Commit | Line | Data |
---|---|---|
878719e8 NH |
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> | |
712406a6 | 13 | #include <linux/ftrace.h> |
878719e8 NH |
14 | #include <linux/kexec.h> |
15 | #include <linux/bug.h> | |
16 | #include <linux/nmi.h> | |
17 | #include <linux/sysfs.h> | |
18 | ||
19 | #include <asm/stacktrace.h> | |
20 | ||
878719e8 NH |
21 | |
22 | int panic_on_unrecovered_nmi; | |
5211a242 | 23 | int panic_on_io_nmi; |
878719e8 NH |
24 | unsigned int code_bytes = 64; |
25 | int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; | |
26 | static int die_counter; | |
27 | ||
1fc7f61c AS |
28 | static void printk_stack_address(unsigned long address, int reliable, |
29 | void *data) | |
878719e8 | 30 | { |
1fc7f61c AS |
31 | printk("%s [<%p>] %s%pB\n", |
32 | (char *)data, (void *)address, reliable ? "" : "? ", | |
33 | (void *)address); | |
878719e8 NH |
34 | } |
35 | ||
5f01c988 JS |
36 | void printk_address(unsigned long address) |
37 | { | |
38 | pr_cont(" [<%p>] %pS\n", (void *)address, (void *)address); | |
39 | } | |
40 | ||
7ee991fb SR |
41 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
42 | static void | |
43 | print_ftrace_graph_addr(unsigned long addr, void *data, | |
44 | const struct stacktrace_ops *ops, | |
45 | struct thread_info *tinfo, int *graph) | |
46 | { | |
65c0ff40 | 47 | struct task_struct *task; |
7ee991fb | 48 | unsigned long ret_addr; |
65c0ff40 | 49 | int index; |
7ee991fb SR |
50 | |
51 | if (addr != (unsigned long)return_to_handler) | |
52 | return; | |
53 | ||
65c0ff40 HD |
54 | task = tinfo->task; |
55 | index = task->curr_ret_stack; | |
56 | ||
7ee991fb SR |
57 | if (!task->ret_stack || index < *graph) |
58 | return; | |
59 | ||
60 | index -= *graph; | |
61 | ret_addr = task->ret_stack[index].ret; | |
62 | ||
63 | ops->address(data, ret_addr, 1); | |
64 | ||
65 | (*graph)++; | |
66 | } | |
67 | #else | |
68 | static inline void | |
69 | print_ftrace_graph_addr(unsigned long addr, void *data, | |
70 | const struct stacktrace_ops *ops, | |
71 | struct thread_info *tinfo, int *graph) | |
72 | { } | |
73 | #endif | |
74 | ||
878719e8 NH |
75 | /* |
76 | * x86-64 can have up to three kernel stacks: | |
77 | * process stack | |
78 | * interrupt stack | |
79 | * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack | |
80 | */ | |
81 | ||
82 | static inline int valid_stack_ptr(struct thread_info *tinfo, | |
83 | void *p, unsigned int size, void *end) | |
84 | { | |
85 | void *t = tinfo; | |
86 | if (end) { | |
87 | if (p < end && p >= (end-THREAD_SIZE)) | |
88 | return 1; | |
89 | else | |
90 | return 0; | |
91 | } | |
92 | return p > t && p < t + THREAD_SIZE - size; | |
93 | } | |
94 | ||
95 | unsigned long | |
96 | print_context_stack(struct thread_info *tinfo, | |
97 | unsigned long *stack, unsigned long bp, | |
98 | const struct stacktrace_ops *ops, void *data, | |
7ee991fb | 99 | unsigned long *end, int *graph) |
878719e8 NH |
100 | { |
101 | struct stack_frame *frame = (struct stack_frame *)bp; | |
102 | ||
103 | while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) { | |
104 | unsigned long addr; | |
105 | ||
106 | addr = *stack; | |
107 | if (__kernel_text_address(addr)) { | |
108 | if ((unsigned long) stack == bp + sizeof(long)) { | |
109 | ops->address(data, addr, 1); | |
110 | frame = frame->next_frame; | |
111 | bp = (unsigned long) frame; | |
112 | } else { | |
2c344e9d | 113 | ops->address(data, addr, 0); |
878719e8 | 114 | } |
7ee991fb | 115 | print_ftrace_graph_addr(addr, data, ops, tinfo, graph); |
878719e8 NH |
116 | } |
117 | stack++; | |
118 | } | |
119 | return bp; | |
120 | } | |
06d65bda FW |
121 | EXPORT_SYMBOL_GPL(print_context_stack); |
122 | ||
123 | unsigned long | |
124 | print_context_stack_bp(struct thread_info *tinfo, | |
125 | unsigned long *stack, unsigned long bp, | |
126 | const struct stacktrace_ops *ops, void *data, | |
