 122 int fd, ret; 123 unsigned long tmp = rand(); 124 struct perf_event_attr new_attr; 125 126 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 127 if (fd < 0) 128 return -1; 129 130 data1 = tmp; 131 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 132 133 /* Modify watchpoint with disabled = 1 */ 134 get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0], 135 sizeof(u8) * 2); 136 new_attr.disabled = 1; 137 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr); 138 if (ret < 0) { 139 pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n"); 140 close(fd); 141 return ret; 142 } 143 144 data2[1] = tmp; /* Not Counted */ 145 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 146 147 /* Enable the event */ 148 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); 149 if (ret < 0) { 150 pr_debug("Failed to enable event\n"); 151 close(fd); 152 return ret; 153 } 154 155 data2[1] = tmp; /* Counted */ 156 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 157 158 data2[2] = tmp; /* Not Counted */ 159 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 160 161 close(fd); 162 return 0; 163 } 164 165 static bool wp_ro_supported(void) 166 { 167 #if defined (__x86_64__) || defined (__i386__) 168 return false; 169 #else 170 return true; 171 #endif 172 } 173 174 static void wp_ro_skip_msg(void) 175 { 176 #if defined (__x86_64__) || defined (__i386__) 177 pr_debug("Hardware does not support read only watchpoints.\n"); 178 #endif 179 } 180 181 static struct { 182 const char *desc; 183 int (*target_func)(void); 184 bool (*is_supported)(void); 185 void (*skip_msg)(void); 186 } wp_testcase_table[] = { 187 { 188 .desc = "Read Only Watchpoint", 189 .target_func = &wp_ro_test, 190 .is_supported = &wp_ro_supported, 191 .skip_msg = &wp_ro_skip_msg, 192 }, 193 { 194 .desc = "Write Only Watchpoint", 195 .target_func = &wp_wo_test, 196 }, 197 { 198 .desc = "Read / Write Watchpoint", 199 .target_func = &wp_rw_test, 200 }, 201 { 202 .desc = "Modify Watchpoint", 203 .target_func = &wp_modify_test, 204 }, 205 }; 206 207 int test__wp_subtest_get_nr(void) 208 { 209 return (int)ARRAY_SIZE(wp_testcase_table); 210 } 211 212 const char *test__wp_subtest_get_desc(int i) 213 { 214 if (i < 0 || i >= (int)ARRAY_SIZE(wp_testcase_table)) 215 return NULL; 216 return wp_testcase_table[i].desc; 217 } 218 219 int test__wp(struct test *test __maybe_unused, int i) 220 { 221 if (i < 0 || i >= (int)ARRAY_SIZE(wp_testcase_table)) 222 return TEST_FAIL; 223 224 if (wp_testcase_table[i].is_supported && 225 !wp_testcase_table[i].is_supported()) { 226 wp_testcase_table[i].skip_msg(); 227 return TEST_SKIP; 228 } 229 230 return !wp_testcase_table[i].target_func() ? TEST_OK : TEST_FAIL; 231 } 232 233 /* The s390 so far does not have support for 234 * instruction breakpoint using the perf_event_open() system call. 235 */ 236 bool test__wp_is_supported(void) 237 { 238 #if defined(__s390x__) 239 return false; 240 #else 241 return true; 242 #endif 243 } 244