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5#include <linux/kallsyms.h>
6#include <linux/kprobes.h>
7#include <linux/uaccess.h>
8#include <linux/utsname.h>
9#include <linux/hardirq.h>
10#include <linux/kdebug.h>
11#include <linux/module.h>
12#include <linux/ptrace.h>
13#include <linux/kexec.h>
14#include <linux/bug.h>
15#include <linux/nmi.h>
16#include <linux/sysfs.h>
17
18#include <asm/stacktrace.h>
19
20#define STACKSLOTS_PER_LINE 8
21#define get_bp(bp) asm("movl %%ebp, %0" : "=r" (bp) :)
22
23int panic_on_unrecovered_nmi;
24int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
25static unsigned int code_bytes = 64;
26static int die_counter;
27
28void printk_address(unsigned long address, int reliable)
29{
30 printk(" [<%p>] %s%pS\n", (void *) address,
31 reliable ? "" : "? ", (void *) address);
32}
33
34static inline int valid_stack_ptr(struct thread_info *tinfo,
35 void *p, unsigned int size, void *end)
36{
37 void *t = tinfo;
38 if (end) {
39 if (p < end && p >= (end-THREAD_SIZE))
40 return 1;
41 else
42 return 0;
43 }
44 return p > t && p < t + THREAD_SIZE - size;
45}
46
47
48struct stack_frame {
49 struct stack_frame *next_frame;
50 unsigned long return_address;
51};
52
53static inline unsigned long
54print_context_stack(struct thread_info *tinfo,
55 unsigned long *stack, unsigned long bp,
56 const struct stacktrace_ops *ops, void *data,
57 unsigned long *end)
58{
59 struct stack_frame *frame = (struct stack_frame *)bp;
60
61 while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
62 unsigned long addr;
63
64 addr = *stack;
65 if (__kernel_text_address(addr)) {
66 if ((unsigned long) stack == bp + sizeof(long)) {
67 ops->address(data, addr, 1);
68 frame = frame->next_frame;
69 bp = (unsigned long) frame;
70 } else {
71 ops->address(data, addr, bp == 0);
72 }
73 }
74 stack++;
75 }
76 return bp;
77}
78
79void dump_trace(struct task_struct *task, struct pt_regs *regs,
80 unsigned long *stack, unsigned long bp,
81 const struct stacktrace_ops *ops, void *data)
82{
83 if (!task)
84 task = current;
85
86 if (!stack) {
87 unsigned long dummy;
88 stack = &dummy;
89 if (task && task != current)
90 stack = (unsigned long *)task->thread.sp;
91 }
92
93#ifdef CONFIG_FRAME_POINTER
94 if (!bp) {
95 if (task == current) {
96
97 get_bp(bp);
98 } else {
99
100 bp = *(unsigned long *) task->thread.sp;
101 }
102 }
103#endif
104
105 for (;;) {
106 struct thread_info *context;
107
108 context = (struct thread_info *)
109 ((unsigned long)stack & (~(THREAD_SIZE - 1)));
110 bp = print_context_stack(context, stack, bp, ops, data, NULL);
111
112 stack = (unsigned long *)context->previous_esp;
113 if (!stack)
114 break;
115 if (ops->stack(data, "IRQ") < 0)
116 break;
117 touch_nmi_watchdog();
118 }
119}
120EXPORT_SYMBOL(dump_trace);
121
122static void
123print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
124{
125 printk(data);
126 print_symbol(msg, symbol);
127 printk("\n");
128}
129
130static void print_trace_warning(void *data, char *msg)
131{
132 printk("%s%s\n", (char *)data, msg);
133}
134
135static int print_trace_stack(void *data, char *name)
136{
137 printk("%s <%s> ", (char *)data, name);
138 return 0;
139}
140
141
142
143
144static void print_trace_address(void *data, unsigned long addr, int reliable)
145{
146 touch_nmi_watchdog();
147 printk(data);
148 printk_address(addr, reliable);
149}
150
