i386: prepare shared kernel/traps.c
authorThomas Gleixner <tglx@linutronix.de>
Thu, 11 Oct 2007 09:11:47 +0000 (11:11 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 11 Oct 2007 09:11:47 +0000 (11:11 +0200)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/i386/kernel/Makefile
arch/i386/kernel/traps.c [deleted file]
arch/i386/kernel/traps_32.c [new file with mode: 0644]

index 9d33b00de659af6b96e0899cae5394927d25cda7..bd44e20d2cd99fec390b4ef0182da83867d36dc3 100644 (file)
@@ -4,7 +4,7 @@
 
 extra-y := head.o init_task.o vmlinux.lds
 
-obj-y  := process.o signal.o entry.o traps.o irq.o \
+obj-y  := process.o signal.o entry.o traps_32.o irq.o \
                ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \
                pci-dma.o i386_ksyms.o i387.o bootflag.o e820.o\
                quirks.o i8237.o topology.o alternative.o i8253.o tsc.o
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
deleted file mode 100644 (file)
index 47b0bef..0000000
+++ /dev/null
@@ -1,1250 +0,0 @@
-/*
- *  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);
diff --git a/arch/i386/kernel/traps_32.c b/arch/i386/kernel/traps_32.c
new file mode 100644 (file)
index 0000000..47b0bef
--- /dev/null
@@ -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);