127 | unsigned long *end, int *graph) | |
128 | { | |
129 | struct stack_frame *frame = (struct stack_frame *)bp; | |
130 | unsigned long *ret_addr = &frame->return_address; | |
131 | ||
132 | while (valid_stack_ptr(tinfo, ret_addr, sizeof(*ret_addr), end)) { | |
133 | unsigned long addr = *ret_addr; | |
134 | ||
c2c5d45d FW |
135 | if (!__kernel_text_address(addr)) |
136 | break; | |
137 | ||
568b329a AS |
138 | if (ops->address(data, addr, 1)) |
139 | break; | |
c2c5d45d FW |
140 | frame = frame->next_frame; |
141 | ret_addr = &frame->return_address; | |
142 | print_ftrace_graph_addr(addr, data, ops, tinfo, graph); | |
06d65bda | 143 | } |
c2c5d45d | 144 | |
06d65bda FW |
145 | return (unsigned long)frame; |
146 | } | |
147 | EXPORT_SYMBOL_GPL(print_context_stack_bp); | |
878719e8 | 148 | |
878719e8 NH |
149 | static int print_trace_stack(void *data, char *name) |
150 | { | |
151 | printk("%s <%s> ", (char *)data, name); | |
152 | return 0; | |
153 | } | |
154 | ||
155 | /* | |
156 | * Print one address/symbol entries per line. | |
157 | */ | |
568b329a | 158 | static int print_trace_address(void *data, unsigned long addr, int reliable) |
878719e8 NH |
159 | { |
160 | touch_nmi_watchdog(); | |
1fc7f61c | 161 | printk_stack_address(addr, reliable, data); |
568b329a | 162 | return 0; |
878719e8 NH |
163 | } |
164 | ||
165 | static const struct stacktrace_ops print_trace_ops = { | |
06d65bda FW |
166 | .stack = print_trace_stack, |
167 | .address = print_trace_address, | |
61c1917f | 168 | .walk_stack = print_context_stack, |
878719e8 NH |
169 | }; |
170 | ||
171 | void | |
172 | show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, | |
e8e999cf | 173 | unsigned long *stack, unsigned long bp, char *log_lvl) |
878719e8 NH |
174 | { |
175 | printk("%sCall Trace:\n", log_lvl); | |
e8e999cf | 176 | dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl); |
878719e8 NH |
177 | } |
178 | ||
179 | void show_trace(struct task_struct *task, struct pt_regs *regs, | |
e8e999cf | 180 | unsigned long *stack, unsigned long bp) |
878719e8 | 181 | { |
e8e999cf | 182 | show_trace_log_lvl(task, regs, stack, bp, ""); |
878719e8 NH |
183 | } |
184 | ||
185 | void show_stack(struct task_struct *task, unsigned long *sp) | |
186 | { | |
a77f2a4e TH |
187 | unsigned long bp = 0; |
188 | unsigned long stack; | |
189 | ||
190 | /* | |
191 | * Stack frames below this one aren't interesting. Don't show them | |
192 | * if we're printing for %current. | |
193 | */ | |
194 | if (!sp && (!task || task == current)) { | |
195 | sp = &stack; | |
196 | bp = stack_frame(current, NULL); | |
197 | } | |
198 | ||
199 | show_stack_log_lvl(task, NULL, sp, bp, ""); | |
878719e8 NH |
200 | } |
201 | ||
edc35bd7 | 202 | static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
878719e8 NH |
203 | static int die_owner = -1; |
204 | static unsigned int die_nest_count; | |
205 | ||
9326638c | 206 | unsigned long oops_begin(void) |
878719e8 NH |
207 | { |
208 | int cpu; | |
209 | unsigned long flags; | |
210 | ||
211 | oops_enter(); | |
212 | ||
213 | /* racy, but better than risking deadlock. */ | |
214 | raw_local_irq_save(flags); | |
215 | cpu = smp_processor_id(); | |
0199c4e6 | 216 | if (!arch_spin_trylock(&die_lock)) { |
878719e8 NH |
217 | if (cpu == die_owner) |
218 | /* nested oops. should stop eventually */; | |
219 | else | |
0199c4e6 | 220 | arch_spin_lock(&die_lock); |
878719e8 NH |
221 | } |
222 | die_nest_count++; | |
223 | die_owner = cpu; | |
224 | console_verbose(); | |
225 | bust_spinlocks(1); | |
226 | return flags; | |
227 | } | |
81e88fdc | 228 | EXPORT_SYMBOL_GPL(oops_begin); |
9326638c | 229 | NOKPROBE_SYMBOL(oops_begin); |
878719e8 | 230 | |
9326638c | 231 | void oops_end(unsigned long flags, struct pt_regs *regs, int signr) |
878719e8 NH |
232 | { |
233 | if (regs && kexec_should_crash(current)) | |
234 | crash_kexec(regs); | |
