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Commit | Line | Data |
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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> |
de7edd31 | 18 | #include <linux/ftrace.h> |
1da177e4 | 19 | #include <linux/reboot.h> |
c95dbf27 IM |
20 | #include <linux/delay.h> |
21 | #include <linux/kexec.h> | |
22 | #include <linux/sched.h> | |
1da177e4 | 23 | #include <linux/sysrq.h> |
c95dbf27 | 24 | #include <linux/init.h> |
1da177e4 | 25 | #include <linux/nmi.h> |
08d78658 | 26 | #include <linux/console.h> |
2553b67a | 27 | #include <linux/bug.h> |
1da177e4 | 28 | |
c7ff0d9c TS |
29 | #define PANIC_TIMER_STEP 100 |
30 | #define PANIC_BLINK_SPD 18 | |
31 | ||
2a01bb38 | 32 | int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE; |
25ddbb18 | 33 | static unsigned long tainted_mask; |
dd287796 AM |
34 | static int pause_on_oops; |
35 | static int pause_on_oops_flag; | |
36 | static DEFINE_SPINLOCK(pause_on_oops_lock); | |
5375b708 | 37 | bool crash_kexec_post_notifiers; |
9e3961a0 | 38 | int panic_on_warn __read_mostly; |
1da177e4 | 39 | |
5800dc3c | 40 | int panic_timeout = CONFIG_PANIC_TIMEOUT; |
81e88fdc | 41 | EXPORT_SYMBOL_GPL(panic_timeout); |
1da177e4 | 42 | |
e041c683 | 43 | ATOMIC_NOTIFIER_HEAD(panic_notifier_list); |
1da177e4 LT |
44 | |
45 | EXPORT_SYMBOL(panic_notifier_list); | |
46 | ||
c7ff0d9c | 47 | static long no_blink(int state) |
8aeee85a | 48 | { |
c7ff0d9c | 49 | return 0; |
8aeee85a AB |
50 | } |
51 | ||
c7ff0d9c TS |
52 | /* Returns how long it waited in ms */ |
53 | long (*panic_blink)(int state); | |
54 | EXPORT_SYMBOL(panic_blink); | |
55 | ||
93e13a36 MH |
56 | /* |
57 | * Stop ourself in panic -- architecture code may override this | |
58 | */ | |
59 | void __weak panic_smp_self_stop(void) | |
60 | { | |
61 | while (1) | |
62 | cpu_relax(); | |
63 | } | |
64 | ||
58c5661f HK |
65 | /* |
66 | * Stop ourselves in NMI context if another CPU has already panicked. Arch code | |
67 | * may override this to prepare for crash dumping, e.g. save regs info. | |
68 | */ | |
69 | void __weak nmi_panic_self_stop(struct pt_regs *regs) | |
70 | { | |
71 | panic_smp_self_stop(); | |
72 | } | |
73 | ||
0ee59413 HK |
74 | /* |
75 | * Stop other CPUs in panic. Architecture dependent code may override this | |
76 | * with more suitable version. For example, if the architecture supports | |
77 | * crash dump, it should save registers of each stopped CPU and disable | |
78 | * per-CPU features such as virtualization extensions. | |
79 | */ | |
80 | void __weak crash_smp_send_stop(void) | |
81 | { | |
82 | static int cpus_stopped; | |
83 | ||
84 | /* | |
85 | * This function can be called twice in panic path, but obviously | |
86 | * we execute this only once. | |
87 | */ | |
88 | if (cpus_stopped) | |
89 | return; | |
90 | ||
91 | /* | |
92 | * Note smp_send_stop is the usual smp shutdown function, which | |
93 | * unfortunately means it may not be hardened to work in a panic | |
94 | * situation. | |
95 | */ | |
96 | smp_send_stop(); | |
97 | cpus_stopped = 1; | |
98 | } | |
99 | ||
1717f209 HK |
100 | atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID); |
101 | ||
ebc41f20 HK |
102 | /* |
103 | * A variant of panic() called from NMI context. We return if we've already | |
104 | * panicked on this CPU. If another CPU already panicked, loop in | |
