i386: move kernel

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1250 insertions, 0 deletions

diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
new file mode 100644
index 00000000000..47b0bef335b
--- /dev/null
+++ b/arch/x86/kernel/traps_32.c
@@ -0,0 +1,1250 @@
+/*
+ *  linux/arch/i386/traps.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  Pentium III FXSR, SSE support
+ *	Gareth Hughes <gareth@valinux.com>, May 2000
+ */
+
+/*
+ * 'Traps.c' handles hardware traps and faults after we have saved some
+ * state in 'asm.s'.
+ */
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/highmem.h>
+#include <linux/kallsyms.h>
+#include <linux/ptrace.h>
+#include <linux/utsname.h>
+#include <linux/kprobes.h>
+#include <linux/kexec.h>
+#include <linux/unwind.h>
+#include <linux/uaccess.h>
+#include <linux/nmi.h>
+#include <linux/bug.h>
+
+#ifdef CONFIG_EISA
+#include <linux/ioport.h>
+#include <linux/eisa.h>
+#endif
+
+#ifdef CONFIG_MCA
+#include <linux/mca.h>
+#endif
+
+#if defined(CONFIG_EDAC)
+#include <linux/edac.h>
+#endif
+
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/atomic.h>
+#include <asm/debugreg.h>
+#include <asm/desc.h>
+#include <asm/i387.h>
+#include <asm/nmi.h>
+#include <asm/unwind.h>
+#include <asm/smp.h>
+#include <asm/arch_hooks.h>
+#include <linux/kdebug.h>
+#include <asm/stacktrace.h>
+
+#include <linux/module.h>
+
+#include "mach_traps.h"
+
+int panic_on_unrecovered_nmi;
+
+asmlinkage int system_call(void);
+
+/* Do we ignore FPU interrupts ? */
+char ignore_fpu_irq = 0;
+
+/*
+ * The IDT has to be page-aligned to simplify the Pentium
+ * F0 0F bug workaround.. We have a special link segment
+ * for this.
+ */
+struct desc_struct idt_table[256] __attribute__((__section__(".data.idt"))) = { {0, 0}, };
+
+asmlinkage void divide_error(void);
+asmlinkage void debug(void);
+asmlinkage void nmi(void);
+asmlinkage void int3(void);
+asmlinkage void overflow(void);
+asmlinkage void bounds(void);
+asmlinkage void invalid_op(void);
+asmlinkage void device_not_available(void);
+asmlinkage void coprocessor_segment_overrun(void);
+asmlinkage void invalid_TSS(void);
+asmlinkage void segment_not_present(void);
+asmlinkage void stack_segment(void);
+asmlinkage void general_protection(void);
+asmlinkage void page_fault(void);
+asmlinkage void coprocessor_error(void);
+asmlinkage void simd_coprocessor_error(void);
+asmlinkage void alignment_check(void);
+asmlinkage void spurious_interrupt_bug(void);
+asmlinkage void machine_check(void);
+
+int kstack_depth_to_print = 24;
+static unsigned int code_bytes = 64;
+
+static inline int valid_stack_ptr(struct thread_info *tinfo, void *p, unsigned size)
+{
+	return	p > (void *)tinfo &&
+		p <= (void *)tinfo + THREAD_SIZE - size;
+}
+
+/* The form of the top of the frame on the stack */
+struct stack_frame {
+	struct stack_frame *next_frame;
+	unsigned long return_address;
+};
+
+static inline unsigned long print_context_stack(struct thread_info *tinfo,
+				unsigned long *stack, unsigned long ebp,
+				struct stacktrace_ops *ops, void *data)
+{
+#ifdef	CONFIG_FRAME_POINTER
+	struct stack_frame *frame = (struct stack_frame *)ebp;
+	while (valid_stack_ptr(tinfo, frame, sizeof(*frame))) {
+		struct stack_frame *next;
+		unsigned long addr;
+
+		addr = frame->return_address;
+		ops->address(data, addr);
+		/*
+		 * break out of recursive entries (such as
+		 * end_of_stack_stop_unwind_function). Also,
+		 * we can never allow a frame pointer to
+		 * move downwards!
