Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
| 11 | #include <linux/config.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/sched.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/reboot.h> |
| 16 | #include <linux/notifier.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/sysrq.h> |
| 19 | #include <linux/interrupt.h> |
| 20 | #include <linux/nmi.h> |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 21 | #include <linux/kexec.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | int panic_timeout; |
| 24 | int panic_on_oops; |
| 25 | int tainted; |
| 26 | |
| 27 | EXPORT_SYMBOL(panic_timeout); |
| 28 | |
| 29 | struct notifier_block *panic_notifier_list; |
| 30 | |
| 31 | EXPORT_SYMBOL(panic_notifier_list); |
| 32 | |
| 33 | static int __init panic_setup(char *str) |
| 34 | { |
| 35 | panic_timeout = simple_strtoul(str, NULL, 0); |
| 36 | return 1; |
| 37 | } |
| 38 | __setup("panic=", panic_setup); |
| 39 | |
| 40 | static long no_blink(long time) |
| 41 | { |
| 42 | return 0; |
| 43 | } |
| 44 | |
| 45 | /* Returns how long it waited in ms */ |
| 46 | long (*panic_blink)(long time); |
| 47 | EXPORT_SYMBOL(panic_blink); |
| 48 | |
| 49 | /** |
| 50 | * panic - halt the system |
| 51 | * @fmt: The text string to print |
| 52 | * |
| 53 | * Display a message, then perform cleanups. |
| 54 | * |
| 55 | * This function never returns. |
| 56 | */ |
| 57 | |
| 58 | NORET_TYPE void panic(const char * fmt, ...) |
| 59 | { |
| 60 | long i; |
| 61 | static char buf[1024]; |
| 62 | va_list args; |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 63 | #if defined(CONFIG_S390) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | unsigned long caller = (unsigned long) __builtin_return_address(0); |
| 65 | #endif |
| 66 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 67 | /* |
| 68 | * It's possible to come here directly from a panic-assertion and not |
| 69 | * have preempt disabled. Some functions called from here want |
| 70 | * preempt to be disabled. No point enabling it later though... |
| 71 | */ |
| 72 | preempt_disable(); |
| 73 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | bust_spinlocks(1); |
| 75 | va_start(args, fmt); |
| 76 | vsnprintf(buf, sizeof(buf), fmt, args); |
| 77 | va_end(args); |
| 78 | printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf); |
| 79 | bust_spinlocks(0); |
| 80 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 81 | /* |
| 82 | * If we have crashed and we have a crash kernel loaded let it handle |
| 83 | * everything else. |
| 84 | * Do we want to call this before we try to display a message? |
| 85 | */ |
Alexander Nyberg | 6e274d1 | 2005-06-25 14:58:26 -0700 | [diff] [blame] | 86 | crash_kexec(NULL); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 87 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | #ifdef CONFIG_SMP |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 89 | /* |
| 90 | * Note smp_send_stop is the usual smp shutdown function, which |
| 91 | * unfortunately means it may not be hardened to work in a panic |
| 92 | * situation. |
| 93 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | smp_send_stop(); |
| 95 | #endif |
| 96 | |
| 97 | notifier_call_chain(&panic_notifier_list, 0, buf); |
| 98 | |
| 99 | if (!panic_blink) |
| 100 | panic_blink = no_blink; |
| 101 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 102 | if (panic_timeout > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | /* |
| 104 | * Delay timeout seconds before rebooting the machine. |
| 105 | * We can't use the "normal" timers since we just panicked.. |
| 106 | */ |
| 107 | printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout); |
| 108 | for (i = 0; i < panic_timeout*1000; ) { |
| 109 | touch_nmi_watchdog(); |
| 110 | i += panic_blink(i); |
| 111 | mdelay(1); |
| 112 | i++; |
| 113 | } |
Eric W. Biederman | 2f048ea | 2005-07-26 11:49:23 -0600 | [diff] [blame] | 114 | /* This will not be a clean reboot, with everything |
| 115 | * shutting down. But if there is a chance of |
| 116 | * rebooting the system it will be rebooted. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | */ |
Eric W. Biederman | 2f048ea | 2005-07-26 11:49:23 -0600 | [diff] [blame] | 118 | emergency_restart(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | } |
| 120 | #ifdef __sparc__ |
| 121 | { |
| 122 | extern int stop_a_enabled; |
Tom 'spot' Callaway | a271c24 | 2005-04-24 20:38:02 -0700 | [diff] [blame] | 123 | /* Make sure the user can actually press Stop-A (L1-A) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | stop_a_enabled = 1; |
Tom 'spot' Callaway | a271c24 | 2005-04-24 20:38:02 -0700 | [diff] [blame] | 125 | printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | } |
| 127 | #endif |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 128 | #if defined(CONFIG_S390) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | disabled_wait(caller); |
| 130 | #endif |
| 131 | local_irq_enable(); |
| 132 | for (i = 0;;) { |
| 133 | i += panic_blink(i); |
| 134 | mdelay(1); |
| 135 | i++; |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | EXPORT_SYMBOL(panic); |
| 140 | |
| 141 | /** |
| 142 | * print_tainted - return a string to represent the kernel taint state. |
| 143 | * |
| 144 | * 'P' - Proprietary module has been loaded. |
| 145 | * 'F' - Module has been forcibly loaded. |
| 146 | * 'S' - SMP with CPUs not designed for SMP. |
| 147 | * 'R' - User forced a module unload. |
| 148 | * 'M' - Machine had a machine check experience. |
| 149 | * 'B' - System has hit bad_page. |
| 150 | * |
| 151 | * The string is overwritten by the next call to print_taint(). |
| 152 | */ |
| 153 | |
| 154 | const char *print_tainted(void) |
| 155 | { |
| 156 | static char buf[20]; |
| 157 | if (tainted) { |
| 158 | snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c", |
| 159 | tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G', |
| 160 | tainted & TAINT_FORCED_MODULE ? 'F' : ' ', |
| 161 | tainted & TAINT_UNSAFE_SMP ? 'S' : ' ', |
| 162 | tainted & TAINT_FORCED_RMMOD ? 'R' : ' ', |
| 163 | tainted & TAINT_MACHINE_CHECK ? 'M' : ' ', |
| 164 | tainted & TAINT_BAD_PAGE ? 'B' : ' '); |
| 165 | } |
| 166 | else |
| 167 | snprintf(buf, sizeof(buf), "Not tainted"); |
| 168 | return(buf); |
| 169 | } |
| 170 | |
| 171 | void add_taint(unsigned flag) |
| 172 | { |
| 173 | tainted |= flag; |
| 174 | } |
| 175 | EXPORT_SYMBOL(add_taint); |