Commit | Line | Data |
---|---|---|
2bc5f927 AH |
1 | /* |
2 | * Copyright (C) 1991, 1992 Linus Torvalds | |
3 | * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs | |
4 | */ | |
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 | ||
17 | #include <asm/stacktrace.h> | |
18 | ||
8a541665 AH |
19 | #define STACKSLOTS_PER_LINE 8 |
20 | #define get_bp(bp) asm("movl %%ebp, %0" : "=r" (bp) :) | |
21 | ||
2bc5f927 | 22 | int panic_on_unrecovered_nmi; |
8a541665 | 23 | int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; |
2bc5f927 AH |
24 | static unsigned int code_bytes = 64; |
25 | static int die_counter; | |
26 | ||
27 | void printk_address(unsigned long address, int reliable) | |
28 | { | |
16182790 AH |
29 | printk(" [<%p>] %s%pS\n", (void *) address, |
30 | reliable ? "" : "? ", (void *) address); | |
2bc5f927 AH |
31 | } |
32 | ||
33 | static inline int valid_stack_ptr(struct thread_info *tinfo, | |
3a18512d | 34 | void *p, unsigned int size, void *end) |
2bc5f927 AH |
35 | { |
36 | void *t = tinfo; | |
3a18512d AH |
37 | if (end) { |
38 | if (p < end && p >= (end-THREAD_SIZE)) | |
39 | return 1; | |
40 | else | |
41 | return 0; | |
42 | } | |
43 | return p > t && p < t + THREAD_SIZE - size; | |
2bc5f927 AH |
44 | } |
45 | ||
46 | /* The form of the top of the frame on the stack */ | |
47 | struct stack_frame { | |
48 | struct stack_frame *next_frame; | |
49 | unsigned long return_address; | |
50 | }; | |
51 | ||
52 | static inline unsigned long | |
53 | print_context_stack(struct thread_info *tinfo, | |
54 | unsigned long *stack, unsigned long bp, | |
3a18512d AH |
55 | const struct stacktrace_ops *ops, void *data, |
56 | unsigned long *end) | |
2bc5f927 AH |
57 | { |
58 | struct stack_frame *frame = (struct stack_frame *)bp; | |
59 | ||
3a18512d | 60 | while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) { |
2bc5f927 AH |
61 | unsigned long addr; |
62 | ||
63 | addr = *stack; | |
64 | if (__kernel_text_address(addr)) { | |
3a18512d | 65 | if ((unsigned long) stack == bp + sizeof(long)) { |
2bc5f927 AH |
66 | ops->address(data, addr, 1); |
67 | frame = frame->next_frame; | |
68 | bp = (unsigned long) frame; | |
69 | } else { | |
70 | ops->address(data, addr, bp == 0); | |
71 | } | |
72 | } | |
73 | stack++; | |
74 | } | |
75 | return bp; | |
76 | } | |
77 | ||
78 | void dump_trace(struct task_struct *task, struct pt_regs *regs, | |
79 | unsigned long *stack, unsigned long bp, | |
80 | const struct stacktrace_ops *ops, void *data) | |
81 | { | |
82 | if (!task) | |
83 | task = current; | |
84 | ||
85 | if (!stack) { | |
86 | unsigned long dummy; | |
87 | stack = &dummy; | |
8a541665 | 88 | if (task && task != current) |
2bc5f927 AH |
89 | stack = (unsigned long *)task->thread.sp; |
90 | } | |
91 | ||
92 | #ifdef CONFIG_FRAME_POINTER | |
93 | if (!bp) { | |
94 | if (task == current) { | |
95 | /* Grab bp right from our regs */ | |
8a541665 | 96 | get_bp(bp); |
2bc5f927 AH |
97 | } else { |
98 | /* bp is the last reg pushed by switch_to */ | |
99 | bp = *(unsigned long *) task->thread.sp; | |
100 | } | |
101 | } | |
102 | #endif | |
103 | ||
104 | for (;;) { | |
105 | struct thread_info *context; | |
106 | ||
107 | context = (struct thread_info *) | |
108 | ((unsigned long)stack & (~(THREAD_SIZE - 1))); | |
3a18512d | 109 | bp = print_context_stack(context, stack, bp, ops, data, NULL); |
2ac53721 | 110 | |
2bc5f927 AH |
111 | stack = (unsigned long *)context->previous_esp; |
112 | if (!stack) | |
113 | break; | |
2ac53721 AH |
