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> | |
ae87221d | 16 | #include <linux/sysfs.h> |
2bc5f927 AH |
17 | |
18 | #include <asm/stacktrace.h> | |
19 | ||
8a541665 AH |
20 | #define STACKSLOTS_PER_LINE 8 |
21 | #define get_bp(bp) asm("movl %%ebp, %0" : "=r" (bp) :) | |
22 | ||
2bc5f927 | 23 | int panic_on_unrecovered_nmi; |
8a541665 | 24 | int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; |
2bc5f927 AH |
25 | static unsigned int code_bytes = 64; |
26 | static int die_counter; | |
27 | ||
28 | void printk_address(unsigned long address, int reliable) | |
29 | { | |
16182790 AH |
30 | printk(" [<%p>] %s%pS\n", (void *) address, |
31 | reliable ? "" : "? ", (void *) address); | |
2bc5f927 AH |
32 | } |
33 | ||
34 | static inline int valid_stack_ptr(struct thread_info *tinfo, | |
3a18512d | 35 | void *p, unsigned int size, void *end) |
2bc5f927 AH |
36 | { |
37 | void *t = tinfo; | |
3a18512d AH |
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; | |
2bc5f927 AH |
45 | } |
46 | ||
47 | /* The form of the top of the frame on the stack */ | |
48 | struct stack_frame { | |
49 | struct stack_frame *next_frame; | |
50 | unsigned long return_address; | |
51 | }; | |
52 | ||
53 | static inline unsigned long | |
54 | print_context_stack(struct thread_info *tinfo, | |
55 | unsigned long *stack, unsigned long bp, | |
3a18512d AH |
56 | const struct stacktrace_ops *ops, void *data, |
57 | unsigned long *end) | |
2bc5f927 AH |
58 | { |
59 | struct stack_frame *frame = (struct stack_frame *)bp; | |
60 | ||
3a18512d | 61 | while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) { |
2bc5f927 AH |
62 | unsigned long addr; |
63 | ||
64 | addr = *stack; | |
65 | if (__kernel_text_address(addr)) { | |
3a18512d | 66 | if ((unsigned long) stack == bp + sizeof(long)) { |
2bc5f927 AH |
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 | ||
79 | void 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; | |
8a541665 | 89 | if (task && task != current) |
2bc5f927 AH |
90 | stack = (unsigned long *)task->thread.sp; |
91 | } | |
92 | ||
93 | #ifdef CONFIG_FRAME_POINTER | |
94 | if (!bp) { | |
95 | if (task == current) { | |
96 | /* Grab bp right from our regs */ | |
8a541665 | 97 | get_bp(bp); |
2bc5f927 AH |
98 | } else { |
99 | /* bp is the last reg pushed by switch_to */ | |
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))); | |
3a18512d | 110 | bp = print_context_stack(context, stack, bp, ops, data, NULL); |
2ac53721 | 111 | |
2bc5f927 AH |
112 | stack = (unsigned long *)context->previous_esp; |
113 | if (!stack) | |
114 | break; | |
2ac53721 AH |
115 | if (ops->stack(data, "IRQ") < 0) |
116 | break; | |
2bc5f927 AH |
117 | touch_nmi_watchdog(); |
118 | } | |
119 | } | |
120 | EXPORT_SYMBOL(dump_trace); | |
121 | ||
122 | static void | |
123 | print_trace_warning_symbol(void *data, char *msg, unsigned long symbol) | |
124 | { | |
125 | printk(data); | |
126 | print_symbol(msg, symbol); | |
127 | printk("\n"); | |
128 | } | |
129 | ||
130 | static void print_trace_warning(void *data, char *msg) | |
131 | { | |
132 | printk("%s%s\n", (char *)data, msg); | |
133 | } | |
134 | ||
135 | static int print_trace_stack(void *data, char *name) | |
136 | { | |
2ac53721 | 137 | printk("%s <%s> ", (char *)data, name); |
2bc5f927 AH |
138 | return 0; |
139 | } | |
140 | ||
141 | /* | |
142 | * Print one address/symbol entries per line. | |
143 | */ | |
144 | static void print_trace_address(void *data, unsigned long addr, int reliable) | |
145 | { | |
2bc5f927 | 146 | touch_nmi_watchdog(); |
2ac53721 AH |
147 | printk(data); |
148 | printk_address(addr, reliable); | |
2bc5f927 AH |
149 | } |
150 | ||
151 | static 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 | ||
158 | static void | |
159 | show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, | |
160 | unsigned long *stack, unsigned long bp, char *log_lvl) | |
161 | { | |
ca0a8164 | 162 | printk("%sCall Trace:\n", log_lvl); |
2bc5f927 | 163 | dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl); |
2bc5f927 AH |
164 | } |
165 | ||
166 | void 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 | ||
172 | static void | |
173 | show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, | |
8a541665 | 174 | unsigned long *sp, unsigned long bp, char *log_lvl) |
2bc5f927 AH |
