Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/panic.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
7 | /* | |
8 | * This function is used through-out the kernel (including mm and fs) | |
9 | * to indicate a major problem. | |
10 | */ | |
c95dbf27 IM |
11 | #include <linux/debug_locks.h> |
12 | #include <linux/interrupt.h> | |
456b565c | 13 | #include <linux/kmsg_dump.h> |
c95dbf27 IM |
14 | #include <linux/kallsyms.h> |
15 | #include <linux/notifier.h> | |
1da177e4 | 16 | #include <linux/module.h> |
c95dbf27 | 17 | #include <linux/random.h> |
1da177e4 | 18 | #include <linux/reboot.h> |
c95dbf27 IM |
19 | #include <linux/delay.h> |
20 | #include <linux/kexec.h> | |
21 | #include <linux/sched.h> | |
1da177e4 | 22 | #include <linux/sysrq.h> |
c95dbf27 | 23 | #include <linux/init.h> |
1da177e4 | 24 | #include <linux/nmi.h> |
3c2a0909 S |
25 | #include <linux/exynos-ss.h> |
26 | #include <asm/core_regs.h> | |
27 | #include "sched/sched.h" | |
f7184747 | 28 | #include <linux/console.h> |
1da177e4 | 29 | |
c7ff0d9c TS |
30 | #define PANIC_TIMER_STEP 100 |
31 | #define PANIC_BLINK_SPD 18 | |
3c2a0909 S |
32 | #if defined(CONFIG_SOC_EXYNOS5422) || defined(CONFIG_SOC_EXYNOS5430) |
33 | extern void show_exynos_pmu(void); | |
34 | #endif | |
35 | #if defined(CONFIG_SOC_EXYNOS5422) || defined(CONFIG_SOC_EXYNOS5430) | |
36 | extern void show_exynos_cmu(void); | |
37 | #endif | |
38 | ||
39 | /* Machine specific panic information string */ | |
40 | char *mach_panic_string; | |
41 | ||
42 | /* Machine specific panic information string */ | |
43 | char *mach_panic_string; | |
c7ff0d9c | 44 | |
2a01bb38 | 45 | int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE; |
25ddbb18 | 46 | static unsigned long tainted_mask; |
dd287796 AM |
47 | static int pause_on_oops; |
48 | static int pause_on_oops_flag; | |
49 | static DEFINE_SPINLOCK(pause_on_oops_lock); | |
1da177e4 | 50 | |
3c2a0909 S |
51 | #ifndef CONFIG_PANIC_TIMEOUT |
52 | #define CONFIG_PANIC_TIMEOUT 0 | |
53 | #endif | |
54 | int panic_timeout = CONFIG_PANIC_TIMEOUT; | |
81e88fdc | 55 | EXPORT_SYMBOL_GPL(panic_timeout); |
1da177e4 | 56 | |
e041c683 | 57 | ATOMIC_NOTIFIER_HEAD(panic_notifier_list); |
1da177e4 LT |
58 | |
59 | EXPORT_SYMBOL(panic_notifier_list); | |
60 | ||
c7ff0d9c | 61 | static long no_blink(int state) |
8aeee85a | 62 | { |
c7ff0d9c | 63 | return 0; |
8aeee85a AB |
64 | } |
65 | ||
c7ff0d9c TS |
66 | /* Returns how long it waited in ms */ |
67 | long (*panic_blink)(int state); | |
68 | EXPORT_SYMBOL(panic_blink); | |
69 | ||
93e13a36 MH |
70 | /* |
71 | * Stop ourself in panic -- architecture code may override this | |
72 | */ | |
73 | void __weak panic_smp_self_stop(void) | |
74 | { | |
75 | while (1) | |
76 | cpu_relax(); | |
77 | } | |
78 | ||
1da177e4 LT |
79 | /** |
80 | * panic - halt the system | |
81 | * @fmt: The text string to print | |
82 | * | |
83 | * Display a message, then perform cleanups. | |
84 | * | |
85 | * This function never returns. | |
86 | */ | |
9402c95f | 87 | void panic(const char *fmt, ...) |
1da177e4 | 88 | { |
93e13a36 | 89 | static DEFINE_SPINLOCK(panic_lock); |