151static const struct stacktrace_ops print_trace_ops = {
152 .warning = print_trace_warning,
153 .warning_symbol = print_trace_warning_symbol,
154 .stack = print_trace_stack,
155 .address = print_trace_address,
156};
157
158static void
159show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
160 unsigned long *stack, unsigned long bp, char *log_lvl)
161{
162 printk("%sCall Trace:\n", log_lvl);
163 dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
164}
165
166void show_trace(struct task_struct *task, struct pt_regs *regs,
167 unsigned long *stack, unsigned long bp)
168{
169 show_trace_log_lvl(task, regs, stack, bp, "");
170}
171
172static void
173show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
174 unsigned long *sp, unsigned long bp, char *log_lvl)
175{
176 unsigned long *stack;
177 int i;
178
179 if (sp == NULL) {
180 if (task)
181 sp = (unsigned long *)task->thread.sp;
182 else
183 sp = (unsigned long *)&sp;
184 }
185
186 stack = sp;
187 for (i = 0; i < kstack_depth_to_print; i++) {
188 if (kstack_end(stack))
189 break;
190 if (i && ((i % STACKSLOTS_PER_LINE) == 0))
191 printk("\n%s", log_lvl);
192 printk(" %08lx", *stack++);
193 touch_nmi_watchdog();
194 }
195 printk("\n");
196 show_trace_log_lvl(task, regs, sp, bp, log_lvl);
197}
198
199void show_stack(struct task_struct *task, unsigned long *sp)
200{
201 show_stack_log_lvl(task, NULL, sp, 0, "");
202}
203
204
205
206
207void dump_stack(void)
208{
209 unsigned long bp = 0;
210 unsigned long stack;
211
212#ifdef CONFIG_FRAME_POINTER
213 if (!bp)
214 get_bp(bp);
215#endif
216
217 printk("Pid: %d, comm: %.20s %s %s %.*s\n",
218 current->pid, current->comm, print_tainted(),
219 init_utsname()->release,
220 (int)strcspn(init_utsname()->version, " "),
221 init_utsname()->version);
222 show_trace(NULL, NULL, &stack, bp);
223}
224
225EXPORT_SYMBOL(dump_stack);
226
227void show_registers(struct pt_regs *regs)
228{
229 int i;
230
231 print_modules();
232 __show_regs(regs, 0);
233
234 printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n",
235 TASK_COMM_LEN, current->comm, task_pid_nr(current),
236 current_thread_info(), current, task_thread_info(current));
237
238
239
240
241 if (!user_mode_vm(regs)) {
242 unsigned int code_prologue = code_bytes * 43 / 64;
243 unsigned int code_len = code_bytes;
244 unsigned char c;
245 u8 *ip;
246
247 printk(KERN_EMERG "Stack:\n");
248 show_stack_log_lvl(NULL, regs, ®s->sp,
249 0, KERN_EMERG);
250
251 printk(KERN_EMERG "Code: ");
252
253 ip = (u8 *)regs->ip - code_prologue;
254 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
255
256 ip = (u8 *)regs->ip;
257 code_len = code_len - code_prologue + 1;
258 }
259 for (i = 0; i < code_len; i++, ip++) {
260 if (ip < (u8 *)PAGE_OFFSET ||
261 probe_kernel_address(ip, c)) {
262 printk(" Bad EIP value.");
263 break;
264 }
265 if (ip == (u8 *)regs->ip)
266 printk("<%02x> ", c);
267 else
268 printk("%02x ", c);
269 }
270 }
271 printk("\n");
272}
273
274int is_valid_bugaddr(unsigned long ip)
275{
276 unsigned short ud2;
277
278 if (ip < PAGE_OFFSET)
279 return 0;
280 if (probe_kernel_address((unsigned short *)ip, ud2))
281 return 0;
282
283 return ud2 == 0x0b0f;
284}
285
286static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
287static int die_owner = -1;
288static unsigned int die_nest_count;
289
290unsigned __kprobes long oops_begin(void)
291{
292 unsigned long flags;