+		 */
+		next = frame->next_frame;
+		if (next <= frame)
+			break;
+		frame = next;
+	}
+#else
+	while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
+		unsigned long addr;
+
+		addr = *stack++;
+		if (__kernel_text_address(addr))
+			ops->address(data, addr);
+	}
+#endif
+	return ebp;
+}
+
+#define MSG(msg) ops->warning(data, msg)
+
+void dump_trace(struct task_struct *task, struct pt_regs *regs,
+	        unsigned long *stack,
+		struct stacktrace_ops *ops, void *data)
+{
+	unsigned long ebp = 0;
+
+	if (!task)
+		task = current;
+
+	if (!stack) {
+		unsigned long dummy;
+		stack = &dummy;
+		if (task != current)
+			stack = (unsigned long *)task->thread.esp;
+	}
+
+#ifdef CONFIG_FRAME_POINTER
+	if (!ebp) {
+		if (task == current) {
+			/* Grab ebp right from our regs */
+			asm ("movl %%ebp, %0" : "=r" (ebp) : );
+		} else {
+			/* ebp is the last reg pushed by switch_to */
+			ebp = *(unsigned long *) task->thread.esp;
+		}
+	}
+#endif
+
+	while (1) {
+		struct thread_info *context;
+		context = (struct thread_info *)
+			((unsigned long)stack & (~(THREAD_SIZE - 1)));
+		ebp = print_context_stack(context, stack, ebp, ops, data);
+		/* Should be after the line below, but somewhere
+		   in early boot context comes out corrupted and we
+		   can't reference it -AK */
+		if (ops->stack(data, "IRQ") < 0)
+			break;
+		stack = (unsigned long*)context->previous_esp;
+		if (!stack)
+			break;
+		touch_nmi_watchdog();
+	}
+}
+EXPORT_SYMBOL(dump_trace);
+
+static void
+print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
+{
+	printk(data);
+	print_symbol(msg, symbol);
+	printk("\n");
+}
+
+static void print_trace_warning(void *data, char *msg)
+{
+	printk("%s%s\n", (char *)data, msg);
+}
+
+static int print_trace_stack(void *data, char *name)
+{
+	return 0;
+}
+
+/*
+ * Print one address/symbol entries per line.
+ */
+static void print_trace_address(void *data, unsigned long addr)
+{
+	printk("%s [<%08lx>] ", (char *)data, addr);
+	print_symbol("%s\n", addr);
+	touch_nmi_watchdog();
+}
+
+static struct stacktrace_ops print_trace_ops = {
+	.warning = print_trace_warning,
+	.warning_symbol = print_trace_warning_symbol,
+	.stack = print_trace_stack,
+	.address = print_trace_address,
+};
+
+static void
+show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
+		   unsigned long * stack, char *log_lvl)
+{
+	dump_trace(task, regs, stack, &print_trace_ops, log_lvl);
+	printk("%s =======================\n", log_lvl);
+}
+
+void show_trace(struct task_struct *task, struct pt_regs *regs,
+		unsigned long * stack)
+{
+	show_trace_log_lvl(task, regs, stack, "");
+}
+
+static void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+			       unsigned long *esp, char *log_lvl)
+{
+	unsigned long *stack;
+	int i;
+
+	if (esp == NULL) {
+		if (task)
+			esp = (unsigned long*)task->thread.esp;
+		else
+			esp = (unsigned long *)&esp;
+	}
+
+	stack = esp;
+	for(i = 0; i < kstack_depth_to_print; i++) {
+		if (kstack_end(stack))
+			break;
+		if (i && ((i % 8) == 0))
+			printk("\n%s       ", log_lvl);
+		printk("%08lx ", *stack++);
+	}
+	printk("\n%sCall Trace:\n", log_lvl);
+	show_trace_log_lvl(task, regs, esp, log_lvl);
+}
+
+void show_stack(struct task_struct *task, unsigned long *esp)
+{
+	printk("       ");
+	show_stack_log_lvl(task, NULL, esp, "");
+}
+
+/*
+ * The architecture-independent dump_stack generator
+ */
+void dump_stack(void)
+{
+	unsigned long stack;
+
+	show_trace(current, NULL, &stack);
+}
+
+EXPORT_SYMBOL(dump_stack);
+
+void show_registers(struct pt_regs *regs)
+{
+	int i;
+	int in_kernel = 1;
+	unsigned long esp;
+	unsigned short ss, gs;
+
+	esp = (unsigned long) (&regs->esp);
+	savesegment(ss, ss);
+	savesegment(gs, gs);
+	if (user_mode_vm(regs)) {
+		in_kernel = 0;
+		esp = regs->esp;
+		ss = regs->xss & 0xffff;
+	}
+	print_modules();
+	printk(KERN_EMERG "CPU:    %d\n"
+		KERN_EMERG "EIP:    %04x:[<%08lx>]    %s VLI\n"
+		KERN_EMERG "EFLAGS: %08lx   (%s %.*s)\n",
+		smp_processor_id(), 0xffff & regs->xcs, regs->eip,
+		print_tainted(), regs->eflags, init_utsname()->release,
+		(int)strcspn(init_utsname()->version, " "),
+		init_utsname()->version);
+	print_symbol(KERN_EMERG "EIP is at %s\n", regs->eip);
+	printk(KERN_EMERG "eax: %08lx   ebx: %08lx   ecx: %08lx   edx: %08lx\n",
+		regs->eax, regs->ebx, regs->ecx, regs->edx);
+	printk(KERN_EMERG "esi: %08lx   edi: %08lx   ebp: %08lx   esp: %08lx\n",
+		regs->esi, regs->edi, regs->ebp, esp);
+	printk(KERN_EMERG "ds: %04x   es: %04x   fs: %04x  gs: %04x  ss: %04x\n",
+	       regs->xds & 0xffff, regs->xes & 0xffff, regs->xfs & 0xffff, gs, ss);
+	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
+		TASK_COMM_LEN, current->comm, current->pid,
+		current_thread_info(), current, task_thread_info(current));
+	/*
+	 * When in-kernel, we also print out the stack and code at the
+	 * time of the fault..