105 | * nmi_panic_self_stop() which can provide architecture dependent code such | |
106 | * as saving register state for crash dump. | |
107 | */ | |
108 | void nmi_panic(struct pt_regs *regs, const char *msg) | |
109 | { | |
110 | int old_cpu, cpu; | |
111 | ||
112 | cpu = raw_smp_processor_id(); | |
113 | old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); | |
114 | ||
115 | if (old_cpu == PANIC_CPU_INVALID) | |
116 | panic("%s", msg); | |
117 | else if (old_cpu != cpu) | |
118 | nmi_panic_self_stop(regs); | |
119 | } | |
120 | EXPORT_SYMBOL(nmi_panic); | |
121 | ||
1da177e4 LT |
122 | /** |
123 | * panic - halt the system | |
124 | * @fmt: The text string to print | |
125 | * | |
126 | * Display a message, then perform cleanups. | |
127 | * | |
128 | * This function never returns. | |
129 | */ | |
9402c95f | 130 | void panic(const char *fmt, ...) |
1da177e4 | 131 | { |
1da177e4 LT |
132 | static char buf[1024]; |
133 | va_list args; | |
c7ff0d9c TS |
134 | long i, i_next = 0; |
135 | int state = 0; | |
1717f209 | 136 | int old_cpu, this_cpu; |
b26e27dd | 137 | bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers; |
1da177e4 | 138 | |
190320c3 VM |
139 | /* |
140 | * Disable local interrupts. This will prevent panic_smp_self_stop | |
141 | * from deadlocking the first cpu that invokes the panic, since | |
142 | * there is nothing to prevent an interrupt handler (that runs | |
1717f209 | 143 | * after setting panic_cpu) from invoking panic() again. |
190320c3 VM |
144 | */ |
145 | local_irq_disable(); | |
146 | ||
dc009d92 | 147 | /* |
c95dbf27 IM |
148 | * It's possible to come here directly from a panic-assertion and |
149 | * not have preempt disabled. Some functions called from here want | |
dc009d92 | 150 | * preempt to be disabled. No point enabling it later though... |
93e13a36 MH |
151 | * |
152 | * Only one CPU is allowed to execute the panic code from here. For | |
153 | * multiple parallel invocations of panic, all other CPUs either | |
154 | * stop themself or will wait until they are stopped by the 1st CPU | |
155 | * with smp_send_stop(). | |
1717f209 HK |
156 | * |
157 | * `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which | |
158 | * comes here, so go ahead. | |
159 | * `old_cpu == this_cpu' means we came from nmi_panic() which sets | |
160 | * panic_cpu to this CPU. In this case, this is also the 1st CPU. | |
dc009d92 | 161 | */ |
1717f209 HK |
162 | this_cpu = raw_smp_processor_id(); |
163 | old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu); | |
164 | ||
165 | if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu) | |
93e13a36 | 166 | panic_smp_self_stop(); |
dc009d92 | 167 | |
5b530fc1 | 168 | console_verbose(); |
1da177e4 LT |
169 | bust_spinlocks(1); |
170 | va_start(args, fmt); | |
171 | vsnprintf(buf, sizeof(buf), fmt, args); | |
172 | va_end(args); | |
d7c0847f | 173 | pr_emerg("Kernel panic - not syncing: %s\n", buf); |
5cb27301 | 174 | #ifdef CONFIG_DEBUG_BUGVERBOSE |
6e6f0a1f AK |
175 | /* |
176 | * Avoid nested stack-dumping if a panic occurs during oops processing | |
177 | */ | |
026ee1f6 | 178 | if (!test_taint(TAINT_DIE) && oops_in_progress <= 1) |
6e6f0a1f | 179 | dump_stack(); |
5cb27301 | 180 | #endif |
1da177e4 | 181 | |
dc009d92 EB |
182 | /* |
