kernel/panic.c

   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 <stdarg.h>
  12
  13 #include <linux/kernel.h>
  14 #include <linux/sched.h>
  15 #include <linux/delay.h>
  16 #include <linux/smp.h>
  17 #include <linux/reboot.h>
  18 #include <linux/init.h>
  19 #include <linux/sysrq.h>
  20 #include <linux/interrupt.h>
  21
  22 asmlinkage void sys_sync(void); /* it's really int */
  23 extern void unblank_console(void);
  24 extern int C_A_D;
  25
  26 int panic_timeout = 0;
  27
  28 void __init panic_setup(char *str, int *ints)
  29 {
  30         if (ints[0] == 1)
  31                 panic_timeout = ints[1];
  32 }
  33
  34 NORET_TYPE void panic(const char * fmt, ...)
  35 {
  36         static char buf[1024];
  37         va_list args;
  38
  39         va_start(args, fmt);
  40         vsprintf(buf, fmt, args);
  41         va_end(args);
  42         printk(KERN_EMERG "Kernel panic: %s\n",buf);
  43         if (current == task[0])
  44                 printk(KERN_EMERG "In swapper task - not syncing\n");
  45         else if (in_interrupt())
  46                 printk(KERN_EMERG "In interrupt handler - not syncing\n");
  47         else
  48                 sys_sync();
  49
  50         unblank_console();
  51
  52 #ifdef __SMP__
  53         smp_message_pass(MSG_ALL_BUT_SELF, MSG_STOP_CPU, 0, 0);
  54 #endif
  55         if (panic_timeout > 0)
  56         {
  57                 /*
  58                  * Delay timeout seconds before rebooting the machine.
  59                  * We can't use the "normal" timers since we just panicked..
  60                  */
  61                 printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
  62                 mdelay(panic_timeout*1000);
  63                 /*
  64                  *      Should we run the reboot notifier. For the moment Im
  65                  *      choosing not too. It might crash, be corrupt or do
  66                  *      more harm than good for other reasons.
  67                  */
  68                 machine_restart(NULL);
  69         }
  70 #ifdef __sparc__
  71         printk("Press L1-A to return to the boot prom\n");
  72 #endif
  73         sti();
  74         for(;;) {
  75                 CHECK_EMERGENCY_SYNC
  76         }
  77 }
  78