+	 */
+	if (in_kernel) {
+		u8 *eip;
+		unsigned int code_prologue = code_bytes * 43 / 64;
+		unsigned int code_len = code_bytes;
+		unsigned char c;
+
+		printk("\n" KERN_EMERG "Stack: ");
+		show_stack_log_lvl(NULL, regs, (unsigned long *)esp, KERN_EMERG);
+
+		printk(KERN_EMERG "Code: ");
+
+		eip = (u8 *)regs->eip - code_prologue;
+		if (eip < (u8 *)PAGE_OFFSET ||
+			probe_kernel_address(eip, c)) {
+			/* try starting at EIP */
+			eip = (u8 *)regs->eip;
+			code_len = code_len - code_prologue + 1;
+		}
+		for (i = 0; i < code_len; i++, eip++) {
+			if (eip < (u8 *)PAGE_OFFSET ||
+				probe_kernel_address(eip, c)) {
+				printk(" Bad EIP value.");
+				break;
+			}
+			if (eip == (u8 *)regs->eip)
+				printk("<%02x> ", c);
+			else
+				printk("%02x ", c);
+		}
+	}
+	printk("\n");
+}	
+
+int is_valid_bugaddr(unsigned long eip)
+{
+	unsigned short ud2;
+
+	if (eip < PAGE_OFFSET)
+		return 0;
+	if (probe_kernel_address((unsigned short *)eip, ud2))
+		return 0;
+
+	return ud2 == 0x0b0f;
+}
+
+/*
+ * This is gone through when something in the kernel has done something bad and
+ * is about to be terminated.
+ */
+void die(const char * str, struct pt_regs * regs, long err)
+{
+	static struct {
+		spinlock_t lock;
+		u32 lock_owner;
+		int lock_owner_depth;
+	} die = {
+		.lock =			__SPIN_LOCK_UNLOCKED(die.lock),
+		.lock_owner =		-1,
+		.lock_owner_depth =	0
+	};
+	static int die_counter;
+	unsigned long flags;
+
+	oops_enter();
+
+	if (die.lock_owner != raw_smp_processor_id()) {
+		console_verbose();
+		spin_lock_irqsave(&die.lock, flags);
+		die.lock_owner = smp_processor_id();
+		die.lock_owner_depth = 0;
+		bust_spinlocks(1);
+	}
+	else
+		local_save_flags(flags);
+
+	if (++die.lock_owner_depth < 3) {
+		int nl = 0;
+		unsigned long esp;
+		unsigned short ss;
+
+		report_bug(regs->eip, regs);
+
+		printk(KERN_EMERG "%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
+#ifdef CONFIG_PREEMPT
+		printk(KERN_EMERG "PREEMPT ");
+		nl = 1;
+#endif
+#ifdef CONFIG_SMP
+		if (!nl)
+			printk(KERN_EMERG);
+		printk("SMP ");
+		nl = 1;
+#endif
+#ifdef CONFIG_DEBUG_PAGEALLOC
+		if (!nl)
+			printk(KERN_EMERG);
+		printk("DEBUG_PAGEALLOC");
+		nl = 1;
+#endif
+		if (nl)
+			printk("\n");
+		if (notify_die(DIE_OOPS, str, regs, err,
+					current->thread.trap_no, SIGSEGV) !=
+				NOTIFY_STOP) {
+			show_registers(regs);
+			/* Executive summary in case the oops scrolled away */
+			esp = (unsigned long) (&regs->esp);
+			savesegment(ss, ss);
+			if (user_mode(regs)) {
+				esp = regs->esp;
+				ss = regs->xss & 0xffff;
+			}
+			printk(KERN_EMERG "EIP: [<%08lx>] ", regs->eip);
+			print_symbol("%s", regs->eip);
+			printk(" SS:ESP %04x:%08lx\n", ss, esp);
+		}
+		else
+			regs = NULL;
+  	} else
+		printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
+
+	bust_spinlocks(0);
+	die.lock_owner = -1;
+	add_taint(TAINT_DIE);
+	spin_unlock_irqrestore(&die.lock, flags);
+
+	if (!regs)
+		return;
+
+	if (kexec_should_crash(current))
+		crash_kexec(regs);
+
+	if (in_interrupt())
+		panic("Fatal exception in interrupt");
+
+	if (panic_on_oops)
+		panic("Fatal exception");
+
+	oops_exit();
+	do_exit(SIGSEGV);
+}
+
+static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
+{
+	if (!user_mode_vm(regs))
+		die(str, regs, err);
+}
+
+static void __kprobes do_trap(int trapnr, int signr, char *str, int vm86,
+			      struct pt_regs * regs, long error_code,
+			      siginfo_t *info)
+{
+	struct task_struct *tsk = current;
+
+	if (regs->eflags & VM_MASK) {
+		if (vm86)
+			goto vm86_trap;
+		goto trap_signal;
+	}
+
+	if (!user_mode(regs))
+		goto kernel_trap;
+
+	trap_signal: {
+		/*
+		 * We want error_code and trap_no set for userspace faults and
+		 * kernelspace faults which result in die(), but not
+		 * kernelspace faults which are fixed up.  die() gives the
+		 * process no chance to handle the signal and notice the
+		 * kernel fault information, so that won't result in polluting
+		 * the information about previously queued, but not yet
+		 * delivered, faults.  See also do_general_protection below.
