Logo Search packages:      
Sourcecode: linux version File versions  Download package

traps.c

/*
 *  arch/s390/kernel/traps.c
 *
 *  S390 version
 *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
 *
 *  Derived from "arch/i386/kernel/traps.c"
 *    Copyright (C) 1991, 1992 Linus Torvalds
 */

/*
 * '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/ptrace.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/kdebug.h>
#include <linux/kallsyms.h>
#include <linux/reboot.h>
#include <linux/kprobes.h>
#include <linux/bug.h>
#include <linux/utsname.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <asm/mathemu.h>
#include <asm/cpcmd.h>
#include <asm/s390_ext.h>
#include <asm/lowcore.h>
#include <asm/debug.h>
#include "entry.h"

pgm_check_handler_t *pgm_check_table[128];

#ifdef CONFIG_SYSCTL
#ifdef CONFIG_PROCESS_DEBUG
int sysctl_userprocess_debug = 1;
#else
int sysctl_userprocess_debug = 0;
#endif
#endif

extern pgm_check_handler_t do_protection_exception;
extern pgm_check_handler_t do_dat_exception;
extern pgm_check_handler_t do_asce_exception;

#define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })

#ifndef CONFIG_64BIT
#define FOURLONG "%08lx %08lx %08lx %08lx\n"
static int kstack_depth_to_print = 12;
#else /* CONFIG_64BIT */
#define FOURLONG "%016lx %016lx %016lx %016lx\n"
static int kstack_depth_to_print = 20;
#endif /* CONFIG_64BIT */

/*
 * For show_trace we have tree different stack to consider:
 *   - the panic stack which is used if the kernel stack has overflown
 *   - the asynchronous interrupt stack (cpu related)
 *   - the synchronous kernel stack (process related)
 * The stack trace can start at any of the three stack and can potentially
 * touch all of them. The order is: panic stack, async stack, sync stack.
 */
static unsigned long
__show_trace(unsigned long sp, unsigned long low, unsigned long high)
{
      struct stack_frame *sf;
      struct pt_regs *regs;

      while (1) {
            sp = sp & PSW_ADDR_INSN;
            if (sp < low || sp > high - sizeof(*sf))
                  return sp;
            sf = (struct stack_frame *) sp;
            printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
            print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
            /* Follow the backchain. */
            while (1) {
                  low = sp;
                  sp = sf->back_chain & PSW_ADDR_INSN;
                  if (!sp)
                        break;
                  if (sp <= low || sp > high - sizeof(*sf))
                        return sp;
                  sf = (struct stack_frame *) sp;
                  printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
                  print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
            }
            /* Zero backchain detected, check for interrupt frame. */
            sp = (unsigned long) (sf + 1);
            if (sp <= low || sp > high - sizeof(*regs))
                  return sp;
            regs = (struct pt_regs *) sp;
            printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
            print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
            low = sp;
            sp = regs->gprs[15];
      }
}

static void show_trace(struct task_struct *task, unsigned long *stack)
{
      register unsigned long __r15 asm ("15");
      unsigned long sp;

      sp = (unsigned long) stack;
      if (!sp)
            sp = task ? task->thread.ksp : __r15;
      printk("Call Trace:\n");
#ifdef CONFIG_CHECK_STACK
      sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
                    S390_lowcore.panic_stack);
#endif
      sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
                    S390_lowcore.async_stack);
      if (task)
            __show_trace(sp, (unsigned long) task_stack_page(task),
                       (unsigned long) task_stack_page(task) + THREAD_SIZE);
      else
            __show_trace(sp, S390_lowcore.thread_info,
                       S390_lowcore.thread_info + THREAD_SIZE);
      if (!task)
            task = current;
      debug_show_held_locks(task);
}

void show_stack(struct task_struct *task, unsigned long *sp)
{
      register unsigned long * __r15 asm ("15");
      unsigned long *stack;
      int i;

      if (!sp)
            stack = task ? (unsigned long *) task->thread.ksp : __r15;
      else
            stack = sp;

      for (i = 0; i < kstack_depth_to_print; i++) {
            if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
                  break;
            if (i && ((i * sizeof (long) % 32) == 0))
                  printk("\n       ");
            printk("%p ", (void *)*stack++);
      }
      printk("\n");
      show_trace(task, sp);
}

static void show_last_breaking_event(struct pt_regs *regs)
{
#ifdef CONFIG_64BIT
      printk("Last Breaking-Event-Address:\n");
      printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
      print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
#endif
}