183 | * If we have crashed and we have a crash kernel loaded let it handle | |
184 | * everything else. | |
f06e5153 MH |
185 | * If we want to run this after calling panic_notifiers, pass |
186 | * the "crash_kexec_post_notifiers" option to the kernel. | |
7bbee5ca HK |
187 | * |
188 | * Bypass the panic_cpu check and call __crash_kexec directly. | |
dc009d92 | 189 | */ |
b26e27dd | 190 | if (!_crash_kexec_post_notifiers) { |
cf9b1106 | 191 | printk_nmi_flush_on_panic(); |
7bbee5ca | 192 | __crash_kexec(NULL); |
dc009d92 | 193 | |
0ee59413 HK |
194 | /* |
195 | * Note smp_send_stop is the usual smp shutdown function, which | |
196 | * unfortunately means it may not be hardened to work in a | |
197 | * panic situation. | |
198 | */ | |
199 | smp_send_stop(); | |
200 | } else { | |
201 | /* | |
202 | * If we want to do crash dump after notifier calls and | |
203 | * kmsg_dump, we will need architecture dependent extra | |
204 | * works in addition to stopping other CPUs. | |
205 | */ | |
206 | crash_smp_send_stop(); | |
207 | } | |
1da177e4 | 208 | |
6723734c KC |
209 | /* |
210 | * Run any panic handlers, including those that might need to | |
211 | * add information to the kmsg dump output. | |
212 | */ | |
e041c683 | 213 | atomic_notifier_call_chain(&panic_notifier_list, 0, buf); |
1da177e4 | 214 | |
cf9b1106 PM |
215 | /* Call flush even twice. It tries harder with a single online CPU */ |
216 | printk_nmi_flush_on_panic(); | |
6723734c KC |
217 | kmsg_dump(KMSG_DUMP_PANIC); |
218 | ||
f06e5153 MH |
219 | /* |
220 | * If you doubt kdump always works fine in any situation, | |
221 | * "crash_kexec_post_notifiers" offers you a chance to run | |
222 | * panic_notifiers and dumping kmsg before kdump. | |
223 | * Note: since some panic_notifiers can make crashed kernel | |
224 | * more unstable, it can increase risks of the kdump failure too. | |
7bbee5ca HK |
225 | * |
226 | * Bypass the panic_cpu check and call __crash_kexec directly. | |
f06e5153 | 227 | */ |
b26e27dd | 228 | if (_crash_kexec_post_notifiers) |
7bbee5ca | 229 | __crash_kexec(NULL); |
f06e5153 | 230 | |
d014e889 AK |
231 | bust_spinlocks(0); |
232 | ||
08d78658 VK |
233 | /* |
234 | * We may have ended up stopping the CPU holding the lock (in | |
235 | * smp_send_stop()) while still having some valuable data in the console | |
236 | * buffer. Try to acquire the lock then release it regardless of the | |
7625b3a0 VK |
237 | * result. The release will also print the buffers out. Locks debug |
238 | * should be disabled to avoid reporting bad unlock balance when | |
239 | * panic() is not being callled from OOPS. | |
08d78658 | 240 | */ |
7625b3a0 | 241 | debug_locks_off(); |
8d91f8b1 | 242 | console_flush_on_panic(); |
08d78658 | 243 | |
c7ff0d9c TS |
244 | if (!panic_blink) |
245 | panic_blink = no_blink; | |
246 | ||
dc009d92 | 247 | if (panic_timeout > 0) { |
1da177e4 | 248 | /* |
c95dbf27 IM |
249 | * Delay timeout seconds before rebooting the machine. |
250 | * We can't use the "normal" timers since we just panicked. | |
251 | */ | |
ff7a28a0 | 252 | pr_emerg("Rebooting in %d seconds..\n", panic_timeout); |
c95dbf27 | 253 | |
c7ff0d9c | 254 | for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) { |
1da177e4 | 255 | touch_nmi_watchdog(); |
c7ff0d9c TS |
256 | if (i >= i_next) { |
257 | i += panic_blink(state ^= 1); | |
