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11#include <linux/debug_locks.h>
12#include <linux/interrupt.h>
13#include <linux/kallsyms.h>
14#include <linux/notifier.h>
15#include <linux/module.h>
16#include <linux/random.h>
17#include <linux/reboot.h>
18#include <linux/delay.h>
19#include <linux/kexec.h>
20#include <linux/sched.h>
21#include <linux/sysrq.h>
22#include <linux/init.h>
23#include <linux/nmi.h>
24#include <linux/dmi.h>
25
26int panic_on_oops;
27static unsigned long tainted_mask;
28static int pause_on_oops;
29static int pause_on_oops_flag;
30static DEFINE_SPINLOCK(pause_on_oops_lock);
31
32int panic_timeout;
33
34ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
35
36EXPORT_SYMBOL(panic_notifier_list);
37
38static long no_blink(long time)
39{
40 return 0;
41}
42
43
44long (*panic_blink)(long time);
45EXPORT_SYMBOL(panic_blink);
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54
55NORET_TYPE void panic(const char * fmt, ...)
56{
57 static char buf[1024];
58 va_list args;
59 long i;
60
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65
66 preempt_disable();
67
68 bust_spinlocks(1);
69 va_start(args, fmt);
70 vsnprintf(buf, sizeof(buf), fmt, args);
71 va_end(args);
72 printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
73#ifdef CONFIG_DEBUG_BUGVERBOSE
74 dump_stack();
75#endif
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81
82 crash_kexec(NULL);
83
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88
89 smp_send_stop();
90
91 atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
92
93 if (!panic_blink)
94 panic_blink = no_blink;
95
96 if (panic_timeout > 0) {
97
98
99
100
101 printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout);
102
103 for (i = 0; i < panic_timeout*1000; ) {
104 touch_nmi_watchdog();
105 i += panic_blink(i);
106 mdelay(1);
107 i++;
108 }
109
110
111
112
113
114 emergency_restart();
115 }
116#ifdef __sparc__
117 {
118 extern int stop_a_enabled;
119
120 stop_a_enabled = 1;
121 printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n");
122 }
123#endif
124#if defined(CONFIG_S390)
125 {
126 unsigned long caller;
127
128 caller = (unsigned long)__builtin_return_address(0);
129 disabled_wait(caller);
130 }
131#endif
132 local_irq_enable();
133 for (i = 0; ; ) {
134 touch_softlockup_watchdog();
135 i += panic_blink(i);
136 mdelay(1);
137 i++;
138 }
139 bust_spinlocks(0);
140}
141
142EXPORT_SYMBOL(panic);
143
144
145struct tnt {
146 u8 bit;
147 char true;
148 char false;
149};
150
151static const struct tnt tnts[] = {
152 { TAINT_PROPRIETARY_MODULE, 'P', 'G' },
153 { TAINT_FORCED_MODULE, 'F', ' ' },
154 { TAINT_UNSAFE_SMP, 'S', ' ' },
155 { TAINT_FORCED_RMMOD, 'R', ' ' },
156 { TAINT_MACHINE_CHECK, 'M', ' ' },
157 { TAINT_BAD_PAGE, 'B', ' ' },
158 { TAINT_USER, 'U', ' ' },
159 { TAINT_DIE, 'D', ' ' },
160 { TAINT_OVERRIDDEN_ACPI_TABLE, 'A', ' ' },
161 { TAINT_WARN, 'W', ' ' },
162 { TAINT_CRAP, 'C', ' ' },
163};
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181
182const char *print_tainted(void)
183{
184 static char buf[ARRAY_SIZE(tnts) + sizeof("Tainted: ") + 1];
185
186 if (tainted_mask) {
187 char *s;
188 int i;
189
190 s = buf + sprintf(buf, "Tainted: ");
191 for (i = 0; i < ARRAY_SIZE(tnts); i++) {
192 const struct tnt *t = &tnts[i];
193 *s++ = test_bit(t->bit, &tainted_mask) ?
