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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 | 11 | #include <linux/debug_locks.h> |
b17b0153 | 12 | #include <linux/sched/debug.h> |
c95dbf27 | 13 | #include <linux/interrupt.h> |
456b565c | 14 | #include <linux/kmsg_dump.h> |
c95dbf27 IM |
15 | #include <linux/kallsyms.h> |
16 | #include <linux/notifier.h> | |
f30ffd9b | 17 | #include <linux/vt_kern.h> |
1da177e4 | 18 | #include <linux/module.h> |
c95dbf27 | 19 | #include <linux/random.h> |
de7edd31 | 20 | #include <linux/ftrace.h> |
1da177e4 | 21 | #include <linux/reboot.h> |
c95dbf27 IM |
22 | #include <linux/delay.h> |
23 | #include <linux/kexec.h> | |
24 | #include <linux/sched.h> | |
1da177e4 | 25 | #include <linux/sysrq.h> |
c95dbf27 | 26 | #include <linux/init.h> |
1da177e4 | 27 | #include <linux/nmi.h> |
08d78658 | 28 | #include <linux/console.h> |
2553b67a | 29 | #include <linux/bug.h> |
7a46ec0e | 30 | #include <linux/ratelimit.h> |
b1fca27d AK |
31 | #include <linux/debugfs.h> |
32 | #include <asm/sections.h> | |
1da177e4 | 33 | |
c7ff0d9c TS |
34 | #define PANIC_TIMER_STEP 100 |
35 | #define PANIC_BLINK_SPD 18 | |
36 | ||
2a01bb38 | 37 | int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE; |
25ddbb18 | 38 | static unsigned long tainted_mask; |
dd287796 AM |
39 | static int pause_on_oops; |
40 | static int pause_on_oops_flag; | |
41 | static DEFINE_SPINLOCK(pause_on_oops_lock); | |
5375b708 | 42 | bool crash_kexec_post_notifiers; |
9e3961a0 | 43 | int panic_on_warn __read_mostly; |
1da177e4 | 44 | |
5800dc3c | 45 | int panic_timeout = CONFIG_PANIC_TIMEOUT; |
81e88fdc | 46 | EXPORT_SYMBOL_GPL(panic_timeout); |
1da177e4 | 47 | |
e041c683 | 48 | ATOMIC_NOTIFIER_HEAD(panic_notifier_list); |
1da177e4 LT |
49 | |
50 | EXPORT_SYMBOL(panic_notifier_list); | |
51 | ||
c7ff0d9c | 52 | static long no_blink(int state) |
8aeee85a | 53 | { |
c7ff0d9c | 54 | return 0; |
8aeee85a AB |
55 | } |
56 | ||
c7ff0d9c TS |
57 | /* Returns how long it waited in ms */ |
58 | long (*panic_blink)(int state); | |
59 | EXPORT_SYMBOL(panic_blink); | |
60 | ||
93e13a36 MH |
61 | /* |
62 | * Stop ourself in panic -- architecture code may override this | |
63 | */ | |
64 | void __weak panic_smp_self_stop(void) | |
65 | { | |
66 | while (1) | |
67 | cpu_relax(); | |
68 | } | |
69 | ||
58c5661f HK |
70 | /* |
71 | * Stop ourselves in NMI context if another CPU has already panicked. Arch code | |
72 | * may override this to prepare for crash dumping, e.g. save regs info. | |
73 | */ | |
74 | void __weak nmi_panic_self_stop(struct pt_regs *regs) | |
75 | { | |
76 | panic_smp_self_stop(); | |
77 | } | |
78 | ||
0ee59413 HK |
79 | /* |
80 | * Stop other CPUs in panic. Architecture dependent code may override this | |
81 | * with more suitable version. For example, if the architecture supports | |
82 | * crash dump, it should save registers of each stopped CPU and disable | |
83 | * per-CPU features such as virtualization extensions. | |
84 | */ | |
85 | void __weak crash_smp_send_stop(void) | |
86 | { | |
87 | static int cpus_stopped; | |
88 | ||
89 | /* | |
90 | * This function can be called twice in panic path, but obviously | |
91 | * we execute this only once. | |
