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11#include <linux/debug_locks.h>
12#include <linux/interrupt.h>
13#include <linux/kmsg_dump.h>
14#include <linux/kallsyms.h>
15#include <linux/notifier.h>
16#include <linux/module.h>
17#include <linux/random.h>
18#include <linux/reboot.h>
19#include <linux/delay.h>
20#include <linux/kexec.h>
21#include <linux/sched.h>
22#include <linux/sysrq.h>
23#include <linux/init.h>
24#include <linux/nmi.h>
25#include <linux/dmi.h>
26
27#define PANIC_TIMER_STEP 100
28#define PANIC_BLINK_SPD 18
29
30int panic_on_oops;
31static unsigned long tainted_mask;
32static int pause_on_oops;
33static int pause_on_oops_flag;
34static DEFINE_SPINLOCK(pause_on_oops_lock);
35
36int panic_timeout;
37EXPORT_SYMBOL_GPL(panic_timeout);
38
39ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
40
41EXPORT_SYMBOL(panic_notifier_list);
42
43static long no_blink(int state)
44{
45 return 0;
46}
47
48
49long (*panic_blink)(int state);
50EXPORT_SYMBOL(panic_blink);
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59
60NORET_TYPE void panic(const char * fmt, ...)
61{
62 static char buf[1024];
63 va_list args;
64 long i, i_next = 0;
65 int state = 0;
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70
71
72 preempt_disable();
73
74 console_verbose();
75 bust_spinlocks(1);
76 va_start(args, fmt);
77 vsnprintf(buf, sizeof(buf), fmt, args);
78 va_end(args);
79 printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
80#ifdef CONFIG_DEBUG_BUGVERBOSE
81 dump_stack();
82#endif
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88
89 crash_kexec(NULL);
90
91 kmsg_dump(KMSG_DUMP_PANIC);
92
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97
98 smp_send_stop();
99
100 atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
101
102 bust_spinlocks(0);
103
104 if (!panic_blink)
105 panic_blink = no_blink;
106
107 if (panic_timeout > 0) {
108
109
110
111
112 printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout);
113
114 for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) {
115 touch_nmi_watchdog();
116 if (i >= i_next) {
117 i += panic_blink(state ^= 1);
118 i_next = i + 3600 / PANIC_BLINK_SPD;
119 }
120 mdelay(PANIC_TIMER_STEP);
121 }
122
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126
127 emergency_restart();
128 }
129#ifdef __sparc__
130 {
131 extern int stop_a_enabled;
132
133 stop_a_enabled = 1;
134 printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n");
135 }
136#endif
137#if defined(CONFIG_S390)
138 {
139 unsigned long caller;
140
141 caller = (unsigned long)__builtin_return_address(0);
142 disabled_wait(caller);
143 }
144#endif
145 local_irq_enable();
146 for (i = 0; ; i += PANIC_TIMER_STEP) {
147 touch_softlockup_watchdog();
148 if (i >= i_next) {
149 i += panic_blink(state ^= 1);
150 i_next = i + 3600 / PANIC_BLINK_SPD;
151 }
152 mdelay(PANIC_TIMER_STEP);
153 }
154}
155
156EXPORT_SYMBOL(panic);
157
158
159struct tnt {
160 u8 bit;
161 char true;
162 char false;
163};
164
165static const struct tnt tnts[] = {
166 { TAINT_PROPRIETARY_MODULE, 'P', 'G' },
167 { TAINT_FORCED_MODULE, 'F', ' ' },
168 { TAINT_UNSAFE_SMP, 'S', ' ' },
169 { TAINT_FORCED_RMMOD, 'R', ' ' },
170 { TAINT_MACHINE_CHECK, 'M', ' ' },
171 { TAINT_BAD_PAGE, 'B', ' ' },
172 { TAINT_USER, 'U', ' ' },
173 { TAINT_DIE, 'D', ' ' },
174 { TAINT_OVERRIDDEN_ACPI_TABLE, 'A', ' ' },
175 { TAINT_WARN, 'W', ' ' },
176 { TAINT_CRAP, 'C', ' ' },
177 { TAINT_FIRMWARE_WORKAROUND, 'I', ' ' },
178};
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197
198const char *print_tainted(void)
199{
200 static char buf[ARRAY_SIZE(tnts) + sizeof("Tainted: ") + 1];
201
202 if (tainted_mask) {
203 char *s;
204 int i;
205
206 s = buf + sprintf(buf, "Tainted: ");
207 for (i = 0; i < ARRAY_SIZE(tnts); i++) {
208 const struct tnt *t = &tnts[i];
209 *s++ = test_bit(t->bit, &tainted_mask) ?
