path: root/arch/powerpc/kernel/traps.c

/*
 *  Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 *  Modified by Cort Dougan (cort@cs.nmt.edu)
 *  and Paul Mackerras (paulus@samba.org)
 */

/*
 * This file handles the architecture-dependent parts of hardware exceptions
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/prctl.h>
#include <linux/delay.h>
#include <linux/kprobes.h>
#include <linux/kexec.h>
#include <linux/backlight.h>
#include <linux/bug.h>

#include <asm/kdebug.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/rtas.h>
#include <asm/pmc.h>
#ifdef CONFIG_PPC32
#include <asm/reg.h>
#endif
#ifdef CONFIG_PMAC_BACKLIGHT
#include <asm/backlight.h>
#endif
#ifdef CONFIG_PPC64
#include <asm/firmware.h>
#include <asm/processor.h>
#endif
#include <asm/kexec.h>

#ifdef CONFIG_DEBUGGER
int (*__debugger)(struct pt_regs *regs);
int (*__debugger_ipi)(struct pt_regs *regs);
int (*__debugger_bpt)(struct pt_regs *regs);
int (*__debugger_sstep)(struct pt_regs *regs);
int (*__debugger_iabr_match)(struct pt_regs *regs);
int (*__debugger_dabr_match)(struct pt_regs *regs);
int (*__debugger_fault_handler)(struct pt_regs *regs);

EXPORT_SYMBOL(__debugger);
EXPORT_SYMBOL(__debugger_ipi);
EXPORT_SYMBOL(__debugger_bpt);
EXPORT_SYMBOL(__debugger_sstep);
EXPORT_SYMBOL(__debugger_iabr_match);
EXPORT_SYMBOL(__debugger_dabr_match);
EXPORT_SYMBOL(__debugger_fault_handler);
#endif

ATOMIC_NOTIFIER_HEAD(powerpc_die_chain);

int register_die_notifier(struct notifier_block *nb)
{
	return atomic_notifier_chain_register(&powerpc_die_chain, nb);
}
EXPORT_SYMBOL(register_die_notifier);

int unregister_die_notifier(struct notifier_block *nb)
{
	return atomic_notifier_chain_unregister(&powerpc_die_chain, nb);
}
EXPORT_SYMBOL(unregister_die_notifier);

/*
 * Trap & Exception support
 */

static DEFINE_SPINLOCK(die_lock);

int die(const char *str, struct pt_regs *regs, long err)
{
	static int die_counter;

	if (debugger(regs))
		return 1;

	console_verbose();
	spin_lock_irq(&die_lock);
	bust_spinlocks(1);
#ifdef CONFIG_PMAC_BACKLIGHT
	mutex_lock(&pmac_backlight_mutex);
	if (machine_is(powermac) && pmac_backlight) {
		struct backlight_properties *props;

		props = &pmac_backlight->props;
		props->brightness = props->max_brightness;
		props->power = FB_BLANK_UNBLANK;
		backlight_update_status(pmac_backlight);
	}
	mutex_unlock(&pmac_backlight_mutex);
#endif
	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
#ifdef CONFIG_PREEMPT
	printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
	printk("SMP NR_CPUS=%d ", NR_CPUS);
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
	printk("DEBUG_PAGEALLOC ");
#endif
#ifdef CONFIG_NUMA
	printk("NUMA ");
#endif
	printk("%s\n", ppc_md.name ? "" : ppc_md.name);

	print_modules();
	show_regs(regs);
	bust_spinlocks(0);
	spin_unlock_irq(&die_lock);

	if (kexec_should_crash(current) ||
		kexec_sr_activated(smp_processor_id()))
		crash_kexec(regs);
	crash_kexec_secondary(regs);

	if (in_interrupt())
		panic("Fatal exception in interrupt");

	if (panic_on_oops)
		panic("Fatal exception");

	do_exit(err);

	return 0;
}

void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
{
	siginfo_t info;

	if (!user_mode(regs)) {
		if (die("Exception in kernel mode", regs, signr))
			retu