92 | */ | |
93 | if (cpus_stopped) | |
94 | return; | |
95 | ||
96 | /* | |
97 | * Note smp_send_stop is the usual smp shutdown function, which | |
98 | * unfortunately means it may not be hardened to work in a panic | |
99 | * situation. | |
100 | */ | |
101 | smp_send_stop(); | |
102 | cpus_stopped = 1; | |
103 | } | |
104 | ||
1717f209 HK |
105 | atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID); |
106 | ||
ebc41f20 HK |
107 | /* |
108 | * A variant of panic() called from NMI context. We return if we've already | |
109 | * panicked on this CPU. If another CPU already panicked, loop in | |
110 | * nmi_panic_self_stop() which can provide architecture dependent code such | |
111 | * as saving register state for crash dump. | |
112 | */ | |
113 | void nmi_panic(struct pt_regs *regs, const char *msg) | |
114 | { | |
115 | int old_cpu, cpu; | |
116 | ||
117 | cpu = raw_smp_processor_id(); | |
118 | old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); | |
119 | ||
120 | if (old_cpu == PANIC_CPU_INVALID) | |
121 | panic("%s", msg); | |
122 | else if (old_cpu != cpu) | |
123 | nmi_panic_self_stop(regs); | |
124 | } | |
125 | EXPORT_SYMBOL(nmi_panic); | |
126 | ||
1da177e4 LT |
127 | /** |
128 | * panic - halt the system | |
129 | * @fmt: The text string to print | |
130 | * | |
131 | * Display a message, then perform cleanups. | |
132 | * | |
133 | * This function never returns. | |
134 | */ | |
9402c95f | 135 | void panic(const char *fmt, ...) |
1da177e4 | 136 | { |
1da177e4 LT |
137 | static char buf[1024]; |
138 | va_list args; | |
c7ff0d9c TS |
139 | long i, i_next = 0; |
140 | int state = 0; | |
1717f209 | 141 | int old_cpu, this_cpu; |
b26e27dd | 142 | bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers; |
1da177e4 | 143 | |
190320c3 VM |
144 | /* |
145 | * Disable local interrupts. This will prevent panic_smp_self_stop | |
146 | * from deadlocking the first cpu that invokes the panic, since | |
147 | * there is nothing to prevent an interrupt handler (that runs | |
1717f209 | 148 | * after setting panic_cpu) from invoking panic() again. |
190320c3 VM |
149 | */ |
150 | local_irq_disable(); | |
a9ff494d | 151 | preempt_disable_notrace(); |
190320c3 | 152 | |
dc009d92 | 153 | /* |
c95dbf27 IM |
154 | * It's possible to come here directly from a panic-assertion and |
155 | * not have preempt disabled. Some functions called from here want | |
dc009d92 | 156 | * preempt to be disabled. No point enabling it later though... |
93e13a36 MH |
157 | * |
158 | * Only one CPU is allowed to execute the panic code from here. For | |
159 | * multiple parallel invocations of panic, all other CPUs either | |
160 | * stop themself or will wait until they are stopped by the 1st CPU | |
161 | * with smp_send_stop(). | |
1717f209 HK |
162 | * |
163 | * `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which | |
164 | * comes here, so go ahead. | |
165 | * `old_cpu == this_cpu' means we came from nmi_panic() which sets | |
166 | * panic_cpu to this CPU. In this case, this is also the 1st CPU. | |
dc009d92 | 167 | */ |
1717f209 HK |
168 | this_cpu = raw_smp_processor_id(); |
169 | old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu); | |
170 | ||
