1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdlib.h> 3 #include <string.h> 4 #include <unistd.h> 5 #include <errno.h> 6 #include <sys/ioctl.h> 7 #include <linux/compiler.h> 8 #include <linux/hw_breakpoint.h> 9 #include <linux/kernel.h> 10 #include "tests.h" 11 #include "debug.h" 12 #include "event.h" 13 #include "cloexec.h" 14 #include "../perf-sys.h" 15 16 #define WP_TEST_ASSERT_VAL(fd, text, val) \ 17 do { \ 18 long long count; \ 19 wp_read(fd, &count, sizeof(long long)); \ 20 TEST_ASSERT_VAL(text, count == val); \ 21 } while (0) 22 23 #ifdef __i386__ 24 /* Only breakpoint length less-than 8 has hardware support on i386. */ 25 volatile u32 data1; 26 #else 27 volatile u64 data1; 28 #endif 29 volatile u8 data2[3]; 30 31 #ifndef __s390x__ wp_read(int fd,long long * count,int size)32 static int wp_read(int fd, long long *count, int size) 33 { 34 int ret = read(fd, count, size); 35 36 if (ret != size) { 37 pr_debug("failed to read: %d\n", ret); 38 return -1; 39 } 40 return 0; 41 } 42 get__perf_event_attr(struct perf_event_attr * attr,int wp_type,void * wp_addr,unsigned long wp_len)43 static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type, 44 void *wp_addr, unsigned long wp_len) 45 { 46 memset(attr, 0, sizeof(struct perf_event_attr)); 47 attr->type = PERF_TYPE_BREAKPOINT; 48 attr->size = sizeof(struct perf_event_attr); 49 attr->config = 0; 50 attr->bp_type = wp_type; 51 attr->bp_addr = (unsigned long)wp_addr; 52 attr->bp_len = wp_len; 53 attr->sample_period = 1; 54 attr->sample_type = PERF_SAMPLE_IP; 55 attr->exclude_kernel = 1; 56 attr->exclude_hv = 1; 57 } 58 __event(int wp_type,void * wp_addr,unsigned long wp_len)59 static int __event(int wp_type, void *wp_addr, unsigned long wp_len) 60 { 61 int fd; 62 struct perf_event_attr attr; 63 64 get__perf_event_attr(&attr, wp_type, wp_addr, wp_len); 65 fd = sys_perf_event_open(&attr, 0, -1, -1, 66 perf_event_open_cloexec_flag()); 67 if (fd < 0) { 68 fd = -errno; 69 pr_debug("failed opening event %x\n", attr.bp_type); 70 } 71 72 return fd; 73 } 74 #endif 75 test__wp_ro(struct test_suite * test __maybe_unused,int subtest __maybe_unused)76 static int test__wp_ro(struct test_suite *test __maybe_unused, 77 int subtest __maybe_unused) 78 { 79 #if defined(__s390x__) || defined(__x86_64__) || defined(__i386__) 80 return TEST_SKIP; 81 #else 82 int fd; 83 unsigned long tmp, tmp1 = rand(); 84 85 fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1)); 86 if (fd < 0) 87 return fd == -ENODEV ? TEST_SKIP : -1; 88 89 tmp = data1; 90 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 91 92 data1 = tmp1 + tmp; 93 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1); 94 95 close(fd); 96 return 0; 97 #endif 98 } 99 test__wp_wo(struct test_suite * test __maybe_unused,int subtest __maybe_unused)100 static int test__wp_wo(struct test_suite *test __maybe_unused, 101 int subtest __maybe_unused) 102 { 103 #if defined(__s390x__) 104 return TEST_SKIP; 105 #else 106 int fd; 107 unsigned long tmp, tmp1 = rand(); 108 109 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 110 if (fd < 0) 111 return fd == -ENODEV ? TEST_SKIP : -1; 112 113 tmp = data1; 114 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0); 115 116 data1 = tmp1 + tmp; 117 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1); 118 119 close(fd); 120 return 0; 121 #endif 122 } 123 test__wp_rw(struct test_suite * test __maybe_unused,int subtest __maybe_unused)124 static int test__wp_rw(struct test_suite *test __maybe_unused, 125 int subtest __maybe_unused) 126 { 127 #if defined(__s390x__) 128 return TEST_SKIP; 129 #else 130 int fd; 131 unsigned long tmp, tmp1 = rand(); 132 133 fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1, 134 sizeof(data1)); 135 if (fd < 0) 136 return fd == -ENODEV ? TEST_SKIP : -1; 137 138 tmp = data1; 139 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1); 140 141 data1 = tmp1 + tmp; 142 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2); 143 144 close(fd); 145 return 0; 146 #endif 147 } 148 test__wp_modify(struct test_suite * test __maybe_unused,int subtest __maybe_unused)149 static int test__wp_modify(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 150 { 151 #if defined(__s390x__) 152 return TEST_SKIP; 153 #else 154 int fd, ret; 155 unsigned long tmp = rand(); 156 struct perf_event_attr new_attr; 157 158 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1)); 159 if (fd < 0) 160 return fd == -ENODEV ? TEST_SKIP : -1; 161 162 data1 = tmp; 163 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 164 165 /* Modify watchpoint with disabled = 1 */ 166 get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0], 167 sizeof(u8) * 2); 168 new_attr.disabled = 1; 169 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr); 170 if (ret < 0) { 171 if (errno == ENOTTY) { 172 test->test_cases[subtest].skip_reason = "missing kernel support"; 173 ret = TEST_SKIP; 174 } 175 176 pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n"); 177 close(fd); 178 return ret; 179 } 180 181 data2[1] = tmp; /* Not Counted */ 182 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1); 183 184 /* Enable the event */ 185 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); 186 if (ret < 0) { 187 pr_debug("Failed to enable event\n"); 188 close(fd); 189 return ret; 190 } 191 192 data2[1] = tmp; /* Counted */ 193 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 194 195 data2[2] = tmp; /* Not Counted */ 196 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2); 197 198 close(fd); 199 return 0; 200 #endif 201 } 202 203 static struct test_case wp_tests[] = { 204 TEST_CASE_REASON("Read Only Watchpoint", wp_ro, "missing hardware support"), 205 TEST_CASE_REASON("Write Only Watchpoint", wp_wo, "missing hardware support"), 206 TEST_CASE_REASON("Read / Write Watchpoint", wp_rw, "missing hardware support"), 207 TEST_CASE_REASON("Modify Watchpoint", wp_modify, "missing hardware support"), 208 { .name = NULL, } 209 }; 210 211 struct test_suite suite__wp = { 212 .desc = "Watchpoint", 213 .test_cases = wp_tests, 214 }; 215