1da177e4 LT |
90 | static char buf[1024]; |
91 | va_list args; | |
c7ff0d9c TS |
92 | long i, i_next = 0; |
93 | int state = 0; | |
1da177e4 | 94 | |
3c2a0909 S |
95 | #ifdef CONFIG_EXYNOS_CORESIGHT_ETM |
96 | exynos_trace_stop(); | |
97 | #endif | |
190320c3 VM |
98 | /* |
99 | * Disable local interrupts. This will prevent panic_smp_self_stop | |
100 | * from deadlocking the first cpu that invokes the panic, since | |
101 | * there is nothing to prevent an interrupt handler (that runs | |
102 | * after the panic_lock is acquired) from invoking panic again. | |
103 | */ | |
104 | local_irq_disable(); | |
105 | ||
dc009d92 | 106 | /* |
c95dbf27 IM |
107 | * It's possible to come here directly from a panic-assertion and |
108 | * not have preempt disabled. Some functions called from here want | |
dc009d92 | 109 | * preempt to be disabled. No point enabling it later though... |
93e13a36 MH |
110 | * |
111 | * Only one CPU is allowed to execute the panic code from here. For | |
112 | * multiple parallel invocations of panic, all other CPUs either | |
113 | * stop themself or will wait until they are stopped by the 1st CPU | |
114 | * with smp_send_stop(). | |
dc009d92 | 115 | */ |
93e13a36 MH |
116 | if (!spin_trylock(&panic_lock)) |
117 | panic_smp_self_stop(); | |
dc009d92 | 118 | |
5b530fc1 | 119 | console_verbose(); |
1da177e4 LT |
120 | bust_spinlocks(1); |
121 | va_start(args, fmt); | |
122 | vsnprintf(buf, sizeof(buf), fmt, args); | |
123 | va_end(args); | |
124 | printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf); | |
3c2a0909 S |
125 | |
126 | exynos_ss_prepare_panic(); | |
127 | exynos_ss_dump_panic(); | |
5cb27301 | 128 | #ifdef CONFIG_DEBUG_BUGVERBOSE |
6e6f0a1f AK |
129 | /* |
130 | * Avoid nested stack-dumping if a panic occurs during oops processing | |
131 | */ | |
026ee1f6 | 132 | if (!test_taint(TAINT_DIE) && oops_in_progress <= 1) |
6e6f0a1f | 133 | dump_stack(); |
5cb27301 | 134 | #endif |
1da177e4 | 135 | |
3c2a0909 S |
136 | #if defined(CONFIG_SOC_EXYNOS5422) || defined(CONFIG_SOC_EXYNOS5430) |
137 | show_exynos_pmu(); | |
138 | #endif | |
139 | #if defined(CONFIG_SOC_EXYNOS5422) || defined(CONFIG_SOC_EXYNOS5430) | |
140 | show_exynos_cmu(); | |
141 | #endif | |
142 | sysrq_sched_debug_show(); | |
143 | ||
dc009d92 EB |
144 | /* |
145 | * If we have crashed and we have a crash kernel loaded let it handle | |
146 | * everything else. | |
147 | * Do we want to call this before we try to display a message? | |
148 | */ | |
6e274d14 | 149 | crash_kexec(NULL); |
dc009d92 | 150 | |
dc009d92 EB |
151 | /* |
152 | * Note smp_send_stop is the usual smp shutdown function, which | |
153 | * unfortunately means it may not be hardened to work in a panic | |
154 | * situation. | |
155 | */ | |
1da177e4 | 156 | smp_send_stop(); |
1da177e4 | 157 | |
62be73ea SA |
158 | kmsg_dump(KMSG_DUMP_PANIC); |
159 | ||
3c2a0909 S |
160 | exynos_cs_show_pcval(); |
161 | ||
e041c683 | 162 | atomic_notifier_call_chain(&panic_notifier_list, 0, buf); |
1da177e4 | 163 | |
3c2a0909 S |
164 | exynos_ss_post_panic(); |
165 | ||
d014e889 AK |
166 | bust_spinlocks(0); |
167 | ||
f7184747 TH |
