projects/linux·blob v2.6.12-rc5 · refs

157 lines · 3.4 KiB

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>
21
22int panic_timeout;
23int panic_on_oops;
24int tainted;
25
26EXPORT_SYMBOL(panic_timeout);
27
28struct notifier_block *panic_notifier_list;
29
30EXPORT_SYMBOL(panic_notifier_list);
31
32static int __init panic_setup(char *str)
33{
34 panic_timeout = simple_strtoul(str, NULL, 0);
35 return 1;
36}
37__setup("panic=", panic_setup);
38
39static long no_blink(long time)
40{
41 return 0;
42}
43
44/* Returns how long it waited in ms */
45long (*panic_blink)(long time);
46EXPORT_SYMBOL(panic_blink);
47
48/**
49 * panic - halt the system
50 * @fmt: The text string to print
51 *
52 * Display a message, then perform cleanups.
53 *
54 * This function never returns.
55 */
56
57NORET_TYPE void panic(const char * fmt, ...)
58{
59 long i;
60 static char buf[1024];
61 va_list args;
62#if defined(CONFIG_ARCH_S390)
63 unsigned long caller = (unsigned long) __builtin_return_address(0);
64#endif
65
66 bust_spinlocks(1);
67 va_start(args, fmt);
68 vsnprintf(buf, sizeof(buf), fmt, args);
69 va_end(args);
70 printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
71 bust_spinlocks(0);
72
73#ifdef CONFIG_SMP
74 smp_send_stop();
75#endif
76
77 notifier_call_chain(&panic_notifier_list, 0, buf);
78
79 if (!panic_blink)
80 panic_blink = no_blink;
81
82 if (panic_timeout > 0)
83 {
84 /*
85 * Delay timeout seconds before rebooting the machine.
86 * We can't use the "normal" timers since we just panicked..
87 */
88 printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
89 for (i = 0; i < panic_timeout*1000; ) {
90 touch_nmi_watchdog();
91 i += panic_blink(i);
92 mdelay(1);
93 i++;
94 }
95 /*
96 * Should we run the reboot notifier. For the moment Im
97 * choosing not too. It might crash, be corrupt or do
98 * more harm than good for other reasons.
99 */
100 machine_restart(NULL);
101 }
102#ifdef __sparc__
103 {
104 extern int stop_a_enabled;
105 /* Make sure the user can actually press Stop-A (L1-A) */
106 stop_a_enabled = 1;
107 printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n");
108 }
109#endif
110#if defined(CONFIG_ARCH_S390)
111 disabled_wait(caller);
112#endif
113 local_irq_enable();
114 for (i = 0;;) {
115 i += panic_blink(i);
116 mdelay(1);
117 i++;
118 }
119}
120
121EXPORT_SYMBOL(panic);
122
123/**
124 * print_tainted - return a string to represent the kernel taint state.
125 *
126 * 'P' - Proprietary module has been loaded.
127 * 'F' - Module has been forcibly loaded.
128 * 'S' - SMP with CPUs not designed for SMP.
129 * 'R' - User forced a module unload.
130 * 'M' - Machine had a machine check experience.
131 * 'B' - System has hit bad_page.
132 *
133 * The string is overwritten by the next call to print_taint().
134 */
135
136const char *print_tainted(void)
137{
138 static char buf[20];
139 if (tainted) {
140 snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c",
141 tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G',
142 tainted & TAINT_FORCED_MODULE ? 'F' : ' ',
143 tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
144 tainted & TAINT_FORCED_RMMOD ? 'R' : ' ',
145 tainted & TAINT_MACHINE_CHECK ? 'M' : ' ',
146 tainted & TAINT_BAD_PAGE ? 'B' : ' ');
147 }
148 else
149 snprintf(buf, sizeof(buf), "Not tainted");
150 return(buf);
151}
152
153void add_taint(unsigned flag)
154{
155 tainted |= flag;
156}
157EXPORT_SYMBOL(add_taint);