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; | |
8a541665 | 190 | if (i && ((i % STACKSLOTS_PER_LINE) == 0)) |
ca0a8164 AH |
191 | printk("\n%s", log_lvl); |
192 | printk(" %08lx", *stack++); | |
193 | touch_nmi_watchdog(); | |
2bc5f927 | 194 | } |
ca0a8164 | 195 | printk("\n"); |
2bc5f927 AH |
196 | show_trace_log_lvl(task, regs, sp, bp, log_lvl); |
197 | } | |
198 | ||
199 | void show_stack(struct task_struct *task, unsigned long *sp) | |
200 | { | |
2bc5f927 AH |
201 | show_stack_log_lvl(task, NULL, sp, 0, ""); |
202 | } | |
203 | ||
204 | /* | |
205 | * The architecture-independent dump_stack generator | |
206 | */ | |
207 | void dump_stack(void) | |
208 | { | |
209 | unsigned long bp = 0; | |
210 | unsigned long stack; | |
211 | ||
212 | #ifdef CONFIG_FRAME_POINTER | |
213 | if (!bp) | |
8a541665 | 214 | get_bp(bp); |
2bc5f927 AH |
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); | |
8a541665 | 222 | show_trace(NULL, NULL, &stack, bp); |
2bc5f927 AH |
223 | } |
224 | ||
225 | EXPORT_SYMBOL(dump_stack); | |
226 | ||
227 | void show_registers(struct pt_regs *regs) | |
228 | { | |
229 | int i; | |
230 | ||
231 | print_modules(); | |
232 | __show_regs(regs, 0); | |
233 | ||
ca0a8164 | 234 | printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n", |
2bc5f927 AH |
235 | TASK_COMM_LEN, current->comm, task_pid_nr(current), |
236 | current_thread_info(), current, task_thread_info(current)); | |
237 | /* | |
238 | * When in-kernel, we also print out the stack and code at the | |
239 | * time of the fault.. | |
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 | ||
ca0a8164 AH |
247 | printk(KERN_EMERG "Stack:\n"); |
248 | show_stack_log_lvl(NULL, regs, ®s->sp, | |
249 | 0, KERN_EMERG); | |
2bc5f927 AH |
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)) { | |
8a541665 | 255 | /* try starting at IP */ |
2bc5f927 AH |
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 | ||
274 | int 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 | ||
286 | static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
287 | static int die_owner = -1; | |
288 | static unsigned int die_nest_count; | |
289 | ||
290 | unsigned __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 | ||
310 | void __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); | |
2bc5f927 AH |
323 | if (in_interrupt()) |
324 | panic("Fatal exception in interrupt"); | |
2bc5f927 AH |
325 | if (panic_on_oops) |
326 | panic("Fatal exception"); | |
2bc5f927 AH |
327 | oops_exit(); |
328 | do_exit(signr); | |
329 | } | |
330 | ||
331 | int __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"); | |
ae87221d | 347 | sysfs_printk_last_file(); |
2bc5f927 AH |
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 | /* Executive summary in case the oops scrolled away */ | |
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 | * This is gone through when something in the kernel has done something bad | |
368 | * and is about to be terminated: | |
369 | */ | |
370 | void 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 | ||
dd6e4eba AH |
386 | static DEFINE_SPINLOCK(nmi_print_lock); |
387 | ||
388 | void notrace __kprobes | |
389 | die_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 | * We are in trouble anyway, lets at least try | |
397 | * to get a message out: | |
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); | |
dd6e4eba AH |
408 | |
409 | /* | |
410 | * If we are in kernel we are probably nested up pretty bad | |
411 | * and might aswell get out now while we still can: | |
412 | */ | |
413 | if (!user_mode_vm(regs)) { | |
414 | current->thread.trap_no = 2; | |
415 | crash_kexec(regs); | |
416 | } | |
417 | ||
cf52ebed | 418 | bust_spinlocks(0); |
dd6e4eba AH |
419 | do_exit(SIGSEGV); |
420 | } | |
421 | ||
802a67de AH |
422 | static 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 | } | |
430 | early_param("oops", oops_setup); | |
431 | ||
2bc5f927 AH |
432 | static int __init kstack_setup(char *s) |
433 | { | |
802a67de AH |
434 | if (!s) |
435 | return -EINVAL; | |
2bc5f927 | 436 | kstack_depth_to_print = simple_strtoul(s, NULL, 0); |
802a67de | 437 | return 0; |
2bc5f927 | 438 | } |
802a67de | 439 | early_param("kstack", kstack_setup); |
2bc5f927 AH |
440 | |
441 | static 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); |