+		 */
+		tsk->thread.error_code = error_code;
+		tsk->thread.trap_no = trapnr;
+
+		if (info)
+			force_sig_info(signr, info, tsk);
+		else
+			force_sig(signr, tsk);
+		return;
+	}
+
+	kernel_trap: {
+		if (!fixup_exception(regs)) {
+			tsk->thread.error_code = error_code;
+			tsk->thread.trap_no = trapnr;
+			die(str, regs, error_code);
+		}
+		return;
+	}
+
+	vm86_trap: {
+		int ret = handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, trapnr);
+		if (ret) goto trap_signal;
+		return;
+	}
+}
+
+#define DO_ERROR(trapnr, signr, str, name) \
+fastcall void do_##name(struct pt_regs * regs, long error_code) \
+{ \
+	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
+						== NOTIFY_STOP) \
+		return; \
+	do_trap(trapnr, signr, str, 0, regs, error_code, NULL); \
+}
+
+#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr, irq) \
+fastcall void do_##name(struct pt_regs * regs, long error_code) \
+{ \
+	siginfo_t info; \
+	if (irq) \
+		local_irq_enable(); \
+	info.si_signo = signr; \
+	info.si_errno = 0; \
+	info.si_code = sicode; \
+	info.si_addr = (void __user *)siaddr; \
+	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
+						== NOTIFY_STOP) \
+		return; \
+	do_trap(trapnr, signr, str, 0, regs, error_code, &info); \
+}
+
+#define DO_VM86_ERROR(trapnr, signr, str, name) \
+fastcall void do_##name(struct pt_regs * regs, long error_code) \
+{ \
+	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
+						== NOTIFY_STOP) \
+		return; \
+	do_trap(trapnr, signr, str, 1, regs, error_code, NULL); \
+}
+
+#define DO_VM86_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
+fastcall void do_##name(struct pt_regs * regs, long error_code) \
+{ \
+	siginfo_t info; \
+	info.si_signo = signr; \
+	info.si_errno = 0; \
+	info.si_code = sicode; \
+	info.si_addr = (void __user *)siaddr; \
+	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
+						== NOTIFY_STOP) \
+		return; \
+	do_trap(trapnr, signr, str, 1, regs, error_code, &info); \
+}
+
+DO_VM86_ERROR_INFO( 0, SIGFPE,  "divide error", divide_error, FPE_INTDIV, regs->eip)
+#ifndef CONFIG_KPROBES
+DO_VM86_ERROR( 3, SIGTRAP, "int3", int3)
+#endif
+DO_VM86_ERROR( 4, SIGSEGV, "overflow", overflow)
+DO_VM86_ERROR( 5, SIGSEGV, "bounds", bounds)
+DO_ERROR_INFO( 6, SIGILL,  "invalid opcode", invalid_op, ILL_ILLOPN, regs->eip, 0)
+DO_ERROR( 9, SIGFPE,  "coprocessor segment overrun", coprocessor_segment_overrun)
+DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
+DO_ERROR(11, SIGBUS,  "segment not present", segment_not_present)
+DO_ERROR(12, SIGBUS,  "stack segment", stack_segment)
+DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0, 0)
+DO_ERROR_INFO(32, SIGSEGV, "iret exception", iret_error, ILL_BADSTK, 0, 1)
+
+fastcall void __kprobes do_general_protection(struct pt_regs * regs,
+					      long error_code)
+{
+	int cpu = get_cpu();
+	struct tss_struct *tss = &per_cpu(init_tss, cpu);
+	struct thread_struct *thread = &current->thread;
+
+	/*
+	 * Perform the lazy TSS's I/O bitmap copy. If the TSS has an
+	 * invalid offset set (the LAZY one) and the faulting thread has
+	 * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS
+	 * and we set the offset field correctly. Then we let the CPU to
+	 * restart the faulting instruction.
+	 */
+	if (tss->x86_tss.io_bitmap_base == INVALID_IO_BITMAP_OFFSET_LAZY &&
+	    thread->io_bitmap_ptr) {
+		memcpy(tss->io_bitmap, thread->io_bitmap_ptr,
+		       thread->io_bitmap_max);
+		/*
+		 * If the previously set map was extending to higher ports
+		 * than the current one, pad extra space with 0xff (no access).