171 | if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu) | |
93e13a36 | 172 | panic_smp_self_stop(); |
dc009d92 | 173 | |
5b530fc1 | 174 | console_verbose(); |
1da177e4 LT |
175 | bust_spinlocks(1); |
176 | va_start(args, fmt); | |
177 | vsnprintf(buf, sizeof(buf), fmt, args); | |
178 | va_end(args); | |
d7c0847f | 179 | pr_emerg("Kernel panic - not syncing: %s\n", buf); |
5cb27301 | 180 | #ifdef CONFIG_DEBUG_BUGVERBOSE |
6e6f0a1f AK |
181 | /* |
182 | * Avoid nested stack-dumping if a panic occurs during oops processing | |
183 | */ | |
026ee1f6 | 184 | if (!test_taint(TAINT_DIE) && oops_in_progress <= 1) |
6e6f0a1f | 185 | dump_stack(); |
5cb27301 | 186 | #endif |
1da177e4 | 187 | |
dc009d92 EB |
188 | /* |
189 | * If we have crashed and we have a crash kernel loaded let it handle | |
190 | * everything else. | |
f06e5153 MH |
191 | * If we want to run this after calling panic_notifiers, pass |
192 | * the "crash_kexec_post_notifiers" option to the kernel. | |
7bbee5ca HK |
193 | * |
194 | * Bypass the panic_cpu check and call __crash_kexec directly. | |
dc009d92 | 195 | */ |
b26e27dd | 196 | if (!_crash_kexec_post_notifiers) { |
f92bac3b | 197 | printk_safe_flush_on_panic(); |
7bbee5ca | 198 | __crash_kexec(NULL); |
dc009d92 | 199 | |
0ee59413 HK |
200 | /* |
201 | * Note smp_send_stop is the usual smp shutdown function, which | |
202 | * unfortunately means it may not be hardened to work in a | |
203 | * panic situation. | |
204 | */ | |
205 | smp_send_stop(); | |
206 | } else { | |
207 | /* | |
208 | * If we want to do crash dump after notifier calls and | |
209 | * kmsg_dump, we will need architecture dependent extra | |
210 | * works in addition to stopping other CPUs. | |
211 | */ | |
212 | crash_smp_send_stop(); | |
213 | } | |
1da177e4 | 214 | |
6723734c KC |
215 | /* |
216 | * Run any panic handlers, including those that might need to | |
217 | * add information to the kmsg dump output. | |
218 | */ | |
e041c683 | 219 | atomic_notifier_call_chain(&panic_notifier_list, 0, buf); |
1da177e4 | 220 | |
cf9b1106 | 221 | /* Call flush even twice. It tries harder with a single online CPU */ |
f92bac3b | 222 | printk_safe_flush_on_panic(); |
6723734c KC |
223 | kmsg_dump(KMSG_DUMP_PANIC); |
224 | ||
f06e5153 MH |
225 | /* |
226 | * If you doubt kdump always works fine in any situation, | |
227 | * "crash_kexec_post_notifiers" offers you a chance to run | |
228 | * panic_notifiers and dumping kmsg before kdump. | |
229 | * Note: since some panic_notifiers can make crashed kernel | |
230 | * more unstable, it can increase risks of the kdump failure too. | |
7bbee5ca HK |
231 | * |
232 | * Bypass the panic_cpu check and call __crash_kexec directly. | |
f06e5153 | 233 | */ |
b26e27dd | 234 | if (_crash_kexec_post_notifiers) |
7bbee5ca | 235 | __crash_kexec(NULL); |
f06e5153 | 236 | |
f30ffd9b SS |
237 | #ifdef CONFIG_VT |
238 | unblank_screen(); | |
239 | #endif | |
240 | console_unblank(); | |
d014e889 | 241 | |
08d78658 VK |
242 | /* |
243 | * We may have ended up stopping the CPU holding the lock (in | |
244 | * smp_send_stop()) while still having some valuable data in the console | |
245 | * buffer. Try to acquire the lock then release it regardless of the | |