235 | ||
236 | bust_spinlocks(0); | |
237 | die_owner = -1; | |
373d4d09 | 238 | add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); |
878719e8 NH |
239 | die_nest_count--; |
240 | if (!die_nest_count) | |
241 | /* Nest count reaches zero, release the lock. */ | |
0199c4e6 | 242 | arch_spin_unlock(&die_lock); |
878719e8 NH |
243 | raw_local_irq_restore(flags); |
244 | oops_exit(); | |
245 | ||
246 | if (!signr) | |
247 | return; | |
248 | if (in_interrupt()) | |
249 | panic("Fatal exception in interrupt"); | |
250 | if (panic_on_oops) | |
251 | panic("Fatal exception"); | |
252 | do_exit(signr); | |
253 | } | |
9326638c | 254 | NOKPROBE_SYMBOL(oops_end); |
878719e8 | 255 | |
9326638c | 256 | int __die(const char *str, struct pt_regs *regs, long err) |
878719e8 NH |
257 | { |
258 | #ifdef CONFIG_X86_32 | |
259 | unsigned short ss; | |
260 | unsigned long sp; | |
261 | #endif | |
b0f4c4b3 PB |
262 | printk(KERN_DEFAULT |
263 | "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter); | |
878719e8 NH |
264 | #ifdef CONFIG_PREEMPT |
265 | printk("PREEMPT "); | |
266 | #endif | |
267 | #ifdef CONFIG_SMP | |
268 | printk("SMP "); | |
269 | #endif | |
288cf3c6 CB |
270 | if (debug_pagealloc_enabled()) |
271 | printk("DEBUG_PAGEALLOC "); | |
ef7f0d6a AR |
272 | #ifdef CONFIG_KASAN |
273 | printk("KASAN"); | |
878719e8 NH |
274 | #endif |
275 | printk("\n"); | |
878719e8 | 276 | if (notify_die(DIE_OOPS, str, regs, err, |
51e7dc70 | 277 | current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP) |
878719e8 NH |
278 | return 1; |
279 | ||
0fa0e2f0 | 280 | print_modules(); |
57da8b96 | 281 | show_regs(regs); |
878719e8 | 282 | #ifdef CONFIG_X86_32 |
f39b6f0e | 283 | if (user_mode(regs)) { |
878719e8 NH |
284 | sp = regs->sp; |
285 | ss = regs->ss & 0xffff; | |
a343c75d PA |
286 | } else { |
287 | sp = kernel_stack_pointer(regs); | |
288 | savesegment(ss, ss); | |
878719e8 NH |
289 | } |
290 | printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip); | |
291 | print_symbol("%s", regs->ip); | |
292 | printk(" SS:ESP %04x:%08lx\n", ss, sp); | |
293 | #else | |
294 | /* Executive summary in case the oops scrolled away */ | |
295 | printk(KERN_ALERT "RIP "); | |
5f01c988 | 296 | printk_address(regs->ip); |
878719e8 NH |
297 | printk(" RSP <%016lx>\n", regs->sp); |
298 | #endif | |
299 | return 0; | |
300 | } | |
9326638c | 301 | NOKPROBE_SYMBOL(__die); |
878719e8 NH |
302 | |
303 | /* | |
304 | * This is gone through when something in the kernel has done something bad | |
305 | * and is about to be terminated: | |
306 | */ | |
307 | void die(const char *str, struct pt_regs *regs, long err) | |
308 | { | |
309 | unsigned long flags = oops_begin(); | |
310 | int sig = SIGSEGV; | |
311 | ||
f39b6f0e | 312 | if (!user_mode(regs)) |
878719e8 NH |
313 | report_bug(regs->ip, regs); |
314 | ||
315 | if (__die(str, regs, err)) | |
316 | sig = 0; | |
317 | oops_end(flags, regs, sig); | |
318 | } | |
319 | ||
878719e8 NH |
320 | static int __init kstack_setup(char *s) |
321 | { | |
363f7ce3 SK |
322 | ssize_t ret; |
323 | unsigned long val; | |
324 | ||
878719e8 NH |
325 | if (!s) |
326 | return -EINVAL; | |
363f7ce3 SK |
327 | |
328 | ret = kstrtoul(s, 0, &val); | |
329 | if (ret) | |
330 | return ret; | |
331 | kstack_depth_to_print = val; | |
878719e8 NH |
332 | return 0; |
333 | } | |
334 | early_param("kstack", kstack_setup); | |
335 | ||
336 | static int __init code_bytes_setup(char *s) | |
337 | { | |
363f7ce3 SK |
338 | ssize_t ret; |
339 | unsigned long val; | |
340 | ||
341 | if (!s) | |
342 | return -EINVAL; | |
343 | ||
344 | ret = kstrtoul(s, 0, &val); | |
345 | if (ret) | |
346 | return ret; | |
347 | ||
348 | code_bytes = val; | |
878719e8 NH |
349 | if (code_bytes > 8192) |
350 | code_bytes = 8192; | |
351 | ||
352 | return 1; | |
353 | } | |
354 | __setup("code_bytes=", code_bytes_setup); |