+		 */
+		if (thread->io_bitmap_max < tss->io_bitmap_max)
+			memset((char *) tss->io_bitmap +
+				thread->io_bitmap_max, 0xff,
+				tss->io_bitmap_max - thread->io_bitmap_max);
+		tss->io_bitmap_max = thread->io_bitmap_max;
+		tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
+		tss->io_bitmap_owner = thread;
+		put_cpu();
+		return;
+	}
+	put_cpu();
+
+	if (regs->eflags & VM_MASK)
+		goto gp_in_vm86;
+
+	if (!user_mode(regs))
+		goto gp_in_kernel;
+
+	current->thread.error_code = error_code;
+	current->thread.trap_no = 13;
+	if (show_unhandled_signals && unhandled_signal(current, SIGSEGV) &&
+	    printk_ratelimit())
+		printk(KERN_INFO
+		    "%s[%d] general protection eip:%lx esp:%lx error:%lx\n",
+		    current->comm, current->pid,
+		    regs->eip, regs->esp, error_code);
+
+	force_sig(SIGSEGV, current);
+	return;
+
+gp_in_vm86:
+	local_irq_enable();
+	handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);
+	return;
+
+gp_in_kernel:
+	if (!fixup_exception(regs)) {
+		current->thread.error_code = error_code;
+		current->thread.trap_no = 13;
+		if (notify_die(DIE_GPF, "general protection fault", regs,
+				error_code, 13, SIGSEGV) == NOTIFY_STOP)
+			return;
+		die("general protection fault", regs, error_code);
+	}
+}
+
+static __kprobes void
+mem_parity_error(unsigned char reason, struct pt_regs * regs)
+{
+	printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x on "
+		"CPU %d.\n", reason, smp_processor_id());
+	printk(KERN_EMERG "You have some hardware problem, likely on the PCI bus.\n");
+
+#if defined(CONFIG_EDAC)
+	if(edac_handler_set()) {
+		edac_atomic_assert_error();
+		return;
+	}
+#endif
+
+	if (panic_on_unrecovered_nmi)
+                panic("NMI: Not continuing");
+
+	printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
+
+	/* Clear and disable the memory parity error line. */
+	clear_mem_error(reason);
+}
+
+static __kprobes void
+io_check_error(unsigned char reason, struct pt_regs * regs)
+{
+	unsigned long i;
+
+	printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n");
+	show_registers(regs);
+
+	/* Re-enable the IOCK line, wait for a few seconds */
+	reason = (reason & 0xf) | 8;
+	outb(reason, 0x61);
+	i = 2000;
+	while (--i) udelay(1000);
+	reason &= ~8;
+	outb(reason, 0x61);
+}
+
+static __kprobes void
+unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
+{
+#ifdef CONFIG_MCA
+	/* Might actually be able to figure out what the guilty party
+	* is. */
+	if( MCA_bus ) {
+		mca_handle_nmi();
+		return;
+	}
+#endif
+	printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x on "
+		"CPU %d.\n", reason, smp_processor_id());
+	printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n");
+	if (panic_on_unrecovered_nmi)
+                panic("NMI: Not continuing");
+
+	printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
+}
+
+static DEFINE_SPINLOCK(nmi_print_lock);
+
+void __kprobes die_nmi(struct pt_regs *regs, const char *msg)
+{
+	if (notify_die(DIE_NMIWATCHDOG, msg, regs, 0, 2, SIGINT) ==
+	    NOTIFY_STOP)
+		return;
+
+	spin_lock(&nmi_print_lock);
+	/*
+	* We are in trouble anyway, lets at least try
+	* to get a message out.
+	*/
+	bust_spinlocks(1);
+	printk(KERN_EMERG "%s", msg);
+	printk(" on CPU%d, eip %08lx, registers:\n",
+		smp_processor_id(), regs->eip);
+	show_registers(regs);
+	console_silent();
+	spin_unlock(&nmi_print_lock);
+	bust_spinlocks(0);
+
+	/* If we are in kernel we are probably nested up pretty bad
+	 * and might aswell get out now while we still can.
+	*/
+	if (!user_mode_vm(regs)) {
+		current->thread.trap_no = 2;
+		crash_kexec(regs);
+	}
+
+	do_exit(SIGSEGV);
+}
+
+static __kprobes void default_do_nmi(struct pt_regs * regs)
+{
+	unsigned char reason = 0;
+
+	/* Only the BSP gets external NMIs from the system.  */
+	if (!smp_processor_id())
+		reason = get_nmi_reason();
+ 
+	if (!(reason & 0xc0)) {
+		if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
+							== NOTIFY_STOP)
+			return;
+#ifdef CONFIG_X86_LOCAL_APIC
+		/*
+		 * Ok, so this is none of the documented NMI sources,
+		 * so it must be the NMI watchdog.
+		 */
+		if (nmi_watchdog_tick(regs, reason))
+			return;
+		if (!do_nmi_callback(regs, smp_processor_id()))
+#endif
+			unknown_nmi_error(reason, regs);
+
+		return;
+	}
+	if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
+		return;
+	if (reason & 0x80)
+		mem_parity_error(reason, regs);
+	if (reason & 0x40)
+		io_check_error(reason, regs);
+	/*
+	 * Reassert NMI in case it became active meanwhile
+	 * as it's edge-triggered.