7625b3a0 VK |
246 | * result. The release will also print the buffers out. Locks debug |
247 | * should be disabled to avoid reporting bad unlock balance when | |
248 | * panic() is not being callled from OOPS. | |
08d78658 | 249 | */ |
7625b3a0 | 250 | debug_locks_off(); |
8d91f8b1 | 251 | console_flush_on_panic(); |
08d78658 | 252 | |
c7ff0d9c TS |
253 | if (!panic_blink) |
254 | panic_blink = no_blink; | |
255 | ||
dc009d92 | 256 | if (panic_timeout > 0) { |
1da177e4 | 257 | /* |
c95dbf27 IM |
258 | * Delay timeout seconds before rebooting the machine. |
259 | * We can't use the "normal" timers since we just panicked. | |
260 | */ | |
ff7a28a0 | 261 | pr_emerg("Rebooting in %d seconds..\n", panic_timeout); |
c95dbf27 | 262 | |
c7ff0d9c | 263 | for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) { |
1da177e4 | 264 | touch_nmi_watchdog(); |
c7ff0d9c TS |
265 | if (i >= i_next) { |
266 | i += panic_blink(state ^= 1); | |
267 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
268 | } | |
269 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 | 270 | } |
4302fbc8 HD |
271 | } |
272 | if (panic_timeout != 0) { | |
c95dbf27 IM |
273 | /* |
274 | * This will not be a clean reboot, with everything | |
275 | * shutting down. But if there is a chance of | |
276 | * rebooting the system it will be rebooted. | |
1da177e4 | 277 | */ |
2f048ea8 | 278 | emergency_restart(); |
1da177e4 LT |
279 | } |
280 | #ifdef __sparc__ | |
281 | { | |
282 | extern int stop_a_enabled; | |
a271c241 | 283 | /* Make sure the user can actually press Stop-A (L1-A) */ |
1da177e4 | 284 | stop_a_enabled = 1; |
7db60d05 VK |
285 | pr_emerg("Press Stop-A (L1-A) from sun keyboard or send break\n" |
286 | "twice on console to return to the boot prom\n"); | |
1da177e4 LT |
287 | } |
288 | #endif | |
347a8dc3 | 289 | #if defined(CONFIG_S390) |
c95dbf27 IM |
290 | { |
291 | unsigned long caller; | |
292 | ||
293 | caller = (unsigned long)__builtin_return_address(0); | |
294 | disabled_wait(caller); | |
295 | } | |
1da177e4 | 296 | #endif |
d7c0847f | 297 | pr_emerg("---[ end Kernel panic - not syncing: %s\n", buf); |
1da177e4 | 298 | local_irq_enable(); |
c7ff0d9c | 299 | for (i = 0; ; i += PANIC_TIMER_STEP) { |
c22db941 | 300 | touch_softlockup_watchdog(); |
c7ff0d9c TS |
301 | if (i >= i_next) { |
302 | i += panic_blink(state ^= 1); | |
303 | i_next = i + 3600 / PANIC_BLINK_SPD; | |
304 | } | |
305 | mdelay(PANIC_TIMER_STEP); | |
1da177e4 LT |
306 | } |
307 | } | |
308 | ||
309 | EXPORT_SYMBOL(panic); | |
310 | ||
7fd8329b PM |
311 | /* |
312 | * TAINT_FORCED_RMMOD could be a per-module flag but the module | |
313 | * is being removed anyway. | |
314 | */ | |
315 | const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = { | |
316 | { 'P', 'G', true }, /* TAINT_PROPRIETARY_MODULE */ | |
317 | { 'F', ' ', true }, /* TAINT_FORCED_MODULE */ | |
318 | { 'S', ' ', false }, /* TAINT_CPU_OUT_OF_SPEC */ | |
319 | { 'R', ' ', false }, /* TAINT_FORCED_RMMOD */ | |
320 | { 'M', ' ', false }, /* TAINT_MACHINE_CHECK */ | |
321 | { 'B', ' ', false }, /* TAINT_BAD_PAGE */ | |
322 | { 'U', ' ', false }, /* TAINT_USER */ | |
323 | { 'D', ' ', false }, /* TAINT_DIE */ | |
324 | { 'A', ' ', false }, /* TAINT_OVERRIDDEN_ACPI_TABLE */ | |