168 | console_flush_on_panic(); |
169 | ||
c7ff0d9c TS |
170 | if (!panic_blink) |
171 | panic_blink = no_blink; | |
172 | ||
dc009d92 | 173 | if (panic_timeout > 0) { |
1da177e4 | 174 | /* |
c95dbf27 IM |
175 | * Delay timeout seconds before rebooting the machine. |
176 | * We can't use the "normal" timers since we just panicked. | |
177 | */ | |
178 | printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout); | |
179 | ||
c7ff0d9c | 180 | for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) { |
1da177e4 | 181 | touch_nmi_watchdog(); |
c7ff0d9c TS |
182 | if (i >= i_next) { |
183 | i += panic_blink(state ^= 1); | |
184 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
185 | } | |
186 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 | 187 | } |
4302fbc8 HD |
188 | } |
189 | if (panic_timeout != 0) { | |
c95dbf27 IM |
190 | /* |
191 | * This will not be a clean reboot, with everything | |
192 | * shutting down. But if there is a chance of | |
193 | * rebooting the system it will be rebooted. | |
1da177e4 | 194 | */ |
2f048ea8 | 195 | emergency_restart(); |
1da177e4 LT |
196 | } |
197 | #ifdef __sparc__ | |
198 | { | |
199 | extern int stop_a_enabled; | |
a271c241 | 200 | /* Make sure the user can actually press Stop-A (L1-A) */ |
1da177e4 | 201 | stop_a_enabled = 1; |
a271c241 | 202 | printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n"); |
1da177e4 LT |
203 | } |
204 | #endif | |
347a8dc3 | 205 | #if defined(CONFIG_S390) |
c95dbf27 IM |
206 | { |
207 | unsigned long caller; | |
208 | ||
209 | caller = (unsigned long)__builtin_return_address(0); | |
210 | disabled_wait(caller); | |
211 | } | |
1da177e4 LT |
212 | #endif |
213 | local_irq_enable(); | |
c7ff0d9c | 214 | for (i = 0; ; i += PANIC_TIMER_STEP) { |
c22db941 | 215 | touch_softlockup_watchdog(); |
c7ff0d9c TS |
216 | if (i >= i_next) { |
217 | i += panic_blink(state ^= 1); | |
218 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
219 | } | |
220 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 LT |
221 | } |
222 | } | |
223 | ||
224 | EXPORT_SYMBOL(panic); | |
225 | ||
c277e63f | 226 | |
25ddbb18 | 227 | struct tnt { |
c95dbf27 IM |
228 | u8 bit; |
229 | char true; | |
230 | char false; | |
25ddbb18 AK |
231 | }; |
232 | ||
233 | static const struct tnt tnts[] = { | |
c95dbf27 IM |
234 | { TAINT_PROPRIETARY_MODULE, 'P', 'G' }, |
235 | { TAINT_FORCED_MODULE, 'F', ' ' }, | |
236 | { TAINT_UNSAFE_SMP, 'S', ' ' }, | |
237 | { TAINT_FORCED_RMMOD, 'R', ' ' }, | |
238 | { TAINT_MACHINE_CHECK, 'M', ' ' }, | |
239 | { TAINT_BAD_PAGE, 'B', ' ' }, | |
240 | { TAINT_USER, 'U', ' ' }, | |
241 | { TAINT_DIE, 'D', ' ' }, | |
242 | { TAINT_OVERRIDDEN_ACPI_TABLE, 'A', ' ' }, | |
243 | { TAINT_WARN, 'W', ' ' }, | |
244 | { TAINT_CRAP, 'C', ' ' }, | |
92946bc7 | 245 | { TAINT_FIRMWARE_WORKAROUND, 'I', ' ' }, |
2449b8ba | 246 | { TAINT_OOT_MODULE, 'O', ' ' }, |
25ddbb18 AK |
247 | }; |
248 | ||
1da177e4 LT |
249 | /** |
250 | * print_tainted - return a string to represent the kernel taint state. | |
251 | * | |
252 | * 'P' - Proprietary module has been loaded. | |
253 | * 'F' - Module has been forcibly loaded. | |