+	 */
+	reassert_nmi();
+}
+
+static int ignore_nmis;
+
+fastcall __kprobes void do_nmi(struct pt_regs * regs, long error_code)
+{
+	int cpu;
+
+	nmi_enter();
+
+	cpu = smp_processor_id();
+
+	++nmi_count(cpu);
+
+	if (!ignore_nmis)
+		default_do_nmi(regs);
+
+	nmi_exit();
+}
+
+void stop_nmi(void)
+{
+	acpi_nmi_disable();
+	ignore_nmis++;
+}
+
+void restart_nmi(void)
+{
+	ignore_nmis--;
+	acpi_nmi_enable();
+}
+
+#ifdef CONFIG_KPROBES
+fastcall void __kprobes do_int3(struct pt_regs *regs, long error_code)
+{
+	if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
+			== NOTIFY_STOP)
+		return;
+	/* This is an interrupt gate, because kprobes wants interrupts
+	disabled.  Normal trap handlers don't. */
+	restore_interrupts(regs);
+	do_trap(3, SIGTRAP, "int3", 1, regs, error_code, NULL);
+}
+#endif
+
+/*
+ * Our handling of the processor debug registers is non-trivial.
+ * We do not clear them on entry and exit from the kernel. Therefore
+ * it is possible to get a watchpoint trap here from inside the kernel.
+ * However, the code in ./ptrace.c has ensured that the user can
+ * only set watchpoints on userspace addresses. Therefore the in-kernel
+ * watchpoint trap can only occur in code which is reading/writing
+ * from user space. Such code must not hold kernel locks (since it
+ * can equally take a page fault), therefore it is safe to call
+ * force_sig_info even though that claims and releases locks.
+ * 
+ * Code in ./signal.c ensures that the debug control register
+ * is restored before we deliver any signal, and therefore that
+ * user code runs with the correct debug control register even though
+ * we clear it here.
+ *
+ * Being careful here means that we don't have to be as careful in a
+ * lot of more complicated places (task switching can be a bit lazy
+ * about restoring all the debug state, and ptrace doesn't have to
+ * find every occurrence of the TF bit that could be saved away even
+ * by user code)
+ */
+fastcall void __kprobes do_debug(struct pt_regs * regs, long error_code)
+{
+	unsigned int condition;
+	struct task_struct *tsk = current;
+
+	get_debugreg(condition, 6);
+
+	if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
+					SIGTRAP) == NOTIFY_STOP)
+		return;
+	/* It's safe to allow irq's after DR6 has been saved */
+	if (regs->eflags & X86_EFLAGS_IF)
+		local_irq_enable();
+
+	/* Mask out spurious debug traps due to lazy DR7 setting */
+	if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) {
+		if (!tsk->thread.debugreg[7])
+			goto clear_dr7;
+	}
+
+	if (regs->eflags & VM_MASK)
+		goto debug_vm86;
+
+	/* Save debug status register where ptrace can see it */
+	tsk->thread.debugreg[6] = condition;
+
+	/*
+	 * Single-stepping through TF: make sure we ignore any events in
+	 * kernel space (but re-enable TF when returning to user mode).
+	 */
+	if (condition & DR_STEP) {
+		/*
+		 * We already checked v86 mode above, so we can
+		 * check for kernel mode by just checking the CPL
+		 * of CS.
+		 */
+		if (!user_mode(regs))
+			goto clear_TF_reenable;
+	}
+
+	/* Ok, finally something we can handle */
+	send_sigtrap(tsk, regs, error_code);
+
+	/* Disable additional traps. They'll be re-enabled when
+	 * the signal is delivered.
+	 */
+clear_dr7:
+	set_debugreg(0, 7);
+	return;
+
+debug_vm86:
+	handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1);
+	return;
+
+clear_TF_reenable:
+	set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
+	regs->eflags &= ~TF_MASK;
+	return;
+}
+
+/*
+ * Note that we play around with the 'TS' bit in an attempt to get
+ * the correct behaviour even in the presence of the asynchronous
+ * IRQ13 behaviour
+ */
+void math_error(void __user *eip)
+{
+	struct task_struct * task;
+	siginfo_t info;
+	unsigned short cwd, swd;
+
+	/*
+	 * Save the info for the exception handler and clear the error.
+	 */
+	task = current;
+	save_init_fpu(task);
+	task->thread.trap_no = 16;
+	task->thread.error_code = 0;
+	info.si_signo = SIGFPE;
+	info.si_errno = 0;
+	info.si_code = __SI_FAULT;
+	info.si_addr = eip;
+	/*
+	 * (~cwd & swd) will mask out exceptions that are not set to unmasked
+	 * status.  0x3f is the exception bits in these regs, 0x200 is the
+	 * C1 reg you need in case of a stack fault, 0x040 is the stack
+	 * fault bit.  We should only be taking one exception at a time,
+	 * so if this combination doesn't produce any single exception,
+	 * then we have a bad program that isn't syncronizing its FPU usage
+	 * and it will suffer the consequences since we won't be able to
+	 * fully reproduce the context of the exception
+	 */
+	cwd = get_fpu_cwd(task);
+	swd = get_fpu_swd(task);
+	switch (swd & ~cwd & 0x3f) {
+		case 0x000: /* No unmasked exception */
+			return;
+		default:    /* Multiple exceptions */
+			break;
+		case 0x001: /* Invalid Op */
+			/*
+			 * swd & 0x240 == 0x040: Stack Underflow
+			 * swd & 0x240 == 0x240: Stack Overflow
+			 * User must clear the SF bit (0x40) if set
+			 */
+			info.si_code = FPE_FLTINV;
+			break;
+		case 0x002: /* Denormalize */
+		case 0x010: /* Underflow */
+			info.si_code = FPE_FLTUND;
+			break;
+		case 0x004: /* Zero Divide */
+			info.si_code = FPE_FLTDIV;
+			break;
+		case 0x008: /* Overflow */
+			info.si_code = FPE_FLTOVF;
+			break;
+		case 0x020: /* Precision */
+			info.si_code = FPE_FLTRES;
+			break;
+	}
+	force_sig_info(SIGFPE, &info, task);
+}
+
+fastcall void do_coprocessor_error(struct pt_regs * regs, long error_code)
+{
+	ignore_fpu_irq = 1;
+	math_error((void __user *)regs->eip);
+}
+
+static void simd_math_error(void __user *eip)
+{
+	struct task_struct * task;
+	siginfo_t info;
+	unsigned short mxcsr;
+
+	/*
+	 * Save the info for the exception handler and clear the error.