194 t->true : t->false;
195 }
196 *s = 0;
197 } else
198 snprintf(buf, sizeof(buf), "Not tainted");
199
200 return buf;
201}
202
203int test_taint(unsigned flag)
204{
205 return test_bit(flag, &tainted_mask);
206}
207EXPORT_SYMBOL(test_taint);
208
209unsigned long get_taint(void)
210{
211 return tainted_mask;
212}
213
214void add_taint(unsigned flag)
215{
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222
223 if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off())
224 printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n");
225
226 set_bit(flag, &tainted_mask);
227}
228EXPORT_SYMBOL(add_taint);
229
230static void spin_msec(int msecs)
231{
232 int i;
233
234 for (i = 0; i < msecs; i++) {
235 touch_nmi_watchdog();
236 mdelay(1);
237 }
238}
239
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242
243
244static void do_oops_enter_exit(void)
245{
246 unsigned long flags;
247 static int spin_counter;
248
249 if (!pause_on_oops)
250 return;
251
252 spin_lock_irqsave(&pause_on_oops_lock, flags);
253 if (pause_on_oops_flag == 0) {
254
255 pause_on_oops_flag = 1;
256 } else {
257
258 if (!spin_counter) {
259
260 spin_counter = pause_on_oops;
261 do {
262 spin_unlock(&pause_on_oops_lock);
263 spin_msec(MSEC_PER_SEC);
264 spin_lock(&pause_on_oops_lock);
265 } while (--spin_counter);
266 pause_on_oops_flag = 0;
267 } else {
268
269 while (spin_counter) {
270 spin_unlock(&pause_on_oops_lock);
271 spin_msec(1);
272 spin_lock(&pause_on_oops_lock);
273 }
274 }
275 }
276 spin_unlock_irqrestore(&pause_on_oops_lock, flags);
277}
278
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282
283int oops_may_print(void)
284{
285 return pause_on_oops_flag == 0;
286}
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301
302void oops_enter(void)
303{
304
305 debug_locks_off();
306 do_oops_enter_exit();
307}
308
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311
312static u64 oops_id;
313
314static int init_oops_id(void)
315{
316 if (!oops_id)
317 get_random_bytes(&oops_id, sizeof(oops_id));
318 else
319 oops_id++;
320
321 return 0;
322}
323late_initcall(init_oops_id);
324
325static void print_oops_end_marker(void)
326{
327 init_oops_id();
328 printk(KERN_WARNING "---[ end trace %016llx ]---\n",
329 (unsigned long long)oops_id);
330}
331
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336void oops_exit(void)
337{
338 do_oops_enter_exit();
339 print_oops_end_marker();
340}
341
342#ifdef WANT_WARN_ON_SLOWPATH
343struct slowpath_args {
344 const char *fmt;
345 va_list args;
346};
347
348static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args)
349{
350 const char *board;
351
352 printk(KERN_WARNING "------------[ cut here ]------------\n");
353 printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);
354 board = dmi_get_system_info(DMI_PRODUCT_NAME);
355 if (board)
356 printk(KERN_WARNING "Hardware name: %s\n", board);
357
358 if (args)
359 vprintk(args->fmt, args->args);
360
361 print_modules();
362 dump_stack();
363 print_oops_end_marker();
364 add_taint(TAINT_WARN);
365}
366
367void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
368{
369 struct slowpath_args args;
370
371 args.fmt = fmt;
372 va_start(args.args, fmt);
373 warn_slowpath_common(file, line, __builtin_return_address(0), &args);
374 va_end(args.args);
375}
376EXPORT_SYMBOL(warn_slowpath_fmt);
377
378void warn_slowpath_null(const char *file, int line)
379{
380 warn_slowpath_common(file, line, __builtin_return_address(0), NULL);
381}
382EXPORT_SYMBOL(warn_slowpath_null);
383#endif
384
385#ifdef CONFIG_CC_STACKPROTECTOR
386
387
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389
390
391void __stack_chk_fail(void)
392{
393 panic("stack-protector: Kernel stack is corrupted in: %p\n",
394 __builtin_return_address(0));
395}
396EXPORT_SYMBOL(__stack_chk_fail);
397
398#endif
399
400core_param(panic, panic_timeout, int, 0644);
401core_param(pause_on_oops, pause_on_oops, int, 0644);
402