293
294 oops_enter();
295
296 if (die_owner != raw_smp_processor_id()) {
297 console_verbose();
298 raw_local_irq_save(flags);
299 __raw_spin_lock(&die_lock);
300 die_owner = smp_processor_id();
301 die_nest_count = 0;
302 bust_spinlocks(1);
303 } else {
304 raw_local_irq_save(flags);
305 }
306 die_nest_count++;
307 return flags;
308}
309
310void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
311{
312 bust_spinlocks(0);
313 die_owner = -1;
314 add_taint(TAINT_DIE);
315 __raw_spin_unlock(&die_lock);
316 raw_local_irq_restore(flags);
317
318 if (!regs)
319 return;
320
321 if (kexec_should_crash(current))
322 crash_kexec(regs);
323 if (in_interrupt())
324 panic("Fatal exception in interrupt");
325 if (panic_on_oops)
326 panic("Fatal exception");
327 oops_exit();
328 do_exit(signr);
329}
330
331int __kprobes __die(const char *str, struct pt_regs *regs, long err)
332{
333 unsigned short ss;
334 unsigned long sp;
335
336 printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
337#ifdef CONFIG_PREEMPT
338 printk("PREEMPT ");
339#endif
340#ifdef CONFIG_SMP
341 printk("SMP ");
342#endif
343#ifdef CONFIG_DEBUG_PAGEALLOC
344 printk("DEBUG_PAGEALLOC");
345#endif
346 printk("\n");
347 sysfs_printk_last_file();
348 if (notify_die(DIE_OOPS, str, regs, err,
349 current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
350 return 1;
351
352 show_registers(regs);
353
354 sp = (unsigned long) (®s->sp);
355 savesegment(ss, ss);
356 if (user_mode(regs)) {
357 sp = regs->sp;
358 ss = regs->ss & 0xffff;
359 }
360 printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
361 print_symbol("%s", regs->ip);
362 printk(" SS:ESP %04x:%08lx\n", ss, sp);
363 return 0;
364}
365
366
367
368
369
370void die(const char *str, struct pt_regs *regs, long err)
371{
372 unsigned long flags = oops_begin();
373
374 if (die_nest_count < 3) {
375 report_bug(regs->ip, regs);
376
377 if (__die(str, regs, err))
378 regs = NULL;
379 } else {
380 printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
381 }
382
383 oops_end(flags, regs, SIGSEGV);
384}
385
386static DEFINE_SPINLOCK(nmi_print_lock);
387
388void notrace __kprobes
389die_nmi(char *str, struct pt_regs *regs, int do_panic)
390{
391 if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
392 return;
393
394 spin_lock(&nmi_print_lock);
395
396
397
398
399 bust_spinlocks(1);
400 printk(KERN_EMERG "%s", str);
401 printk(" on CPU%d, ip %08lx, registers:\n",
402 smp_processor_id(), regs->ip);
403 show_registers(regs);
404 if (do_panic)
405 panic("Non maskable interrupt");
406 console_silent();
407 spin_unlock(&nmi_print_lock);
408
409
410
411
412
413 if (!user_mode_vm(regs)) {
414 current->thread.trap_no = 2;
415 crash_kexec(regs);
416 }
417
418 bust_spinlocks(0);
419 do_exit(SIGSEGV);
420}
421
422static int __init oops_setup(char *s)
423{
424 if (!s)
425 return -EINVAL;
426 if (!strcmp(s, "panic"))
427 panic_on_oops = 1;
428 return 0;
429}
430early_param("oops", oops_setup);
431
432static int __init kstack_setup(char *s)
433{
434 if (!s)
435 return -EINVAL;
436 kstack_depth_to_print = simple_strtoul(s, NULL, 0);
437 return 0;
438}
439early_param("kstack", kstack_setup);
440
441static int __init code_bytes_setup(char *s)
442{
443 code_bytes = simple_strtoul(s, NULL, 0);
444 if (code_bytes > 8192)
445 code_bytes = 8192;
446
447 return 1;
448}
449__setup("code_bytes=", code_bytes_setup);
450