114 | if (ops->stack(data, "IRQ") < 0) |
115 | break; | |
2bc5f927 AH |
116 | touch_nmi_watchdog(); |
117 | } | |
118 | } | |
119 | EXPORT_SYMBOL(dump_trace); | |
120 | ||
121 | static void | |
122 | print_trace_warning_symbol(void *data, char *msg, unsigned long symbol) | |
123 | { | |
124 | printk(data); | |
125 | print_symbol(msg, symbol); | |
126 | printk("\n"); | |
127 | } | |
128 | ||
129 | static void print_trace_warning(void *data, char *msg) | |
130 | { | |
131 | printk("%s%s\n", (char *)data, msg); | |
132 | } | |
133 | ||
134 | static int print_trace_stack(void *data, char *name) | |
135 | { | |
2ac53721 | 136 | printk("%s <%s> ", (char *)data, name); |
2bc5f927 AH |
137 | return 0; |
138 | } | |
139 | ||
140 | /* | |
141 | * Print one address/symbol entries per line. | |
142 | */ | |
143 | static void print_trace_address(void *data, unsigned long addr, int reliable) | |
144 | { | |
2bc5f927 | 145 | touch_nmi_watchdog(); |
2ac53721 AH |
146 | printk(data); |
147 | printk_address(addr, reliable); | |
2bc5f927 AH |
148 | } |
149 | ||
150 | static const struct stacktrace_ops print_trace_ops = { | |
151 | .warning = print_trace_warning, | |
152 | .warning_symbol = print_trace_warning_symbol, | |
153 | .stack = print_trace_stack, | |
154 | .address = print_trace_address, | |
155 | }; | |
156 | ||
157 | static void | |
158 | show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, | |
159 | unsigned long *stack, unsigned long bp, char *log_lvl) | |
160 | { | |
ca0a8164 | 161 | printk("%sCall Trace:\n", log_lvl); |
2bc5f927 | 162 | dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl); |
2bc5f927 AH |
163 | } |
164 | ||
165 | void show_trace(struct task_struct *task, struct pt_regs *regs, | |
166 | unsigned long *stack, unsigned long bp) | |
167 | { | |
168 | show_trace_log_lvl(task, regs, stack, bp, ""); | |
169 | } | |
170 | ||
171 | static void | |
172 | show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, | |
8a541665 | 173 | unsigned long *sp, unsigned long bp, char *log_lvl) |
2bc5f927 AH |
174 | { |
175 | unsigned long *stack; | |
176 | int i; | |
177 | ||
178 | if (sp == NULL) { | |
179 | if (task) | |
180 | sp = (unsigned long *)task->thread.sp; | |
181 | else | |
182 | sp = (unsigned long *)&sp; | |
183 | } | |
184 | ||
185 | stack = sp; | |
186 | for (i = 0; i < kstack_depth_to_print; i++) { | |
187 | if (kstack_end(stack)) | |
188 | break; | |
8a541665 | 189 | if (i && ((i % STACKSLOTS_PER_LINE) == 0)) |
ca0a8164 AH |
190 | printk("\n%s", log_lvl); |
191 | printk(" %08lx", *stack++); | |
192 | touch_nmi_watchdog(); | |
2bc5f927 | 193 | } |
ca0a8164 | 194 | printk("\n"); |
2bc5f927 AH |
195 | show_trace_log_lvl(task, regs, sp, bp, log_lvl); |
196 | } | |
197 | ||
198 | void show_stack(struct task_struct *task, unsigned long *sp) | |
199 | { | |
2bc5f927 AH |
200 | show_stack_log_lvl(task, NULL, sp, 0, ""); |
201 | } | |
202 | ||
203 | /* | |
204 | * The architecture-independent dump_stack generator | |
205 | */ | |
206 | void dump_stack(void) | |
207 | { | |
208 | unsigned long bp = 0; | |
209 | unsigned long stack; | |
210 | ||
211 | #ifdef CONFIG_FRAME_POINTER | |
212 | if (!bp) | |
8a541665 | 213 | get_bp(bp); |
2bc5f927 AH |
214 | #endif |
215 | ||
216 | printk("Pid: %d, comm: %.20s %s %s %.*s\n", | |
217 | current->pid, current->comm, print_tainted(), | |
218 | init_utsname()->release, | |
219 | (int)strcspn(init_utsname()->version, " "), | |
220 | init_utsname()->version); | |
8a541665 | 221 | show_trace(NULL, NULL, &stack, bp); |