+	 */
+	task = current;
+	save_init_fpu(task);
+	task->thread.trap_no = 19;
+	task->thread.error_code = 0;
+	info.si_signo = SIGFPE;
+	info.si_errno = 0;
+	info.si_code = __SI_FAULT;
+	info.si_addr = eip;
+	/*
+	 * The SIMD FPU exceptions are handled a little differently, as there
+	 * is only a single status/control register.  Thus, to determine which
+	 * unmasked exception was caught we must mask the exception mask bits
+	 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
+	 */
+	mxcsr = get_fpu_mxcsr(task);
+	switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) {
+		case 0x000:
+		default:
+			break;
+		case 0x001: /* Invalid Op */
+			info.si_code = FPE_FLTINV;
+			break;
+		case 0x002: /* Denormalize */
+		case 0x010: /* Underflow */
+			info.si_code = FPE_FLTUND;
+			break;
+		case 0x004: /* Zero Divide */
+			info.si_code = FPE_FLTDIV;
+			break;
+		case 0x008: /* Overflow */
+			info.si_code = FPE_FLTOVF;
+			break;
+		case 0x020: /* Precision */
+			info.si_code = FPE_FLTRES;
+			break;
+	}
+	force_sig_info(SIGFPE, &info, task);
+}
+
+fastcall void do_simd_coprocessor_error(struct pt_regs * regs,
+					  long error_code)
+{
+	if (cpu_has_xmm) {
+		/* Handle SIMD FPU exceptions on PIII+ processors. */
+		ignore_fpu_irq = 1;
+		simd_math_error((void __user *)regs->eip);
+	} else {
+		/*
+		 * Handle strange cache flush from user space exception
+		 * in all other cases.  This is undocumented behaviour.
+		 */
+		if (regs->eflags & VM_MASK) {
+			handle_vm86_fault((struct kernel_vm86_regs *)regs,
+					  error_code);
+			return;
+		}
+		current->thread.trap_no = 19;
+		current->thread.error_code = error_code;
+		die_if_kernel("cache flush denied", regs, error_code);
+		force_sig(SIGSEGV, current);
+	}
+}
+
+fastcall void do_spurious_interrupt_bug(struct pt_regs * regs,
+					  long error_code)
+{
+#if 0
+	/* No need to warn about this any longer. */
+	printk("Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
+#endif
+}
+
+fastcall unsigned long patch_espfix_desc(unsigned long uesp,
+					  unsigned long kesp)
+{
+	struct desc_struct *gdt = __get_cpu_var(gdt_page).gdt;
+	unsigned long base = (kesp - uesp) & -THREAD_SIZE;
+	unsigned long new_kesp = kesp - base;
+	unsigned long lim_pages = (new_kesp | (THREAD_SIZE - 1)) >> PAGE_SHIFT;
+	__u64 desc = *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS];
+	/* Set up base for espfix segment */
+ 	desc &= 0x00f0ff0000000000ULL;
+ 	desc |=	((((__u64)base) << 16) & 0x000000ffffff0000ULL) |
+		((((__u64)base) << 32) & 0xff00000000000000ULL) |
+		((((__u64)lim_pages) << 32) & 0x000f000000000000ULL) |
+		(lim_pages & 0xffff);
+	*(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS] = desc;
+	return new_kesp;
+}
+
+/*
+ *  'math_state_restore()' saves the current math information in the
+ * old math state array, and gets the new ones from the current task
+ *
+ * Careful.. There are problems with IBM-designed IRQ13 behaviour.
+ * Don't touch unless you *really* know how it works.
+ *
+ * Must be called with kernel preemption disabled (in this case,
+ * local interrupts are disabled at the call-site in entry.S).
+ */
+asmlinkage void math_state_restore(void)
+{
+	struct thread_info *thread = current_thread_info();
+	struct task_struct *tsk = thread->task;
+
+	clts();		/* Allow maths ops (or we recurse) */
+	if (!tsk_used_math(tsk))
+		init_fpu(tsk);
+	restore_fpu(tsk);
+	thread->status |= TS_USEDFPU;	/* So we fnsave on switch_to() */
+	tsk->fpu_counter++;
+}
+EXPORT_SYMBOL_GPL(math_state_restore);
+
+#ifndef CONFIG_MATH_EMULATION
+
+asmlinkage void math_emulate(long arg)
+{
+	printk(KERN_EMERG "math-emulation not enabled and no coprocessor found.\n");
+	printk(KERN_EMERG "killing %s.\n",current->comm);
+	force_sig(SIGFPE,current);
+	schedule();
+}
+
+#endif /* CONFIG_MATH_EMULATION */
+
+#ifdef CONFIG_X86_F00F_BUG
+void __init trap_init_f00f_bug(void)
+{
+	__set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);
+
+	/*
+	 * Update the IDT descriptor and reload the IDT so that
+	 * it uses the read-only mapped virtual address.