258 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
259 | } | |
260 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 | 261 | } |
4302fbc8 HD |
262 | } |
263 | if (panic_timeout != 0) { | |
c95dbf27 IM |
264 | /* |
265 | * This will not be a clean reboot, with everything | |
266 | * shutting down. But if there is a chance of | |
267 | * rebooting the system it will be rebooted. | |
1da177e4 | 268 | */ |
2f048ea8 | 269 | emergency_restart(); |
1da177e4 LT |
270 | } |
271 | #ifdef __sparc__ | |
272 | { | |
273 | extern int stop_a_enabled; | |
a271c241 | 274 | /* Make sure the user can actually press Stop-A (L1-A) */ |
1da177e4 | 275 | stop_a_enabled = 1; |
d7c0847f | 276 | pr_emerg("Press Stop-A (L1-A) to return to the boot prom\n"); |
1da177e4 LT |
277 | } |
278 | #endif | |
347a8dc3 | 279 | #if defined(CONFIG_S390) |
c95dbf27 IM |
280 | { |
281 | unsigned long caller; | |
282 | ||
283 | caller = (unsigned long)__builtin_return_address(0); | |
284 | disabled_wait(caller); | |
285 | } | |
1da177e4 | 286 | #endif |
d7c0847f | 287 | pr_emerg("---[ end Kernel panic - not syncing: %s\n", buf); |
1da177e4 | 288 | local_irq_enable(); |
c7ff0d9c | 289 | for (i = 0; ; i += PANIC_TIMER_STEP) { |
c22db941 | 290 | touch_softlockup_watchdog(); |
c7ff0d9c TS |
291 | if (i >= i_next) { |
292 | i += panic_blink(state ^= 1); | |
293 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
294 | } | |
295 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 LT |
296 | } |
297 | } | |
298 | ||
299 | EXPORT_SYMBOL(panic); | |
300 | ||
7fd8329b PM |
301 | /* |
302 | * TAINT_FORCED_RMMOD could be a per-module flag but the module | |
303 | * is being removed anyway. | |
304 | */ | |
305 | const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = { | |
306 | { 'P', 'G', true }, /* TAINT_PROPRIETARY_MODULE */ | |
307 | { 'F', ' ', true }, /* TAINT_FORCED_MODULE */ | |
308 | { 'S', ' ', false }, /* TAINT_CPU_OUT_OF_SPEC */ | |
309 | { 'R', ' ', false }, /* TAINT_FORCED_RMMOD */ | |
310 | { 'M', ' ', false }, /* TAINT_MACHINE_CHECK */ | |
311 | { 'B', ' ', false }, /* TAINT_BAD_PAGE */ | |
312 | { 'U', ' ', false }, /* TAINT_USER */ | |
313 | { 'D', ' ', false }, /* TAINT_DIE */ | |
314 | { 'A', ' ', false }, /* TAINT_OVERRIDDEN_ACPI_TABLE */ | |
315 | { 'W', ' ', false }, /* TAINT_WARN */ | |
316 | { 'C', ' ', true }, /* TAINT_CRAP */ | |
317 | { 'I', ' ', false }, /* TAINT_FIRMWARE_WORKAROUND */ | |
318 | { 'O', ' ', true }, /* TAINT_OOT_MODULE */ | |
319 | { 'E', ' ', true }, /* TAINT_UNSIGNED_MODULE */ | |
320 | { 'L', ' ', false }, /* TAINT_SOFTLOCKUP */ | |
321 | { 'K', ' ', true }, /* TAINT_LIVEPATCH */ | |
25ddbb18 AK |
322 | }; |
323 | ||
1da177e4 LT |
324 | /** |
325 | * print_tainted - return a string to represent the kernel taint state. | |
326 | * | |
327 | * 'P' - Proprietary module has been loaded. | |
328 | * 'F' - Module has been forcibly loaded. | |
329 | * 'S' - SMP with CPUs not designed for SMP. | |
330 | * 'R' - User forced a module unload. | |
9aa5e993 | 331 | * 'M' - System experienced a machine check exception. |
1da177e4 | 332 | * 'B' - System has hit bad_page. |
34f5a398 | 333 | * 'U' - Userspace-defined naughtiness. |
a8005992 | 334 | * 'D' - Kernel has oopsed before |
95b570c9 NH |
335 | * 'A' - ACPI table overridden. |
336 | * 'W' - Taint on warning. | |