/*
 * The architecture-independent dump_stack generator
 */
void dump_stack(void)
{
      printk("CPU: %d %s %s %.*s\n",
             task_thread_info(current)->cpu, print_tainted(),
             init_utsname()->release,
             (int)strcspn(init_utsname()->version, " "),
             init_utsname()->version);
      printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
             current->comm, current->pid, current,
             (void *) current->thread.ksp);
      show_stack(NULL, NULL);
}
EXPORT_SYMBOL(dump_stack);

static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
{
      return (regs->psw.mask & bits) / ((~bits + 1) & bits);
}

void show_registers(struct pt_regs *regs)
{
      char *mode;

      mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
      printk("%s PSW : %p %p",
             mode, (void *) regs->psw.mask,
             (void *) regs->psw.addr);
      print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
      printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
             "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
             mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
             mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
             mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
             mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
             mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
#ifdef CONFIG_64BIT
      printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
#endif
      printk("\n%s GPRS: " FOURLONG, mode,
             regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
      printk("           " FOURLONG,
             regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
      printk("           " FOURLONG,
             regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
      printk("           " FOURLONG,
             regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);

      show_code(regs);
}     

void show_regs(struct pt_regs *regs)
{
      print_modules();
      printk("CPU: %d %s %s %.*s\n",
             task_thread_info(current)->cpu, print_tainted(),
             init_utsname()->release,
             (int)strcspn(init_utsname()->version, " "),
             init_utsname()->version);
      printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
             current->comm, current->pid, current,
             (void *) current->thread.ksp);
      show_registers(regs);
      /* Show stack backtrace if pt_regs is from kernel mode */
      if (!(regs->psw.mask & PSW_MASK_PSTATE))
            show_trace(NULL, (unsigned long *) regs->gprs[15]);
      show_last_breaking_event(regs);
}

/* This is called from fs/proc/array.c */
void task_show_regs(struct seq_file *m, struct task_struct *task)
{
      struct pt_regs *regs;

      regs = task_pt_regs(task);
      seq_printf(m, "task: %p, ksp: %p\n",
                   task, (void *)task->thread.ksp);
      seq_printf(m, "User PSW : %p %p\n",
                   (void *) regs->psw.mask, (void *)regs->psw.addr);

      seq_printf(m, "User GPRS: " FOURLONG,
                    regs->gprs[0], regs->gprs[1],
                    regs->gprs[2], regs->gprs[3]);
      seq_printf(m, "           " FOURLONG,
                    regs->gprs[4], regs->gprs[5],
                    regs->gprs[6], regs->gprs[7]);
      seq_printf(m, "           " FOURLONG,
                    regs->gprs[8], regs->gprs[9],
                    regs->gprs[10], regs->gprs[11]);
      seq_printf(m, "           " FOURLONG,
                    regs->gprs[12], regs->gprs[13],
                    regs->gprs[14], regs->gprs[15]);
      seq_printf(m, "User ACRS: %08x %08x %08x %08x\n",
                    task->thread.acrs[0], task->thread.acrs[1],
                    task->thread.acrs[2], task->thread.acrs[3]);
      seq_printf(m, "           %08x %08x %08x %08x\n",
                    task->thread.acrs[4], task->thread.acrs[5],
                    task->thread.acrs[6], task->thread.acrs[7]);
      seq_printf(m, "           %08x %08x %08x %08x\n",
                    task->thread.acrs[8], task->thread.acrs[9],
                    task->thread.acrs[10], task->thread.acrs[11]);
      seq_printf(m, "           %08x %08x %08x %08x\n",
                    task->thread.acrs[12], task->thread.acrs[13],
                    task->thread.acrs[14], task->thread.acrs[15]);
}

static DEFINE_SPINLOCK(die_lock);