2bc5f927 AH |
222 | } |
223 | ||
224 | EXPORT_SYMBOL(dump_stack); | |
225 | ||
226 | void show_registers(struct pt_regs *regs) | |
227 | { | |
228 | int i; | |
229 | ||
230 | print_modules(); | |
231 | __show_regs(regs, 0); | |
232 | ||
ca0a8164 | 233 | printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n", |
2bc5f927 AH |
234 | TASK_COMM_LEN, current->comm, task_pid_nr(current), |
235 | current_thread_info(), current, task_thread_info(current)); | |
236 | /* | |
237 | * When in-kernel, we also print out the stack and code at the | |
238 | * time of the fault.. | |
239 | */ | |
240 | if (!user_mode_vm(regs)) { | |
241 | unsigned int code_prologue = code_bytes * 43 / 64; | |
242 | unsigned int code_len = code_bytes; | |
243 | unsigned char c; | |
244 | u8 *ip; | |
245 | ||
ca0a8164 AH |
246 | printk(KERN_EMERG "Stack:\n"); |
247 | show_stack_log_lvl(NULL, regs, ®s->sp, | |
248 | 0, KERN_EMERG); | |
2bc5f927 AH |
249 | |
250 | printk(KERN_EMERG "Code: "); | |
251 | ||
252 | ip = (u8 *)regs->ip - code_prologue; | |
253 | if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) { | |
8a541665 | 254 | /* try starting at IP */ |
2bc5f927 AH |
255 | ip = (u8 *)regs->ip; |
256 | code_len = code_len - code_prologue + 1; | |
257 | } | |
258 | for (i = 0; i < code_len; i++, ip++) { | |
259 | if (ip < (u8 *)PAGE_OFFSET || | |
260 | probe_kernel_address(ip, c)) { | |
261 | printk(" Bad EIP value."); | |
262 | break; | |
263 | } | |
264 | if (ip == (u8 *)regs->ip) | |
265 | printk("<%02x> ", c); | |
266 | else | |
267 | printk("%02x ", c); | |
268 | } | |
269 | } | |
270 | printk("\n"); | |
271 | } | |
272 | ||
273 | int is_valid_bugaddr(unsigned long ip) | |
274 | { | |
275 | unsigned short ud2; | |
276 | ||
277 | if (ip < PAGE_OFFSET) | |
278 | return 0; | |
279 | if (probe_kernel_address((unsigned short *)ip, ud2)) | |
280 | return 0; | |
281 | ||
282 | return ud2 == 0x0b0f; | |
283 | } | |
284 | ||
285 | static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
286 | static int die_owner = -1; | |
287 | static unsigned int die_nest_count; | |
288 | ||
289 | unsigned __kprobes long oops_begin(void) | |
290 | { | |
291 | unsigned long flags; | |
292 | ||
293 | oops_enter(); | |
294 | ||
295 | if (die_owner != raw_smp_processor_id()) { | |
296 | console_verbose(); | |
297 | raw_local_irq_save(flags); | |
298 | __raw_spin_lock(&die_lock); | |
299 | die_owner = smp_processor_id(); | |
300 | die_nest_count = 0; | |
301 | bust_spinlocks(1); | |
302 | } else { | |
303 | raw_local_irq_save(flags); | |
304 | } | |
305 | die_nest_count++; | |
306 | return flags; | |
307 | } | |
308 | ||
309 | void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr) | |
310 | { | |
311 | bust_spinlocks(0); | |
312 | die_owner = -1; | |
313 | add_taint(TAINT_DIE); | |
314 | __raw_spin_unlock(&die_lock); | |
315 | raw_local_irq_restore(flags); | |
316 | ||
317 | if (!regs) | |
318 | return; | |
319 | ||
320 | if (kexec_should_crash(current)) | |
321 | crash_kexec(regs); | |
2bc5f927 AH |
322 | if (in_interrupt()) |
323 | panic("Fatal exception in interrupt"); | |
2bc5f927 AH |
324 | if (panic_on_oops) |
325 | panic("Fatal exception"); | |
2bc5f927 AH |
326 | oops_exit(); |
327 | do_exit(signr); | |
328 | } | |
329 | ||
330 | int __kprobes __die(const char *str, struct pt_regs *regs, long err) | |
331 | { | |
332 | unsigned short ss; | |
333 | unsigned long sp; | |
334 | ||
335 | printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter); | |
