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40#include <linux/list.h>
41#include <linux/module.h>
42#include <linux/kernel.h>
43#include <linux/bug.h>
44#include <linux/sched.h>
45
46extern const struct bug_entry __start___bug_table[], __stop___bug_table[];
47
48static inline unsigned long bug_addr(const struct bug_entry *bug)
49{
50#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
51 return bug->bug_addr;
52#else
53 return (unsigned long)bug + bug->bug_addr_disp;
54#endif
55}
56
57#ifdef CONFIG_MODULES
58
59static LIST_HEAD(module_bug_list);
60
61static const struct bug_entry *module_find_bug(unsigned long bugaddr)
62{
63 struct module *mod;
64
65 list_for_each_entry(mod, &module_bug_list, bug_list) {
66 const struct bug_entry *bug = mod->bug_table;
67 unsigned i;
68
69 for (i = 0; i < mod->num_bugs; ++i, ++bug)
70 if (bugaddr == bug_addr(bug))
71 return bug;
72 }
73 return NULL;
74}
75
76void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
77 struct module *mod)
78{
79 char *secstrings;
80 unsigned int i;
81
82 mod->bug_table = NULL;
83 mod->num_bugs = 0;
84
85
86 secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
87 for (i = 1; i < hdr->e_shnum; i++) {
88 if (strcmp(secstrings+sechdrs[i].sh_name, "__bug_table"))
89 continue;
90 mod->bug_table = (void *) sechdrs[i].sh_addr;
91 mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry);
92 break;
93 }
94
95
96
97
98
99
100 list_add(&mod->bug_list, &module_bug_list);
101}
102
103void module_bug_cleanup(struct module *mod)
104{
105 list_del(&mod->bug_list);
106}
107
108#else
109
110static inline const struct bug_entry *module_find_bug(unsigned long bugaddr)
111{
112 return NULL;
113}
114#endif
115
116const struct bug_entry *find_bug(unsigned long bugaddr)
117{
118 const struct bug_entry *bug;
119
120 for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
121 if (bugaddr == bug_addr(bug))
122 return bug;
123
124 return module_find_bug(bugaddr);
125}
126
127enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
128{
129 const struct bug_entry *bug;
130 const char *file;
131 unsigned line, warning;
132
133 if (!is_valid_bugaddr(bugaddr))
134 return BUG_TRAP_TYPE_NONE;
135
136 bug = find_bug(bugaddr);
137
138 file = NULL;
139 line = 0;
140 warning = 0;
141
142 if (bug) {
143#ifdef CONFIG_DEBUG_BUGVERBOSE
144#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
145 file = bug->file;
146#else
147 file = (const char *)bug + bug->file_disp;
148#endif
149 line = bug->line;
150#endif
151 warning = (bug->flags & BUGFLAG_WARNING) != 0;
152 }
153
154 if (warning) {
155
156 printk(KERN_WARNING "------------[ cut here ]------------\n");
157
158 if (file)
159 printk(KERN_WARNING "WARNING: at %s:%u\n",
160 file, line);
161 else
162 printk(KERN_WARNING "WARNING: at %p "
163 "[verbose debug info unavailable]\n",
164 (void *)bugaddr);
165
166 print_modules();
167 show_regs(regs);
168 print_oops_end_marker();
169
170 add_taint(BUG_GET_TAINT(bug), LOCKDEP_STILL_OK);
171 return BUG_TRAP_TYPE_WARN;
172 }
173
174 printk(KERN_DEFAULT "------------[ cut here ]------------\n");
175
176 if (file)
177 printk(KERN_CRIT "kernel BUG at %s:%u!\n",
178 file, line);
179 else
180 printk(KERN_CRIT "Kernel BUG at %p "
181 "[verbose debug info unavailable]\n",
182 (void *)bugaddr);
183
184 return BUG_TRAP_TYPE_BUG;
185}
186