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

      oops_enter();
      debug_stop_all();
      console_verbose();
      spin_lock_irq(&die_lock);
      bust_spinlocks(1);
      printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
#ifdef CONFIG_PREEMPT
      printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
      printk("SMP ");
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
      printk("DEBUG_PAGEALLOC");
#endif
      printk("\n");
      notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
      show_regs(regs);
      bust_spinlocks(0);
      add_taint(TAINT_DIE);
      spin_unlock_irq(&die_lock);
      if (in_interrupt())
            panic("Fatal exception in interrupt");
      if (panic_on_oops)
            panic("Fatal exception: panic_on_oops");
      oops_exit();
      do_exit(SIGSEGV);
}

static void inline
report_user_fault(long interruption_code, struct pt_regs *regs)
{
#if defined(CONFIG_SYSCTL)
      if (!sysctl_userprocess_debug)
            return;
#endif
#if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
      printk("User process fault: interruption code 0x%lX\n",
             interruption_code);
      show_regs(regs);
#endif
}

int is_valid_bugaddr(unsigned long addr)
{
      return 1;
}

static void __kprobes inline do_trap(long interruption_code, int signr,
                              char *str, struct pt_regs *regs,
                              siginfo_t *info)
{
      /*
       * We got all needed information from the lowcore and can
       * now safely switch on interrupts.
       */
        if (regs->psw.mask & PSW_MASK_PSTATE)
            local_irq_enable();

      if (notify_die(DIE_TRAP, str, regs, interruption_code,
                        interruption_code, signr) == NOTIFY_STOP)
            return;

        if (regs->psw.mask & PSW_MASK_PSTATE) {
                struct task_struct *tsk = current;

                tsk->thread.trap_no = interruption_code & 0xffff;
            force_sig_info(signr, info, tsk);
            report_user_fault(interruption_code, regs);
        } else {
                const struct exception_table_entry *fixup;
                fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
                if (fixup)
                        regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
            else {
                  enum bug_trap_type btt;

                  btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
                  if (btt == BUG_TRAP_TYPE_WARN)
                        return;
                  die(str, regs, interruption_code);
            }
        }
}

static inline void __user *get_check_address(struct pt_regs *regs)
{
      return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
}

void __kprobes do_single_step(struct pt_regs *regs)
{
      if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
                              SIGTRAP) == NOTIFY_STOP){
            return;
      }
      if ((current->ptrace & PT_PTRACED) != 0)
            force_sig(SIGTRAP, current);
}

static void default_trap_handler(struct pt_regs * regs, long interruption_code)
{
        if (regs->psw.mask & PSW_MASK_PSTATE) {
            local_irq_enable();
            do_exit(SIGSEGV);
            report_user_fault(interruption_code, regs);
      } else
            die("Unknown program exception", regs, interruption_code);
}

#define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
static void name(struct pt_regs * regs, long interruption_code) \
{ \
        siginfo_t info; \
        info.si_signo = signr; \
        info.si_errno = 0; \
        info.si_code = sicode; \
      info.si_addr = siaddr; \
        do_trap(interruption_code, signr, str, regs, &info); \
}

DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
            ILL_ILLADR, get_check_address(regs))
DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
            ILL_ILLOPN, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
            FPE_INTDIV, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
            FPE_INTOVF, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
            FPE_FLTOVF, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
            FPE_FLTUND, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
            FPE_FLTRES, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
            FPE_FLTDIV, get_check_address(regs))
DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
            FPE_FLTINV, get_check_address(regs))
DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
            ILL_ILLOPN, get_check_address(regs))
DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
            ILL_PRVOPC, get_check_address(regs))
DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
            ILL_ILLOPN, get_check_address(regs))
DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
            ILL_ILLOPN, get_check_address(regs))

static inline void
do_fp_trap(struct pt_regs *regs, void __user *location,
           int fpc, long interruption_code)
{
      siginfo_t si;

