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15#include <linux/module.h>
16#include <linux/signal.h>
17#include <linux/spinlock.h>
18#include <linux/personality.h>
19#include <linux/kallsyms.h>
20#include <linux/kdebug.h>
21#include <linux/uaccess.h>
22#include <linux/delay.h>
23#include <linux/hardirq.h>
24#include <linux/init.h>
25#include <linux/atomic.h>
26#include <linux/unistd.h>
27
28#include <asm/cacheflush.h>
29#include <asm/traps.h>
30
31#include "setup.h"
32
33static void dump_mem(const char *, const char *, unsigned long, unsigned long);
34
35void dump_backtrace_entry(unsigned long where,
36 unsigned long from, unsigned long frame)
37{
38#ifdef CONFIG_KALLSYMS
39 printk(KERN_DEFAULT "[<%08lx>] (%pS) from [<%08lx>] (%pS)\n",
40 where, (void *)where, from, (void *)from);
41#else
42 printk(KERN_DEFAULT "Function entered at [<%08lx>] from [<%08lx>]\n",
43 where, from);
44#endif
45}
46
47
48
49
50
51
52static int verify_stack(unsigned long sp)
53{
54 if (sp < PAGE_OFFSET ||
55 (sp > (unsigned long)high_memory && high_memory != NULL))
56 return -EFAULT;
57
58 return 0;
59}
60
61
62
63
64static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
65 unsigned long top)
66{
67 unsigned long first;
68 mm_segment_t fs;
69 int i;
70
71
72
73
74
75
76 fs = get_fs();
77 set_fs(KERNEL_DS);
78
79 printk(KERN_DEFAULT "%s%s(0x%08lx to 0x%08lx)\n",
80 lvl, str, bottom, top);
81
82 for (first = bottom & ~31; first < top; first += 32) {
83 unsigned long p;
84 char str[sizeof(" 12345678") * 8 + 1];
85
86 memset(str, ' ', sizeof(str));
87 str[sizeof(str) - 1] = '\0';
88
89 for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
90 if (p >= bottom && p < top) {
91 unsigned long val;
92 if (__get_user(val, (unsigned long *)p) == 0)
93 sprintf(str + i * 9, " %08lx", val);
94 else
95 sprintf(str + i * 9, " ????????");
96 }
97 }
98 printk(KERN_DEFAULT "%s%04lx:%s\n", lvl, first & 0xffff, str);
99 }
100
101 set_fs(fs);
102}
103
104static void dump_instr(const char *lvl, struct pt_regs *regs)
105{
106 unsigned long addr = instruction_pointer(regs);
107 const int width = 8;
108 mm_segment_t fs;
109 char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
110 int i;
111
112
113
114
115
116
117 fs = get_fs();
118 set_fs(KERNEL_DS);
119
120 for (i = -4; i < 1; i++) {
121 unsigned int val, bad;
122
123 bad = __get_user(val, &((u32 *)addr)[i]);
124
125 if (!bad)
126 p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ",
127 width, val);
128 else {
129 p += sprintf(p, "bad PC value");
130 break;
131 }
132 }
133 printk(KERN_DEFAULT "%sCode: %s\n", lvl, str);
134
135 set_fs(fs);
136}
137
138static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
139{
140 unsigned int fp, mode;
141 int ok = 1;
142
143 printk(KERN_DEFAULT "Backtrace: ");
144
145 if (!tsk)
146 tsk = current;
147
148 if (regs) {
149 fp = regs->UCreg_fp;
150 mode = processor_mode(regs);
151 } else if (tsk != current) {
152 fp = thread_saved_fp(tsk);
153 mode = 0x10;
154 } else {
155 asm("mov %0, fp" : "=r" (fp) : : "cc");
156 mode = 0x10;
157 }
158
159 if (!fp) {
160 printk("no frame pointer");
161 ok = 0;
162 } else if (verify_stack(fp)) {
163 printk("invalid frame pointer 0x%08x", fp);
164 ok = 0;
165 } else if (fp < (unsigned long)end_of_stack(tsk))
166 printk("frame pointer underflow");
167 printk("\n");
168
169 if (ok)
170 c_backtrace(fp, mode);
171}
172