325 | { 'W', ' ', false }, /* TAINT_WARN */ | |
326 | { 'C', ' ', true }, /* TAINT_CRAP */ | |
327 | { 'I', ' ', false }, /* TAINT_FIRMWARE_WORKAROUND */ | |
328 | { 'O', ' ', true }, /* TAINT_OOT_MODULE */ | |
329 | { 'E', ' ', true }, /* TAINT_UNSIGNED_MODULE */ | |
330 | { 'L', ' ', false }, /* TAINT_SOFTLOCKUP */ | |
331 | { 'K', ' ', true }, /* TAINT_LIVEPATCH */ | |
4efb442c | 332 | { 'X', ' ', true }, /* TAINT_AUX */ |
25ddbb18 AK |
333 | }; |
334 | ||
1da177e4 LT |
335 | /** |
336 | * print_tainted - return a string to represent the kernel taint state. | |
337 | * | |
338 | * 'P' - Proprietary module has been loaded. | |
339 | * 'F' - Module has been forcibly loaded. | |
340 | * 'S' - SMP with CPUs not designed for SMP. | |
341 | * 'R' - User forced a module unload. | |
9aa5e993 | 342 | * 'M' - System experienced a machine check exception. |
1da177e4 | 343 | * 'B' - System has hit bad_page. |
34f5a398 | 344 | * 'U' - Userspace-defined naughtiness. |
a8005992 | 345 | * 'D' - Kernel has oopsed before |
95b570c9 NH |
346 | * 'A' - ACPI table overridden. |
347 | * 'W' - Taint on warning. | |
061b1bd3 | 348 | * 'C' - modules from drivers/staging are loaded. |
92946bc7 | 349 | * 'I' - Working around severe firmware bug. |
2449b8ba | 350 | * 'O' - Out-of-tree module has been loaded. |
57673c2b | 351 | * 'E' - Unsigned module has been loaded. |
bc53a3f4 | 352 | * 'L' - A soft lockup has previously occurred. |
c5f45465 | 353 | * 'K' - Kernel has been live patched. |
4efb442c | 354 | * 'X' - Auxiliary taint, for distros' use. |
1da177e4 | 355 | * |
fe002a41 | 356 | * The string is overwritten by the next call to print_tainted(). |
1da177e4 | 357 | */ |
1da177e4 LT |
358 | const char *print_tainted(void) |
359 | { | |
7fd8329b | 360 | static char buf[TAINT_FLAGS_COUNT + sizeof("Tainted: ")]; |
25ddbb18 AK |
361 | |
362 | if (tainted_mask) { | |
363 | char *s; | |
364 | int i; | |
365 | ||
366 | s = buf + sprintf(buf, "Tainted: "); | |
7fd8329b PM |
367 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { |
368 | const struct taint_flag *t = &taint_flags[i]; | |
369 | *s++ = test_bit(i, &tainted_mask) ? | |
5eb7c0d0 | 370 | t->c_true : t->c_false; |
25ddbb18 AK |
371 | } |
372 | *s = 0; | |
373 | } else | |
1da177e4 | 374 | snprintf(buf, sizeof(buf), "Not tainted"); |
c95dbf27 IM |
375 | |
376 | return buf; | |
1da177e4 LT |
377 | } |
378 | ||
25ddbb18 | 379 | int test_taint(unsigned flag) |
1da177e4 | 380 | { |
25ddbb18 AK |
381 | return test_bit(flag, &tainted_mask); |
382 | } | |
383 | EXPORT_SYMBOL(test_taint); | |
384 | ||
385 | unsigned long get_taint(void) | |
386 | { | |
387 | return tainted_mask; | |
1da177e4 | 388 | } |
dd287796 | 389 | |
373d4d09 RR |
390 | /** |
391 | * add_taint: add a taint flag if not already set. | |
392 | * @flag: one of the TAINT_* constants. | |
393 | * @lockdep_ok: whether lock debugging is still OK. | |
394 | * | |
395 | * If something bad has gone wrong, you'll want @lockdebug_ok = false, but for | |
396 | * some notewortht-but-not-corrupting cases, it can be set to true. | |
397 | */ | |
398 | void add_taint(unsigned flag, enum lockdep_ok lockdep_ok) | |
dd287796 | 399 | { |