336 | #ifdef CONFIG_PREEMPT | |
337 | printk("PREEMPT "); | |
338 | #endif | |
339 | #ifdef CONFIG_SMP | |
340 | printk("SMP "); | |
341 | #endif | |
342 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
343 | printk("DEBUG_PAGEALLOC"); | |
344 | #endif | |
345 | printk("\n"); | |
346 | if (notify_die(DIE_OOPS, str, regs, err, | |
347 | current->thread.trap_no, SIGSEGV) == NOTIFY_STOP) | |
348 | return 1; | |
349 | ||
350 | show_registers(regs); | |
351 | /* Executive summary in case the oops scrolled away */ | |
352 | sp = (unsigned long) (®s->sp); | |
353 | savesegment(ss, ss); | |
354 | if (user_mode(regs)) { | |
355 | sp = regs->sp; | |
356 | ss = regs->ss & 0xffff; | |
357 | } | |
358 | printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip); | |
359 | print_symbol("%s", regs->ip); | |
360 | printk(" SS:ESP %04x:%08lx\n", ss, sp); | |
361 | return 0; | |
362 | } | |
363 | ||
364 | /* | |
365 | * This is gone through when something in the kernel has done something bad | |
366 | * and is about to be terminated: | |
367 | */ | |
368 | void die(const char *str, struct pt_regs *regs, long err) | |
369 | { | |
370 | unsigned long flags = oops_begin(); | |
371 | ||
372 | if (die_nest_count < 3) { | |
373 | report_bug(regs->ip, regs); | |
374 | ||
375 | if (__die(str, regs, err)) | |
376 | regs = NULL; | |
377 | } else { | |
378 | printk(KERN_EMERG "Recursive die() failure, output suppressed\n"); | |
379 | } | |
380 | ||
381 | oops_end(flags, regs, SIGSEGV); | |
382 | } | |
383 | ||
dd6e4eba AH |
384 | static DEFINE_SPINLOCK(nmi_print_lock); |
385 | ||
386 | void notrace __kprobes | |
387 | die_nmi(char *str, struct pt_regs *regs, int do_panic) | |
388 | { | |
389 | if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP) | |
390 | return; | |
391 | ||
392 | spin_lock(&nmi_print_lock); | |
393 | /* | |
394 | * We are in trouble anyway, lets at least try | |
395 | * to get a message out: | |
396 | */ | |
397 | bust_spinlocks(1); | |
398 | printk(KERN_EMERG "%s", str); | |
399 | printk(" on CPU%d, ip %08lx, registers:\n", | |
400 | smp_processor_id(), regs->ip); | |
401 | show_registers(regs); | |
402 | if (do_panic) | |
403 | panic("Non maskable interrupt"); | |
404 | console_silent(); | |
405 | spin_unlock(&nmi_print_lock); | |
406 | bust_spinlocks(0); | |
407 | ||
408 | /* | |
409 | * If we are in kernel we are probably nested up pretty bad | |
410 | * and might aswell get out now while we still can: | |
411 | */ | |
412 | if (!user_mode_vm(regs)) { | |
413 | current->thread.trap_no = 2; | |
414 | crash_kexec(regs); | |
415 | } | |
416 | ||
417 | do_exit(SIGSEGV); | |
418 | } | |
419 | ||
802a67de AH |
420 | static int __init oops_setup(char *s) |
421 | { | |
422 | if (!s) | |
423 | return -EINVAL; | |
424 | if (!strcmp(s, "panic")) | |
425 | panic_on_oops = 1; | |
426 | return 0; | |
427 | } | |
428 | early_param("oops", oops_setup); | |
429 | ||
2bc5f927 AH |
430 | static int __init kstack_setup(char *s) |
431 | { | |
802a67de AH |
432 | if (!s) |
433 | return -EINVAL; | |
2bc5f927 | 434 | kstack_depth_to_print = simple_strtoul(s, NULL, 0); |
802a67de | 435 | return 0; |
2bc5f927 | 436 | } |
802a67de | 437 | early_param("kstack", kstack_setup); |
2bc5f927 AH |
438 | |
439 | static int __init code_bytes_setup(char *s) | |
440 | { | |
441 | code_bytes = simple_strtoul(s, NULL, 0); | |
442 | if (code_bytes > 8192) | |
443 | code_bytes = 8192; | |
444 | ||
445 | return 1; | |
446 | } | |
447 | __setup("code_bytes=", code_bytes_setup); |