      si.si_signo = SIGFPE;
      si.si_errno = 0;
      si.si_addr = location;
      si.si_code = 0;
      /* FPC[2] is Data Exception Code */
      if ((fpc & 0x00000300) == 0) {
            /* bits 6 and 7 of DXC are 0 iff IEEE exception */
            if (fpc & 0x8000) /* invalid fp operation */
                  si.si_code = FPE_FLTINV;
            else if (fpc & 0x4000) /* div by 0 */
                  si.si_code = FPE_FLTDIV;
            else if (fpc & 0x2000) /* overflow */
                  si.si_code = FPE_FLTOVF;
            else if (fpc & 0x1000) /* underflow */
                  si.si_code = FPE_FLTUND;
            else if (fpc & 0x0800) /* inexact */
                  si.si_code = FPE_FLTRES;
      }
      current->thread.ieee_instruction_pointer = (addr_t) location;
      do_trap(interruption_code, SIGFPE,
            "floating point exception", regs, &si);
}

static void illegal_op(struct pt_regs * regs, long interruption_code)
{
      siginfo_t info;
        __u8 opcode[6];
      __u16 __user *location;
      int signal = 0;

      location = get_check_address(regs);

      /*
       * We got all needed information from the lowcore and can
       * now safely switch on interrupts.
       */
      if (regs->psw.mask & PSW_MASK_PSTATE)
            local_irq_enable();

      if (regs->psw.mask & PSW_MASK_PSTATE) {
            if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
                  return;
            if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
                  if (current->ptrace & PT_PTRACED)
                        force_sig(SIGTRAP, current);
                  else
                        signal = SIGILL;
#ifdef CONFIG_MATHEMU
            } else if (opcode[0] == 0xb3) {
                  if (get_user(*((__u16 *) (opcode+2)), location+1))
                        return;
                  signal = math_emu_b3(opcode, regs);
                } else if (opcode[0] == 0xed) {
                  if (get_user(*((__u32 *) (opcode+2)),
                             (__u32 __user *)(location+1)))
                        return;
                  signal = math_emu_ed(opcode, regs);
            } else if (*((__u16 *) opcode) == 0xb299) {
                  if (get_user(*((__u16 *) (opcode+2)), location+1))
                        return;
                  signal = math_emu_srnm(opcode, regs);
            } else if (*((__u16 *) opcode) == 0xb29c) {
                  if (get_user(*((__u16 *) (opcode+2)), location+1))
                        return;
                  signal = math_emu_stfpc(opcode, regs);
            } else if (*((__u16 *) opcode) == 0xb29d) {
                  if (get_user(*((__u16 *) (opcode+2)), location+1))
                        return;
                  signal = math_emu_lfpc(opcode, regs);
#endif
            } else
                  signal = SIGILL;
      } else {
            /*
             * If we get an illegal op in kernel mode, send it through the
             * kprobes notifier. If kprobes doesn't pick it up, SIGILL
             */
            if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
                         3, SIGTRAP) != NOTIFY_STOP)
                  signal = SIGILL;
      }

#ifdef CONFIG_MATHEMU
        if (signal == SIGFPE)
            do_fp_trap(regs, location,
                           current->thread.fp_regs.fpc, interruption_code);
        else if (signal == SIGSEGV) {
            info.si_signo = signal;
            info.si_errno = 0;
            info.si_code = SEGV_MAPERR;
            info.si_addr = (void __user *) location;
            do_trap(interruption_code, signal,
                  "user address fault", regs, &info);
      } else
#endif
        if (signal) {
            info.si_signo = signal;
            info.si_errno = 0;
            info.si_code = ILL_ILLOPC;
            info.si_addr = (void __user *) location;
            do_trap(interruption_code, signal,
                  "illegal operation", regs, &info);
      }
}


#ifdef CONFIG_MATHEMU
asmlinkage void 
specification_exception(struct pt_regs * regs, long interruption_code)
{
        __u8 opcode[6];
      __u16 __user *location = NULL;
      int signal = 0;

      location = (__u16 __user *) get_check_address(regs);