373d4d09 | 400 | if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off()) |
d7c0847f | 401 | pr_warn("Disabling lock debugging due to kernel taint\n"); |
9eeba613 | 402 | |
25ddbb18 | 403 | set_bit(flag, &tainted_mask); |
dd287796 | 404 | } |
1da177e4 | 405 | EXPORT_SYMBOL(add_taint); |
dd287796 AM |
406 | |
407 | static void spin_msec(int msecs) | |
408 | { | |
409 | int i; | |
410 | ||
411 | for (i = 0; i < msecs; i++) { | |
412 | touch_nmi_watchdog(); | |
413 | mdelay(1); | |
414 | } | |
415 | } | |
416 | ||
417 | /* | |
418 | * It just happens that oops_enter() and oops_exit() are identically | |
419 | * implemented... | |
420 | */ | |
421 | static void do_oops_enter_exit(void) | |
422 | { | |
423 | unsigned long flags; | |
424 | static int spin_counter; | |
425 | ||
426 | if (!pause_on_oops) | |
427 | return; | |
428 | ||
429 | spin_lock_irqsave(&pause_on_oops_lock, flags); | |
430 | if (pause_on_oops_flag == 0) { | |
431 | /* This CPU may now print the oops message */ | |
432 | pause_on_oops_flag = 1; | |
433 | } else { | |
434 | /* We need to stall this CPU */ | |
435 | if (!spin_counter) { | |
436 | /* This CPU gets to do the counting */ | |
437 | spin_counter = pause_on_oops; | |
438 | do { | |
439 | spin_unlock(&pause_on_oops_lock); | |
440 | spin_msec(MSEC_PER_SEC); | |
441 | spin_lock(&pause_on_oops_lock); | |
442 | } while (--spin_counter); | |
443 | pause_on_oops_flag = 0; | |
444 | } else { | |
445 | /* This CPU waits for a different one */ | |
446 | while (spin_counter) { | |
447 | spin_unlock(&pause_on_oops_lock); | |
448 | spin_msec(1); | |
449 | spin_lock(&pause_on_oops_lock); | |
450 | } | |
451 | } | |
452 | } | |
453 | spin_unlock_irqrestore(&pause_on_oops_lock, flags); | |
454 | } | |
455 | ||
456 | /* | |
c95dbf27 IM |
457 | * Return true if the calling CPU is allowed to print oops-related info. |
458 | * This is a bit racy.. | |
dd287796 AM |
459 | */ |
460 | int oops_may_print(void) | |
461 | { | |
462 | return pause_on_oops_flag == 0; | |
463 | } | |
464 | ||
465 | /* | |
466 | * Called when the architecture enters its oops handler, before it prints | |
c95dbf27 IM |
467 | * anything. If this is the first CPU to oops, and it's oopsing the first |
468 | * time then let it proceed. | |
dd287796 | 469 | * |
c95dbf27 IM |
470 | * This is all enabled by the pause_on_oops kernel boot option. We do all |
471 | * this to ensure that oopses don't scroll off the screen. It has the | |
472 | * side-effect of preventing later-oopsing CPUs from mucking up the display, | |
473 | * too. | |
dd287796 | 474 | * |
c95dbf27 IM |
475 | * It turns out that the CPU which is allowed to print ends up pausing for |
476 | * the right duration, whereas all the other CPUs pause for twice as long: | |
477 | * once in oops_enter(), once in oops_exit(). | |
dd287796 AM |
478 | */ |
479 | void oops_enter(void) | |
480 | { | |
bdff7870 | 481 | tracing_off(); |
c95dbf27 IM |
482 | /* can't trust the integrity of the kernel anymore: */ |
483 | debug_locks_off(); | |
dd287796 AM |
484 | do_oops_enter_exit(); |
485 | } | |
486 | ||
2c3b20e9 AV |
487 | /* |
488 | * 64-bit random ID for oopses: | |
489 | */ | |
490 | static u64 oops_id; | |
491 | ||
492 | static int init_oops_id(void) | |
