This source file includes following definitions.
- bug_addr
- module_find_bug
- module_bug_finalize
- module_bug_cleanup
- module_find_bug
- find_bug
- report_bug
- clear_once_table
- generic_bug_clear_once
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42 #define pr_fmt(fmt) fmt
43
44 #include <linux/list.h>
45 #include <linux/module.h>
46 #include <linux/kernel.h>
47 #include <linux/bug.h>
48 #include <linux/sched.h>
49 #include <linux/rculist.h>
50
51 extern struct bug_entry __start___bug_table[], __stop___bug_table[];
52
53 static inline unsigned long bug_addr(const struct bug_entry *bug)
54 {
55 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
56 return bug->bug_addr;
57 #else
58 return (unsigned long)bug + bug->bug_addr_disp;
59 #endif
60 }
61
62 #ifdef CONFIG_MODULES
63
64 static LIST_HEAD(module_bug_list);
65
66 static struct bug_entry *module_find_bug(unsigned long bugaddr)
67 {
68 struct module *mod;
69 struct bug_entry *bug = NULL;
70
71 rcu_read_lock_sched();
72 list_for_each_entry_rcu(mod, &module_bug_list, bug_list) {
73 unsigned i;
74
75 bug = mod->bug_table;
76 for (i = 0; i < mod->num_bugs; ++i, ++bug)
77 if (bugaddr == bug_addr(bug))
78 goto out;
79 }
80 bug = NULL;
81 out:
82 rcu_read_unlock_sched();
83
84 return bug;
85 }
86
87 void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
88 struct module *mod)
89 {
90 char *secstrings;
91 unsigned int i;
92
93 lockdep_assert_held(&module_mutex);
94
95 mod->bug_table = NULL;
96 mod->num_bugs = 0;
97
98
99 secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
100 for (i = 1; i < hdr->e_shnum; i++) {
101 if (strcmp(secstrings+sechdrs[i].sh_name, "__bug_table"))
102 continue;
103 mod->bug_table = (void *) sechdrs[i].sh_addr;
104 mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry);
105 break;
106 }
107
108
109
110
111
112
113
114
115 list_add_rcu(&mod->bug_list, &module_bug_list);
116 }
117
118 void module_bug_cleanup(struct module *mod)
119 {
120 lockdep_assert_held(&module_mutex);
121 list_del_rcu(&mod->bug_list);
122 }
123
124 #else
125
126 static inline struct bug_entry *module_find_bug(unsigned long bugaddr)
127 {
128 return NULL;
129 }
130 #endif
131
132 struct bug_entry *find_bug(unsigned long bugaddr)
133 {
134 struct bug_entry *bug;
135
136 for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
137 if (bugaddr == bug_addr(bug))
138 return bug;
139
140 return module_find_bug(bugaddr);
141 }
142
143 enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
144 {
145 struct bug_entry *bug;
146 const char *file;
147 unsigned line, warning, once, done;
148
149 if (!is_valid_bugaddr(bugaddr))
150 return BUG_TRAP_TYPE_NONE;
151
152 bug = find_bug(bugaddr);
153 if (!bug)
154 return BUG_TRAP_TYPE_NONE;
155
156 file = NULL;
157 line = 0;
158 warning = 0;
159
160 if (bug) {
161 #ifdef CONFIG_DEBUG_BUGVERBOSE
162 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
163 file = bug->file;
164 #else
165 file = (const char *)bug + bug->file_disp;
166 #endif
167 line = bug->line;
168 #endif
169 warning = (bug->flags & BUGFLAG_WARNING) != 0;
170 once = (bug->flags & BUGFLAG_ONCE) != 0;
171 done = (bug->flags & BUGFLAG_DONE) != 0;
172
173 if (warning && once) {
174 if (done)
175 return BUG_TRAP_TYPE_WARN;
176
177
178
179
180 bug->flags |= BUGFLAG_DONE;
181 }
182 }
183
184
185
186
187
188
189
190 if ((bug->flags & BUGFLAG_NO_CUT_HERE) == 0)
191 printk(KERN_DEFAULT CUT_HERE);
192
193 if (warning) {
194
195 __warn(file, line, (void *)bugaddr, BUG_GET_TAINT(bug), regs,
196 NULL);
197 return BUG_TRAP_TYPE_WARN;
198 }
199
200 if (file)
201 pr_crit("kernel BUG at %s:%u!\n", file, line);
202 else
203 pr_crit("Kernel BUG at %pB [verbose debug info unavailable]\n",
204 (void *)bugaddr);
205
206 return BUG_TRAP_TYPE_BUG;
207 }
208
209 static void clear_once_table(struct bug_entry *start, struct bug_entry *end)
210 {
211 struct bug_entry *bug;
212
213 for (bug = start; bug < end; bug++)
214 bug->flags &= ~BUGFLAG_DONE;
215 }
216
217 void generic_bug_clear_once(void)
218 {
219 #ifdef CONFIG_MODULES
220 struct module *mod;
221
222 rcu_read_lock_sched();
223 list_for_each_entry_rcu(mod, &module_bug_list, bug_list)
224 clear_once_table(mod->bug_table,
225 mod->bug_table + mod->num_bugs);
226 rcu_read_unlock_sched();
227 #endif
228
229 clear_once_table(__start___bug_table, __stop___bug_table);
230 }