210 t->true : t->false;
211 }
212 *s = 0;
213 } else
214 snprintf(buf, sizeof(buf), "Not tainted");
215
216 return buf;
217}
218
219int test_taint(unsigned flag)
220{
221 return test_bit(flag, &tainted_mask);
222}
223EXPORT_SYMBOL(test_taint);
224
225unsigned long get_taint(void)
226{
227 return tainted_mask;
228}
229
230void add_taint(unsigned flag)
231{
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237
238
239 if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off())
240 printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n");
241
242 set_bit(flag, &tainted_mask);
243}
244EXPORT_SYMBOL(add_taint);
245
246static void spin_msec(int msecs)
247{
248 int i;
249
250 for (i = 0; i < msecs; i++) {
251 touch_nmi_watchdog();
252 mdelay(1);
253 }
254}
255
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258
259
260static void do_oops_enter_exit(void)
261{
262 unsigned long flags;
263 static int spin_counter;
264
265 if (!pause_on_oops)
266 return;
267
268 spin_lock_irqsave(&pause_on_oops_lock, flags);
269 if (pause_on_oops_flag == 0) {
270
271 pause_on_oops_flag = 1;
272 } else {
273
274 if (!spin_counter) {
275
276 spin_counter = pause_on_oops;
277 do {
278 spin_unlock(&pause_on_oops_lock);
279 spin_msec(MSEC_PER_SEC);
280 spin_lock(&pause_on_oops_lock);
281 } while (--spin_counter);
282 pause_on_oops_flag = 0;
283 } else {
284
285 while (spin_counter) {
286 spin_unlock(&pause_on_oops_lock);
287 spin_msec(1);
288 spin_lock(&pause_on_oops_lock);
289 }
290 }
291 }
292 spin_unlock_irqrestore(&pause_on_oops_lock, flags);
293}
294
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298
299int oops_may_print(void)
300{
301 return pause_on_oops_flag == 0;
302}
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318void oops_enter(void)
319{
320 tracing_off();
321
322 debug_locks_off();
323 do_oops_enter_exit();
324}
325
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328
329static u64 oops_id;
330
331static int init_oops_id(void)
332{
333 if (!oops_id)
334 get_random_bytes(&oops_id, sizeof(oops_id));
335 else
336 oops_id++;
337
338 return 0;
339}
340late_initcall(init_oops_id);
341
342void print_oops_end_marker(void)
343{
344 init_oops_id();
345 printk(KERN_WARNING "---[ end trace %016llx ]---\n",
346 (unsigned long long)oops_id);
347}
348
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352
353void oops_exit(void)
354{
355 do_oops_enter_exit();
356 print_oops_end_marker();
357 kmsg_dump(KMSG_DUMP_OOPS);
358}
359
360#ifdef WANT_WARN_ON_SLOWPATH
361struct slowpath_args {
362 const char *fmt;
363 va_list args;
364};
365
366static void warn_slowpath_common(const char *file, int line, void *caller,
367 unsigned taint, struct slowpath_args *args)
368{
369 const char *board;
370
371 printk(KERN_WARNING "------------[ cut here ]------------\n");
372 printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);
373 board = dmi_get_system_info(DMI_PRODUCT_NAME);
374 if (board)
375 printk(KERN_WARNING "Hardware name: %s\n", board);
376
377 if (args)
378 vprintk(args->fmt, args->args);
379
380 print_modules();
381 dump_stack();
382 print_oops_end_marker();
383 add_taint(taint);
384}
385
386void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
387{
388 struct slowpath_args args;
389
390 args.fmt = fmt;
391 va_start(args.args, fmt);
392 warn_slowpath_common(file, line, __builtin_return_address(0),
393 TAINT_WARN, &args);
394 va_end(args.args);
395}
396EXPORT_SYMBOL(warn_slowpath_fmt);
397
398void warn_slowpath_fmt_taint(const char *file, int line,
399 unsigned taint, const char *fmt, ...)
400{
401 struct slowpath_args args;
402
403 args.fmt = fmt;
404 va_start(args.args, fmt);
405 warn_slowpath_common(file, line, __builtin_return_address(0),
406 taint, &args);
407 va_end(args.args);
408}
409EXPORT_SYMBOL(warn_slowpath_fmt_taint);
410
411void warn_slowpath_null(const char *file, int line)
412{
413 warn_slowpath_common(file, line, __builtin_return_address(0),
414 TAINT_WARN, NULL);
415}
416EXPORT_SYMBOL(warn_slowpath_null);
417#endif
418
419#ifdef CONFIG_CC_STACKPROTECTOR
420
421
422
423
424
425void __stack_chk_fail(void)
426{
427 panic("stack-protector: Kernel stack is corrupted in: %p\n",
428 __builtin_return_address(0));
429}
430EXPORT_SYMBOL(__stack_chk_fail);
431
432#endif
433
434core_param(panic, panic_timeout, int, 0644);
435core_param(pause_on_oops, pause_on_oops, int, 0644);
436