493 | { | |
494 | if (!oops_id) | |
495 | get_random_bytes(&oops_id, sizeof(oops_id)); | |
d6624f99 AV |
496 | else |
497 | oops_id++; | |
2c3b20e9 AV |
498 | |
499 | return 0; | |
500 | } | |
501 | late_initcall(init_oops_id); | |
502 | ||
863a6049 | 503 | void print_oops_end_marker(void) |
71c33911 AV |
504 | { |
505 | init_oops_id(); | |
d7c0847f | 506 | pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id); |
71c33911 AV |
507 | } |
508 | ||
dd287796 AM |
509 | /* |
510 | * Called when the architecture exits its oops handler, after printing | |
511 | * everything. | |
512 | */ | |
513 | void oops_exit(void) | |
514 | { | |
515 | do_oops_enter_exit(); | |
71c33911 | 516 | print_oops_end_marker(); |
456b565c | 517 | kmsg_dump(KMSG_DUMP_OOPS); |
dd287796 | 518 | } |
3162f751 | 519 | |
2553b67a | 520 | struct warn_args { |
0f6f49a8 | 521 | const char *fmt; |
a8f18b90 | 522 | va_list args; |
0f6f49a8 | 523 | }; |
bd89bb29 | 524 | |
2553b67a JP |
525 | void __warn(const char *file, int line, void *caller, unsigned taint, |
526 | struct pt_regs *regs, struct warn_args *args) | |
0f6f49a8 | 527 | { |
de7edd31 SRRH |
528 | disable_trace_on_warning(); |
529 | ||
a7bed27a KC |
530 | if (args) |
531 | pr_warn(CUT_HERE); | |
2553b67a JP |
532 | |
533 | if (file) | |
534 | pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n", | |
535 | raw_smp_processor_id(), current->pid, file, line, | |
536 | caller); | |
537 | else | |
538 | pr_warn("WARNING: CPU: %d PID: %d at %pS\n", | |
539 | raw_smp_processor_id(), current->pid, caller); | |
74853dba | 540 | |
0f6f49a8 LT |
541 | if (args) |
542 | vprintk(args->fmt, args->args); | |
a8f18b90 | 543 | |
9e3961a0 PB |
544 | if (panic_on_warn) { |
545 | /* | |
546 | * This thread may hit another WARN() in the panic path. | |
547 | * Resetting this prevents additional WARN() from panicking the | |
548 | * system on this thread. Other threads are blocked by the | |
549 | * panic_mutex in panic(). | |
550 | */ | |
551 | panic_on_warn = 0; | |
552 | panic("panic_on_warn set ...\n"); | |
553 | } | |
554 | ||
a8f18b90 | 555 | print_modules(); |
2553b67a JP |
556 | |
557 | if (regs) | |
558 | show_regs(regs); | |
559 | else | |
560 | dump_stack(); | |
561 | ||
a8f18b90 | 562 | print_oops_end_marker(); |
2553b67a | 563 | |
373d4d09 RR |
564 | /* Just a warning, don't kill lockdep. */ |
565 | add_taint(taint, LOCKDEP_STILL_OK); | |
a8f18b90 | 566 | } |
0f6f49a8 | 567 | |
2553b67a | 568 | #ifdef WANT_WARN_ON_SLOWPATH |
0f6f49a8 LT |
569 | void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) |
570 | { | |
2553b67a | 571 | struct warn_args args; |
0f6f49a8 LT |
572 | |
573 | args.fmt = fmt; | |
574 | va_start(args.args, fmt); | |
2553b67a JP |
575 | __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL, |
576 | &args); | |
0f6f49a8 LT |
577 | va_end(args.args); |
578 | } | |
57adc4d2 AK |
579 | EXPORT_SYMBOL(warn_slowpath_fmt); |
580 | ||
b2be0527 BH |
581 | void warn_slowpath_fmt_taint(const char *file, int line, |
582 | unsigned taint, const char *fmt, ...) | |
583 | { | |
2553b67a | 584 | struct warn_args args; |
b2be0527 BH |
585 | |
586 | args.fmt = fmt; | |
587 | va_start(args.args, fmt); | |