254 | * 'S' - SMP with CPUs not designed for SMP. | |
255 | * 'R' - User forced a module unload. | |
9aa5e993 | 256 | * 'M' - System experienced a machine check exception. |
1da177e4 | 257 | * 'B' - System has hit bad_page. |
34f5a398 | 258 | * 'U' - Userspace-defined naughtiness. |
a8005992 | 259 | * 'D' - Kernel has oopsed before |
95b570c9 NH |
260 | * 'A' - ACPI table overridden. |
261 | * 'W' - Taint on warning. | |
061b1bd3 | 262 | * 'C' - modules from drivers/staging are loaded. |
92946bc7 | 263 | * 'I' - Working around severe firmware bug. |
2449b8ba | 264 | * 'O' - Out-of-tree module has been loaded. |
1da177e4 | 265 | * |
fe002a41 | 266 | * The string is overwritten by the next call to print_tainted(). |
1da177e4 | 267 | */ |
1da177e4 LT |
268 | const char *print_tainted(void) |
269 | { | |
25ddbb18 AK |
270 | static char buf[ARRAY_SIZE(tnts) + sizeof("Tainted: ") + 1]; |
271 | ||
272 | if (tainted_mask) { | |
273 | char *s; | |
274 | int i; | |
275 | ||
276 | s = buf + sprintf(buf, "Tainted: "); | |
277 | for (i = 0; i < ARRAY_SIZE(tnts); i++) { | |
278 | const struct tnt *t = &tnts[i]; | |
279 | *s++ = test_bit(t->bit, &tainted_mask) ? | |
280 | t->true : t->false; | |
281 | } | |
282 | *s = 0; | |
283 | } else | |
1da177e4 | 284 | snprintf(buf, sizeof(buf), "Not tainted"); |
c95dbf27 IM |
285 | |
286 | return buf; | |
1da177e4 LT |
287 | } |
288 | ||
25ddbb18 | 289 | int test_taint(unsigned flag) |
1da177e4 | 290 | { |
25ddbb18 AK |
291 | return test_bit(flag, &tainted_mask); |
292 | } | |
293 | EXPORT_SYMBOL(test_taint); | |
294 | ||
295 | unsigned long get_taint(void) | |
296 | { | |
297 | return tainted_mask; | |
1da177e4 | 298 | } |
dd287796 | 299 | |
373d4d09 RR |
300 | /** |
301 | * add_taint: add a taint flag if not already set. | |
302 | * @flag: one of the TAINT_* constants. | |
303 | * @lockdep_ok: whether lock debugging is still OK. | |
304 | * | |
305 | * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for | |
306 | * some notewortht-but-not-corrupting cases, it can be set to true. | |
307 | */ | |
308 | void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) | |
dd287796 | 309 | { |
373d4d09 RR |
310 | if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off()) |
311 | printk(KERN_WARNING | |
312 | "Disabling lock debugging due to kernel taint\n"); | |
9eeba613 | 313 | |
25ddbb18 | 314 | set_bit(flag, &tainted_mask); |
dd287796 | 315 | } |
1da177e4 | 316 | EXPORT_SYMBOL(add_taint); |
dd287796 AM |
317 | |
318 | static void spin_msec(int msecs) | |
319 | { | |
320 | int i; | |
321 | ||
322 | for (i = 0; i < msecs; i++) { | |
323 | touch_nmi_watchdog(); | |
324 | mdelay(1); | |
325 | } | |
326 | } | |
327 | ||
328 | /* | |
329 | * It just happens that oops_enter() and oops_exit() are identically | |
330 | * implemented... | |
331 | */ | |
332 | static void do_oops_enter_exit(void) | |
333 | { | |
334 | unsigned long flags; | |
335 | static int spin_counter; | |
336 | ||
337 | if (!pause_on_oops) | |
338 | return; | |
339 | ||
340 | spin_lock_irqsave(&pause_on_oops_lock, flags); | |
341 | if (pause_on_oops_flag == 0) { | |
