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/*
* linux/kernel/panic.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/*
* This function is used through-out the kernel (including mm and fs)
* to indicate a major problem.
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/sysrq.h>
#include <linux/interrupt.h>
#include <linux/nmi.h>
#include <linux/kexec.h>
int panic_timeout;
int panic_on_oops;
int tainted;
EXPORT_SYMBOL(panic_timeout);
struct notifier_block *panic_notifier_list;
EXPORT_SYMBOL(panic_notifier_list);
static int __init panic_setup(char *str)
{
panic_timeout = simple_strtoul(str, NULL, 0);
return 1;
}
__setup("panic=", panic_setup);
static long no_blink(long time)
{
return 0;
}
/* Returns how long it waited in ms */
long (*panic_blink)(long time);
EXPORT_SYMBOL(panic_blink);
/**
* panic - halt the system
* @fmt: The text string to print
*
* Display a message, then perform cleanups.
*
* This function never returns.
*/
NORET_TYPE void panic(const char * fmt, ...)
{
long i;
static char buf[1024];
va_list args;
#if defined(CONFIG_S390)
unsigned long caller = (unsigned long) __builtin_return_address(0);
#endif
/*
* It's possible to come here directly from a panic-assertion and not
* have preempt disabled. Some functions called from here want
* preempt to be disabled. No point enabling it later though...
*/
preempt_disable();
bust_spinlocks(1);
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
bust_spinlocks(0);
/*
* If we have crashed and we have a crash kernel loaded let it handle
* everything else.
* Do we want to call this before we try to display a message?
*/
crash_kexec(NULL);
#ifdef CONFIG_SMP
/*
* Note smp_send_stop is the usual smp shutdown function, which
* unfortunately means it may not be hardened to work in a panic
* situation.
*/
smp_send_stop();
#endif
notifier_call_chain(&panic_notifier_list, 0, buf);
if (!panic_blink)
panic_blink = no_blink;
if (panic_timeout > 0) {
/*
* Delay timeout seconds before rebooting the machine.
* We can't use the "normal" timers since we just panicked..
*/
printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
for (i = 0; i < panic_timeout*1000; ) {
touch_nmi_watchdog();
i += panic_blink(i);
mdelay(1);
i++;
}
/* This will not be a clean reboot, with everything
* shutting down. But if there is a chance of
* rebooting the system it will be rebooted.
*/
emergency_restart();
}
#ifdef __sparc__
{
extern int stop_a_enabled;
/* Make sure the user can actually press Stop-A (L1-A) */
stop_a_enabled = 1;
printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n");
}
#endif
#if defined(CONFIG_S390)
disabled_wait(caller);
#endif
local_irq_enable();
for (i = 0;;) {
i += panic_blink(i);
mdelay(1);
i++;
}
}
EXPORT_SYMBOL(panic);
/**
* print_tainted - return a string to represent the kernel taint state.
*
* 'P' - Proprietary module has been loaded.
* 'F' - Module has been forcibly loaded.
* 'S' - SMP with CPUs not designed for SMP.
* 'R' - User forced a module unload.
* 'M' - Machine had a machine check experience.
* 'B' - System has hit bad_page.
*
* The string is overwritten by the next call to print_taint().
*/
const char *print_tainted(void)
{
static char buf[20];
if (tainted) {
snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c",
tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G',
tainted & TAINT_FORCED_MODULE ? 'F' : ' ',
tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
tainted & TAINT_FORCED_RMMOD ? 'R' : ' ',
tainted & TAINT_MACHINE_CHECK ? 'M' : ' ',
tainted & TAINT_BAD_PAGE ? 'B' : ' ');
}
else
snprintf(buf, sizeof(buf), "Not tainted");
return(buf);
}
void add_taint(unsigned flag)
{
tainted |= flag;
}
EXPORT_SYMBOL(add_taint);
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