2553b67a | 588 | __warn(file, line, __builtin_return_address(0), taint, NULL, &args); |
b2be0527 BH |
589 | va_end(args.args); |
590 | } | |
591 | EXPORT_SYMBOL(warn_slowpath_fmt_taint); | |
592 | ||
57adc4d2 AK |
593 | void warn_slowpath_null(const char *file, int line) |
594 | { | |
a7bed27a | 595 | pr_warn(CUT_HERE); |
2553b67a | 596 | __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL, NULL); |
57adc4d2 AK |
597 | } |
598 | EXPORT_SYMBOL(warn_slowpath_null); | |
a7bed27a KC |
599 | #else |
600 | void __warn_printk(const char *fmt, ...) | |
601 | { | |
602 | va_list args; | |
603 | ||
604 | pr_warn(CUT_HERE); | |
605 | ||
606 | va_start(args, fmt); | |
607 | vprintk(fmt, args); | |
608 | va_end(args); | |
609 | } | |
610 | EXPORT_SYMBOL(__warn_printk); | |
79b4cc5e AV |
611 | #endif |
612 | ||
b1fca27d AK |
613 | #ifdef CONFIG_BUG |
614 | ||
615 | /* Support resetting WARN*_ONCE state */ | |
616 | ||
617 | static int clear_warn_once_set(void *data, u64 val) | |
618 | { | |
aaf5dcfb | 619 | generic_bug_clear_once(); |
b1fca27d AK |
620 | memset(__start_once, 0, __end_once - __start_once); |
621 | return 0; | |
622 | } | |
623 | ||
624 | DEFINE_SIMPLE_ATTRIBUTE(clear_warn_once_fops, | |
625 | NULL, | |
626 | clear_warn_once_set, | |
627 | "%lld\n"); | |
628 | ||
629 | static __init int register_warn_debugfs(void) | |
630 | { | |
631 | /* Don't care about failure */ | |
aaf5dcfb | 632 | debugfs_create_file("clear_warn_once", 0200, NULL, |
b1fca27d AK |
633 | NULL, &clear_warn_once_fops); |
634 | return 0; | |
635 | } | |
636 | ||
637 | device_initcall(register_warn_debugfs); | |
638 | #endif | |
639 | ||
3162f751 | 640 | #ifdef CONFIG_CC_STACKPROTECTOR |
54371a43 | 641 | |
3162f751 AV |
642 | /* |
643 | * Called when gcc's -fstack-protector feature is used, and | |
644 | * gcc detects corruption of the on-stack canary value | |
645 | */ | |
a7330c99 | 646 | __visible void __stack_chk_fail(void) |
3162f751 | 647 | { |
91e786b9 | 648 | panic("stack-protector: Kernel stack is corrupted in: %pB", |
517a92c4 | 649 | __builtin_return_address(0)); |
3162f751 AV |
650 | } |
651 | EXPORT_SYMBOL(__stack_chk_fail); | |
54371a43 | 652 | |
3162f751 | 653 | #endif |
f44dd164 | 654 | |
7a46ec0e KC |
655 | #ifdef CONFIG_ARCH_HAS_REFCOUNT |
656 | void refcount_error_report(struct pt_regs *regs, const char *err) | |
657 | { | |
658 | WARN_RATELIMIT(1, "refcount_t %s at %pB in %s[%d], uid/euid: %u/%u\n", | |
659 | err, (void *)instruction_pointer(regs), | |
660 | current->comm, task_pid_nr(current), | |
661 | from_kuid_munged(&init_user_ns, current_uid()), | |
662 | from_kuid_munged(&init_user_ns, current_euid())); | |
663 | } | |
664 | #endif | |
665 | ||
f44dd164 RR |
666 | core_param(panic, panic_timeout, int, 0644); |
667 | core_param(pause_on_oops, pause_on_oops, int, 0644); | |
9e3961a0 | 668 | core_param(panic_on_warn, panic_on_warn, int, 0644); |
b26e27dd | 669 | core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644); |
f06e5153 | 670 | |
d404ab0a OH |
671 | static int __init oops_setup(char *s) |
672 | { | |
673 | if (!s) | |
674 | return -EINVAL; | |
675 | if (!strcmp(s, "panic")) | |
676 | panic_on_oops = 1; | |
677 | return 0; | |
678 | } | |
679 | early_param("oops", oops_setup); |