173void show_stack(struct task_struct *tsk, unsigned long *sp)
174{
175 dump_backtrace(NULL, tsk);
176 barrier();
177}
178
179static int __die(const char *str, int err, struct thread_info *thread,
180 struct pt_regs *regs)
181{
182 struct task_struct *tsk = thread->task;
183 static int die_counter;
184 int ret;
185
186 printk(KERN_EMERG "Internal error: %s: %x [#%d]\n",
187 str, err, ++die_counter);
188
189
190 ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, \
191 SIGSEGV);
192 if (ret == NOTIFY_STOP)
193 return ret;
194
195 print_modules();
196 __show_regs(regs);
197 printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n",
198 TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
199
200 if (!user_mode(regs) || in_interrupt()) {
201 dump_mem(KERN_EMERG, "Stack: ", regs->UCreg_sp,
202 THREAD_SIZE + (unsigned long)task_stack_page(tsk));
203 dump_backtrace(regs, tsk);
204 dump_instr(KERN_EMERG, regs);
205 }
206
207 return ret;
208}
209
210DEFINE_SPINLOCK(die_lock);
211
212
213
214
215void die(const char *str, struct pt_regs *regs, int err)
216{
217 struct thread_info *thread = current_thread_info();
218 int ret;
219
220 oops_enter();
221
222 spin_lock_irq(&die_lock);
223 console_verbose();
224 bust_spinlocks(1);
225 ret = __die(str, err, thread, regs);
226
227 bust_spinlocks(0);
228 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
229 spin_unlock_irq(&die_lock);
230 oops_exit();
231
232 if (in_interrupt())
233 panic("Fatal exception in interrupt");
234 if (panic_on_oops)
235 panic("Fatal exception");
236 if (ret != NOTIFY_STOP)
237 do_exit(SIGSEGV);
238}
239
240void uc32_notify_die(const char *str, struct pt_regs *regs,
241 struct siginfo *info, unsigned long err, unsigned long trap)
242{
243 if (user_mode(regs)) {
244 current->thread.error_code = err;
245 current->thread.trap_no = trap;
246
247 force_sig_info(info->si_signo, info, current);
248 } else
249 die(str, regs, err);
250}
251
252
253
254
255
256
257
258asmlinkage void bad_mode(struct pt_regs *regs, unsigned int reason)
259{
260 console_verbose();
261
262 printk(KERN_CRIT "Bad mode detected with reason 0x%x\n", reason);
263
264 die("Oops - bad mode", regs, 0);
265 local_irq_disable();
266 panic("bad mode");
267}
268
269void __pte_error(const char *file, int line, unsigned long val)
270{
271 printk(KERN_DEFAULT "%s:%d: bad pte %08lx.\n", file, line, val);
272}
273
274void __pmd_error(const char *file, int line, unsigned long val)
275{
276 printk(KERN_DEFAULT "%s:%d: bad pmd %08lx.\n", file, line, val);
277}
278
279void __pgd_error(const char *file, int line, unsigned long val)
280{
281 printk(KERN_DEFAULT "%s:%d: bad pgd %08lx.\n", file, line, val);
282}
283
284asmlinkage void __div0(void)
285{
286 printk(KERN_DEFAULT "Division by zero in kernel.\n");
287 dump_stack();
288}
289EXPORT_SYMBOL(__div0);
290
291void abort(void)
292{
293 BUG();
294
295
296 panic("Oops failed to kill thread");
297}
298EXPORT_SYMBOL(abort);
299
300void __init trap_init(void)
301{
302 return;
303}
304
305void __init early_trap_init(void)
306{
307 unsigned long vectors = VECTORS_BASE;
308
309
310
311
312
313
314 memcpy((void *)vectors,
315 __vectors_start,
316 __vectors_end - __vectors_start);
317 memcpy((void *)vectors + 0x200,
318 __stubs_start,
319 __stubs_end - __stubs_start);
320
321 early_signal_init();
322
323 flush_icache_range(vectors, vectors + PAGE_SIZE);
324}
325