342 | /* This CPU may now print the oops message */ | |
343 | pause_on_oops_flag = 1; | |
344 | } else { | |
345 | /* We need to stall this CPU */ | |
346 | if (!spin_counter) { | |
347 | /* This CPU gets to do the counting */ | |
348 | spin_counter = pause_on_oops; | |
349 | do { | |
350 | spin_unlock(&pause_on_oops_lock); | |
351 | spin_msec(MSEC_PER_SEC); | |
352 | spin_lock(&pause_on_oops_lock); | |
353 | } while (--spin_counter); | |
354 | pause_on_oops_flag = 0; | |
355 | } else { | |
356 | /* This CPU waits for a different one */ | |
357 | while (spin_counter) { | |
358 | spin_unlock(&pause_on_oops_lock); | |
359 | spin_msec(1); | |
360 | spin_lock(&pause_on_oops_lock); | |
361 | } | |
362 | } | |
363 | } | |
364 | spin_unlock_irqrestore(&pause_on_oops_lock, flags); | |
365 | } | |
366 | ||
367 | /* | |
c95dbf27 IM |
368 | * Return true if the calling CPU is allowed to print oops-related info. |
369 | * This is a bit racy.. | |
dd287796 AM |
370 | */ |
371 | int oops_may_print(void) | |
372 | { | |
373 | return pause_on_oops_flag == 0; | |
374 | } | |
375 | ||
376 | /* | |
377 | * Called when the architecture enters its oops handler, before it prints | |
c95dbf27 IM |
378 | * anything. If this is the first CPU to oops, and it's oopsing the first |
379 | * time then let it proceed. | |
dd287796 | 380 | * |
c95dbf27 IM |
381 | * This is all enabled by the pause_on_oops kernel boot option. We do all |
382 | * this to ensure that oopses don't scroll off the screen. It has the | |
383 | * side-effect of preventing later-oopsing CPUs from mucking up the display, | |
384 | * too. | |
dd287796 | 385 | * |
c95dbf27 IM |
386 | * It turns out that the CPU which is allowed to print ends up pausing for |
387 | * the right duration, whereas all the other CPUs pause for twice as long: | |
388 | * once in oops_enter(), once in oops_exit(). | |
dd287796 AM |
389 | */ |
390 | void oops_enter(void) | |
391 | { | |
bdff7870 | 392 | tracing_off(); |
c95dbf27 IM |
393 | /* can't trust the integrity of the kernel anymore: */ |
394 | debug_locks_off(); | |
dd287796 AM |
395 | do_oops_enter_exit(); |
396 | } | |
397 | ||
2c3b20e9 AV |
398 | /* |
399 | * 64-bit random ID for oopses: | |
400 | */ | |
401 | static u64 oops_id; | |
402 | ||
403 | static int init_oops_id(void) | |
404 | { | |
405 | if (!oops_id) | |
406 | get_random_bytes(&oops_id, sizeof(oops_id)); | |
d6624f99 AV |
407 | else |
408 | oops_id++; | |
2c3b20e9 AV |
409 | |
410 | return 0; | |
411 | } | |
412 | late_initcall(init_oops_id); | |
413 | ||
863a6049 | 414 | void print_oops_end_marker(void) |
71c33911 AV |
415 | { |
416 | init_oops_id(); | |
3c2a0909 S |
417 | |
418 | if (mach_panic_string) | |
419 | printk(KERN_WARNING "Board Information: %s\n", | |
420 | mach_panic_string); | |
421 | ||
71c33911 AV |
422 | printk(KERN_WARNING "---[ end trace %016llx ]---\n", |
423 | (unsigned long long)oops_id); | |
424 | } | |
425 | ||
dd287796 AM |
426 | /* |
427 | * Called when the architecture exits its oops handler, after printing | |
428 | * everything. | |
429 | */ | |
430 | void oops_exit(void) | |
431 | { | |
432 | do_oops_enter_exit(); | |