061b1bd3 | 337 | * 'C' - modules from drivers/staging are loaded. |
92946bc7 | 338 | * 'I' - Working around severe firmware bug. |
2449b8ba | 339 | * 'O' - Out-of-tree module has been loaded. |
57673c2b | 340 | * 'E' - Unsigned module has been loaded. |
bc53a3f4 | 341 | * 'L' - A soft lockup has previously occurred. |
c5f45465 | 342 | * 'K' - Kernel has been live patched. |
1da177e4 | 343 | * |
fe002a41 | 344 | * The string is overwritten by the next call to print_tainted(). |
1da177e4 | 345 | */ |
1da177e4 LT |
346 | const char *print_tainted(void) |
347 | { | |
7fd8329b | 348 | static char buf[TAINT_FLAGS_COUNT + sizeof("Tainted: ")]; |
25ddbb18 AK |
349 | |
350 | if (tainted_mask) { | |
351 | char *s; | |
352 | int i; | |
353 | ||
354 | s = buf + sprintf(buf, "Tainted: "); | |
7fd8329b PM |
355 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { |
356 | const struct taint_flag *t = &taint_flags[i]; | |
357 | *s++ = test_bit(i, &tainted_mask) ? | |
5eb7c0d0 | 358 | t->c_true : t->c_false; |
25ddbb18 AK |
359 | } |
360 | *s = 0; | |
361 | } else | |
1da177e4 | 362 | snprintf(buf, sizeof(buf), "Not tainted"); |
c95dbf27 IM |
363 | |
364 | return buf; | |
1da177e4 LT |
365 | } |
366 | ||
25ddbb18 | 367 | int test_taint(unsigned flag) |
1da177e4 | 368 | { |
25ddbb18 AK |
369 | return test_bit(flag, &tainted_mask); |
370 | } | |
371 | EXPORT_SYMBOL(test_taint); | |
372 | ||
373 | unsigned long get_taint(void) | |
374 | { | |
375 | return tainted_mask; | |
1da177e4 | 376 | } |
dd287796 | 377 | |
373d4d09 RR |
378 | /** |
379 | * add_taint: add a taint flag if not already set. | |
380 | * @flag: one of the TAINT_* constants. | |
381 | * @lockdep_ok: whether lock debugging is still OK. | |
382 | * | |
383 | * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for | |
384 | * some notewortht-but-not-corrupting cases, it can be set to true. | |
385 | */ | |
386 | void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) | |
dd287796 | 387 | { |
373d4d09 | 388 | if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off()) |
d7c0847f | 389 | pr_warn("Disabling lock debugging due to kernel taint\n"); |
9eeba613 | 390 | |
25ddbb18 | 391 | set_bit(flag, &tainted_mask); |
dd287796 | 392 | } |
1da177e4 | 393 | EXPORT_SYMBOL(add_taint); |
dd287796 AM |
394 | |
395 | static void spin_msec(int msecs) | |
396 | { | |
397 | int i; | |
398 | ||
399 | for (i = 0; i < msecs; i++) { | |
400 | touch_nmi_watchdog(); | |
401 | mdelay(1); | |
402 | } | |
403 | } | |
404 | ||
405 | /* | |
406 | * It just happens that oops_enter() and oops_exit() are identically | |
407 | * implemented... | |
408 | */ | |
409 | static void do_oops_enter_exit(void) | |
410 | { | |
411 | unsigned long flags; | |
412 | static int spin_counter; | |
413 | ||
414 | if (!pause_on_oops) | |
415 | return; | |
416 | ||
417 | spin_lock_irqsave(&pause_on_oops_lock, flags); | |
418 | if (pause_on_oops_flag == 0) { | |
419 | /* This CPU may now print the oops message */ | |
420 | pause_on_oops_flag = 1; | |
421 | } else { | |
422 | /* We need to stall this CPU */ | |
423 | if (!spin_counter) { | |
424 | /* This CPU gets to do the counting */ | |
425 | spin_counter = pause_on_oops; | |
426 | do { | |
427 | spin_unlock(&pause_on_oops_lock); | |
428 | spin_msec(MSEC_PER_SEC); | |
429 | spin_lock(&pause_on_oops_lock); | |
430 | } while (--spin_counter); | |