+	 */
+	idt_descr.address = fix_to_virt(FIX_F00F_IDT);
+	load_idt(&idt_descr);
+}
+#endif
+
+/*
+ * This needs to use 'idt_table' rather than 'idt', and
+ * thus use the _nonmapped_ version of the IDT, as the
+ * Pentium F0 0F bugfix can have resulted in the mapped
+ * IDT being write-protected.
+ */
+void set_intr_gate(unsigned int n, void *addr)
+{
+	_set_gate(n, DESCTYPE_INT, addr, __KERNEL_CS);
+}
+
+/*
+ * This routine sets up an interrupt gate at directory privilege level 3.
+ */
+static inline void set_system_intr_gate(unsigned int n, void *addr)
+{
+	_set_gate(n, DESCTYPE_INT | DESCTYPE_DPL3, addr, __KERNEL_CS);
+}
+
+static void __init set_trap_gate(unsigned int n, void *addr)
+{
+	_set_gate(n, DESCTYPE_TRAP, addr, __KERNEL_CS);
+}
+
+static void __init set_system_gate(unsigned int n, void *addr)
+{
+	_set_gate(n, DESCTYPE_TRAP | DESCTYPE_DPL3, addr, __KERNEL_CS);
+}
+
+static void __init set_task_gate(unsigned int n, unsigned int gdt_entry)
+{
+	_set_gate(n, DESCTYPE_TASK, (void *)0, (gdt_entry<<3));
+}
+
+
+void __init trap_init(void)
+{
+#ifdef CONFIG_EISA
+	void __iomem *p = ioremap(0x0FFFD9, 4);
+	if (readl(p) == 'E'+('I'<<8)+('S'<<16)+('A'<<24)) {
+		EISA_bus = 1;
+	}
+	iounmap(p);
+#endif
+
+#ifdef CONFIG_X86_LOCAL_APIC
+	init_apic_mappings();
+#endif
+
+	set_trap_gate(0,&divide_error);
+	set_intr_gate(1,&debug);
+	set_intr_gate(2,&nmi);
+	set_system_intr_gate(3, &int3); /* int3/4 can be called from all */
+	set_system_gate(4,&overflow);
+	set_trap_gate(5,&bounds);
+	set_trap_gate(6,&invalid_op);
+	set_trap_gate(7,&device_not_available);
+	set_task_gate(8,GDT_ENTRY_DOUBLEFAULT_TSS);
+	set_trap_gate(9,&coprocessor_segment_overrun);
+	set_trap_gate(10,&invalid_TSS);
+	set_trap_gate(11,&segment_not_present);
+	set_trap_gate(12,&stack_segment);
+	set_trap_gate(13,&general_protection);
+	set_intr_gate(14,&page_fault);
+	set_trap_gate(15,&spurious_interrupt_bug);
+	set_trap_gate(16,&coprocessor_error);
+	set_trap_gate(17,&alignment_check);
+#ifdef CONFIG_X86_MCE
+	set_trap_gate(18,&machine_check);
+#endif
+	set_trap_gate(19,&simd_coprocessor_error);
+
+	if (cpu_has_fxsr) {
+		/*
+		 * Verify that the FXSAVE/FXRSTOR data will be 16-byte aligned.
+		 * Generates a compile-time "error: zero width for bit-field" if
+		 * the alignment is wrong.
+		 */
+		struct fxsrAlignAssert {
+			int _:!(offsetof(struct task_struct,
+					thread.i387.fxsave) & 15);
+		};
+
+		printk(KERN_INFO "Enabling fast FPU save and restore... ");
+		set_in_cr4(X86_CR4_OSFXSR);
+		printk("done.\n");
+	}
+	if (cpu_has_xmm) {
+		printk(KERN_INFO "Enabling unmasked SIMD FPU exception "
+				"support... ");
+		set_in_cr4(X86_CR4_OSXMMEXCPT);
+		printk("done.\n");
+	}
+
+	set_system_gate(SYSCALL_VECTOR,&system_call);
+
+	/*
+	 * Should be a barrier for any external CPU state.
+	 */
+	cpu_init();
+
+	trap_init_hook();
+}
+
+static int __init kstack_setup(char *s)
+{
+	kstack_depth_to_print = simple_strtoul(s, NULL, 0);
+	return 1;
+}
+__setup("kstack=", kstack_setup);
+
+static int __init code_bytes_setup(char *s)
+{
+	code_bytes = simple_strtoul(s, NULL, 0);
+	if (code_bytes > 8192)
+		code_bytes = 8192;
+
+	return 1;
+}
+__setup("code_bytes=", code_bytes_setup);