71c33911 | 433 | print_oops_end_marker(); |
456b565c | 434 | kmsg_dump(KMSG_DUMP_OOPS); |
dd287796 | 435 | } |
3162f751 | 436 | |
79b4cc5e | 437 | #ifdef WANT_WARN_ON_SLOWPATH |
0f6f49a8 LT |
438 | struct slowpath_args { |
439 | const char *fmt; | |
a8f18b90 | 440 | va_list args; |
0f6f49a8 | 441 | }; |
bd89bb29 | 442 | |
b2be0527 BH |
443 | static void warn_slowpath_common(const char *file, int line, void *caller, |
444 | unsigned taint, struct slowpath_args *args) | |
0f6f49a8 | 445 | { |
a8f18b90 | 446 | printk(KERN_WARNING "------------[ cut here ]------------\n"); |
0f6f49a8 | 447 | printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller); |
74853dba | 448 | |
0f6f49a8 LT |
449 | if (args) |
450 | vprintk(args->fmt, args->args); | |
a8f18b90 AV |
451 | |
452 | print_modules(); | |
453 | dump_stack(); | |
454 | print_oops_end_marker(); | |
373d4d09 RR |
455 | /* Just a warning, don't kill lockdep. */ |
456 | add_taint(taint, LOCKDEP_STILL_OK); | |
a8f18b90 | 457 | } |
0f6f49a8 LT |
458 | |
459 | void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) | |
460 | { | |
461 | struct slowpath_args args; | |
462 | ||
463 | args.fmt = fmt; | |
464 | va_start(args.args, fmt); | |
b2be0527 BH |
465 | warn_slowpath_common(file, line, __builtin_return_address(0), |
466 | TAINT_WARN, &args); | |
0f6f49a8 LT |
467 | va_end(args.args); |
468 | } | |
57adc4d2 AK |
469 | EXPORT_SYMBOL(warn_slowpath_fmt); |
470 | ||
b2be0527 BH |
471 | void warn_slowpath_fmt_taint(const char *file, int line, |
472 | unsigned taint, const char *fmt, ...) | |
473 | { | |
474 | struct slowpath_args args; | |
475 | ||
476 | args.fmt = fmt; | |
477 | va_start(args.args, fmt); | |
478 | warn_slowpath_common(file, line, __builtin_return_address(0), | |
479 | taint, &args); | |
480 | va_end(args.args); | |
481 | } | |
482 | EXPORT_SYMBOL(warn_slowpath_fmt_taint); | |
483 | ||
57adc4d2 AK |
484 | void warn_slowpath_null(const char *file, int line) |
485 | { | |
b2be0527 BH |
486 | warn_slowpath_common(file, line, __builtin_return_address(0), |
487 | TAINT_WARN, NULL); | |
57adc4d2 AK |
488 | } |
489 | EXPORT_SYMBOL(warn_slowpath_null); | |
79b4cc5e AV |
490 | #endif |
491 | ||
3162f751 | 492 | #ifdef CONFIG_CC_STACKPROTECTOR |
54371a43 | 493 | |
3162f751 AV |
494 | /* |
495 | * Called when gcc's -fstack-protector feature is used, and | |
496 | * gcc detects corruption of the on-stack canary value | |
497 | */ | |
498 | void __stack_chk_fail(void) | |
499 | { | |
517a92c4 IM |
500 | panic("stack-protector: Kernel stack is corrupted in: %p\n", |
501 | __builtin_return_address(0)); | |
3162f751 AV |
502 | } |
503 | EXPORT_SYMBOL(__stack_chk_fail); | |
54371a43 | 504 | |
3162f751 | 505 | #endif |
f44dd164 RR |
506 | |
507 | core_param(panic, panic_timeout, int, 0644); | |
508 | core_param(pause_on_oops, pause_on_oops, int, 0644); | |
d404ab0a OH |
509 | |
510 | static int __init oops_setup(char *s) | |
511 | { | |
512 | if (!s) | |
513 | return -EINVAL; | |
514 | if (!strcmp(s, "panic")) | |
515 | panic_on_oops = 1; | |
516 | return 0; | |
517 | } | |
518 | early_param("oops", oops_setup); |