431 | pause_on_oops_flag = 0; | |
432 | } else { | |
433 | /* This CPU waits for a different one */ | |
434 | while (spin_counter) { | |
435 | spin_unlock(&pause_on_oops_lock); | |
436 | spin_msec(1); | |
437 | spin_lock(&pause_on_oops_lock); | |
438 | } | |
439 | } | |
440 | } | |
441 | spin_unlock_irqrestore(&pause_on_oops_lock, flags); | |
442 | } | |
443 | ||
444 | /* | |
c95dbf27 IM |
445 | * Return true if the calling CPU is allowed to print oops-related info. |
446 | * This is a bit racy.. | |
dd287796 AM |
447 | */ |
448 | int oops_may_print(void) | |
449 | { | |
450 | return pause_on_oops_flag == 0; | |
451 | } | |
452 | ||
453 | /* | |
454 | * Called when the architecture enters its oops handler, before it prints | |
c95dbf27 IM |
455 | * anything. If this is the first CPU to oops, and it's oopsing the first |
456 | * time then let it proceed. | |
dd287796 | 457 | * |
c95dbf27 IM |
458 | * This is all enabled by the pause_on_oops kernel boot option. We do all |
459 | * this to ensure that oopses don't scroll off the screen. It has the | |
460 | * side-effect of preventing later-oopsing CPUs from mucking up the display, | |
461 | * too. | |
dd287796 | 462 | * |
c95dbf27 IM |
463 | * It turns out that the CPU which is allowed to print ends up pausing for |
464 | * the right duration, whereas all the other CPUs pause for twice as long: | |
465 | * once in oops_enter(), once in oops_exit(). | |
dd287796 AM |
466 | */ |
467 | void oops_enter(void) | |
468 | { | |
bdff7870 | 469 | tracing_off(); |
c95dbf27 IM |
470 | /* can't trust the integrity of the kernel anymore: */ |
471 | debug_locks_off(); | |
dd287796 AM |
472 | do_oops_enter_exit(); |
473 | } | |
474 | ||
2c3b20e9 AV |
475 | /* |
476 | * 64-bit random ID for oopses: | |
477 | */ | |
478 | static u64 oops_id; | |
479 | ||
480 | static int init_oops_id(void) | |
481 | { | |
482 | if (!oops_id) | |
483 | get_random_bytes(&oops_id, sizeof(oops_id)); | |
d6624f99 AV |
484 | else |
485 | oops_id++; | |
2c3b20e9 AV |
486 | |
487 | return 0; | |
488 | } | |
489 | late_initcall(init_oops_id); | |
490 | ||
863a6049 | 491 | void print_oops_end_marker(void) |
71c33911 AV |
492 | { |
493 | init_oops_id(); | |
d7c0847f | 494 | pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id); |
71c33911 AV |
495 | } |
496 | ||
dd287796 AM |
497 | /* |
498 | * Called when the architecture exits its oops handler, after printing | |
499 | * everything. | |
500 | */ | |
501 | void oops_exit(void) | |
502 | { | |
503 | do_oops_enter_exit(); | |
71c33911 | 504 | print_oops_end_marker(); |
456b565c | 505 | kmsg_dump(KMSG_DUMP_OOPS); |
dd287796 | 506 | } |
3162f751 | 507 | |
2553b67a | 508 | struct warn_args { |
0f6f49a8 | 509 | const char *fmt; |
a8f18b90 | 510 | va_list args; |
0f6f49a8 | 511 | }; |
bd89bb29 | 512 | |
2553b67a JP |
513 | void __warn(const char *file, int line, void *caller, unsigned taint, |
514 | struct pt_regs *regs, struct warn_args *args) | |
0f6f49a8 | 515 | { |
de7edd31 SRRH |
516 | disable_trace_on_warning(); |
517 | ||
dcb6b452 | 518 | pr_warn("------------[ cut here ]------------\n"); |
2553b67a JP |
519 | |
520 | if (file) | |
521 | pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n", | |
522 | raw_smp_processor_id(), current->pid, file, line, | |
523 | caller); | |
524 | else | |
525 | pr_warn("WARNING: CPU: %d PID: %d at %pS\n", | |
526 | raw_smp_processor_id(), current->pid, caller); | |
74853dba | 527 | |
0f6f49a8 LT |
528 | if (args) |
529 | vprintk(args->fmt, args->args); | |
a8f18b90 | 530 | |
9e3961a0 PB |
531 | if (panic_on_warn) { |
532 | /* | |
533 | * This thread may hit another WARN() in the panic path. | |
534 | * Resetting this prevents additional WARN() from panicking the | |
535 | * system on this thread. Other threads are blocked by the | |
536 | * panic_mutex in panic(). | |
537 | */ | |
538 | panic_on_warn = 0; | |
539 | panic("panic_on_warn set ...\n"); | |
540 | } | |
541 | ||
a8f18b90 | 542 | print_modules(); |
2553b67a JP |
543 | |
544 | if (regs) | |
545 | show_regs(regs); | |
546 | else | |
547 | dump_stack(); | |
548 | ||
a8f18b90 | 549 | print_oops_end_marker(); |
2553b67a | 550 | |
373d4d09 RR |
551 | /* Just a warning, don't kill lockdep. */ |
552 | add_taint(taint, LOCKDEP_STILL_OK); | |
a8f18b90 | 553 | } |
0f6f49a8 | 554 | |
2553b67a | 555 | #ifdef WANT_WARN_ON_SLOWPATH |
0f6f49a8 LT |
556 | void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) |
557 | { | |
2553b67a | 558 | struct warn_args args; |
0f6f49a8 LT |
559 | |
560 | args.fmt = fmt; | |
561 | va_start(args.args, fmt); | |
2553b67a JP |
562 | __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL, |
563 | &args); | |
0f6f49a8 LT |
564 | va_end(args.args); |
565 | } | |
57adc4d2 AK |
566 | EXPORT_SYMBOL(warn_slowpath_fmt); |
567 | ||
b2be0527 BH |
568 | void warn_slowpath_fmt_taint(const char *file, int line, |
569 | unsigned taint, const char *fmt, ...) | |
570 | { | |
2553b67a | 571 | struct warn_args args; |
b2be0527 BH |
572 | |
573 | args.fmt = fmt; | |
574 | va_start(args.args, fmt); | |
2553b67a | 575 | __warn(file, line, __builtin_return_address(0), taint, NULL, &args); |
b2be0527 BH |
576 | va_end(args.args); |
577 | } | |
578 | EXPORT_SYMBOL(warn_slowpath_fmt_taint); | |
579 | ||
57adc4d2 AK |
580 | void warn_slowpath_null(const char *file, int line) |
581 | { | |
2553b67a | 582 | __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL, NULL); |
57adc4d2 AK |
583 | } |
584 | EXPORT_SYMBOL(warn_slowpath_null); | |
79b4cc5e AV |
585 | #endif |
586 | ||
3162f751 | 587 | #ifdef CONFIG_CC_STACKPROTECTOR |
54371a43 | 588 | |
3162f751 AV |
589 | /* |
590 | * Called when gcc's -fstack-protector feature is used, and | |
591 | * gcc detects corruption of the on-stack canary value | |
592 | */ | |
a7330c99 | 593 | __visible void __stack_chk_fail(void) |
3162f751 | 594 | { |
517a92c4 IM |
595 | panic("stack-protector: Kernel stack is corrupted in: %p\n", |
596 | __builtin_return_address(0)); | |
3162f751 AV |
597 | } |
598 | EXPORT_SYMBOL(__stack_chk_fail); | |
54371a43 | 599 | |
3162f751 | 600 | #endif |
f44dd164 RR |
601 | |
602 | core_param(panic, panic_timeout, int, 0644); | |
603 | core_param(pause_on_oops, pause_on_oops, int, 0644); | |
9e3961a0 | 604 | core_param(panic_on_warn, panic_on_warn, int, 0644); |
b26e27dd | 605 | core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644); |
f06e5153 | 606 | |
d404ab0a OH |
607 | static int __init oops_setup(char *s) |
608 | { | |
609 | if (!s) | |
610 | return -EINVAL; | |
611 | if (!strcmp(s, "panic")) | |
612 | panic_on_oops = 1; | |
613 | return 0; | |
614 | } | |
615 | early_param("oops", oops_setup); |