      /*
       * We got all needed information from the lowcore and can
       * now safely switch on interrupts.
       */
        if (regs->psw.mask & PSW_MASK_PSTATE)
            local_irq_enable();

        if (regs->psw.mask & PSW_MASK_PSTATE) {
            get_user(*((__u16 *) opcode), location);
            switch (opcode[0]) {
            case 0x28: /* LDR Rx,Ry   */
                  signal = math_emu_ldr(opcode);
                  break;
            case 0x38: /* LER Rx,Ry   */
                  signal = math_emu_ler(opcode);
                  break;
            case 0x60: /* STD R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_std(opcode, regs);
                  break;
            case 0x68: /* LD R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_ld(opcode, regs);
                  break;
            case 0x70: /* STE R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_ste(opcode, regs);
                  break;
            case 0x78: /* LE R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_le(opcode, regs);
                  break;
            default:
                  signal = SIGILL;
                  break;
                }
        } else
            signal = SIGILL;

        if (signal == SIGFPE)
            do_fp_trap(regs, location,
                           current->thread.fp_regs.fpc, interruption_code);
        else if (signal) {
            siginfo_t info;
            info.si_signo = signal;
            info.si_errno = 0;
            info.si_code = ILL_ILLOPN;
            info.si_addr = location;
            do_trap(interruption_code, signal, 
                  "specification exception", regs, &info);
      }
}
#else
DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
            ILL_ILLOPN, get_check_address(regs));
#endif

static void data_exception(struct pt_regs * regs, long interruption_code)
{
      __u16 __user *location;
      int signal = 0;

      location = get_check_address(regs);

      /*
       * We got all needed information from the lowcore and can
       * now safely switch on interrupts.
       */
      if (regs->psw.mask & PSW_MASK_PSTATE)
            local_irq_enable();

      if (MACHINE_HAS_IEEE)
            asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));

#ifdef CONFIG_MATHEMU
        else if (regs->psw.mask & PSW_MASK_PSTATE) {
            __u8 opcode[6];
            get_user(*((__u16 *) opcode), location);
            switch (opcode[0]) {
            case 0x28: /* LDR Rx,Ry   */
                  signal = math_emu_ldr(opcode);
                  break;
            case 0x38: /* LER Rx,Ry   */
                  signal = math_emu_ler(opcode);
                  break;
            case 0x60: /* STD R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_std(opcode, regs);
                  break;
            case 0x68: /* LD R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_ld(opcode, regs);
                  break;
            case 0x70: /* STE R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_ste(opcode, regs);
                  break;
            case 0x78: /* LE R,D(X,B) */
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_le(opcode, regs);
                  break;
            case 0xb3:
                  get_user(*((__u16 *) (opcode+2)), location+1);
                  signal = math_emu_b3(opcode, regs);
                  break;
                case 0xed:
                  get_user(*((__u32 *) (opcode+2)),
                         (__u32 __user *)(location+1));
                  signal = math_emu_ed(opcode, regs);
                  break;
              case 0xb2:
                  if (opcode[1] == 0x99) {
                        get_user(*((__u16 *) (opcode+2)), location+1);
                        signal = math_emu_srnm(opcode, regs);
                  } else if (opcode[1] == 0x9c) {
                        get_user(*((__u16 *) (opcode+2)), location+1);
                        signal = math_emu_stfpc(opcode, regs);
                  } else if (opcode[1] == 0x9d) {
                        get_user(*((__u16 *) (opcode+2)), location+1);
                        signal = math_emu_lfpc(opcode, regs);
                  } else
                        signal = SIGILL;
                  break;
            default:
                  signal = SIGILL;
                  break;
                }
        }
#endif 
      if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
            signal = SIGFPE;
      else
            signal = SIGILL;
        if (signal == SIGFPE)
            do_fp_trap(regs, location,
                           current->thread.fp_regs.fpc, interruption_code);
        else if (signal) {
            siginfo_t info;
            info.si_signo = signal;
            info.si_errno = 0;
            info.si_code = ILL_ILLOPN;
            info.si_addr = location;
            do_trap(interruption_code, signal, 
                  "data exception", regs, &info);
      }
}

static void space_switch_exception(struct pt_regs * regs, long int_code)
{
        siginfo_t info;

      /* Set user psw back to home space mode. */
      if (regs->psw.mask & PSW_MASK_PSTATE)
            regs->psw.mask |= PSW_ASC_HOME;
      /* Send SIGILL. */
        info.si_signo = SIGILL;
        info.si_errno = 0;
        info.si_code = ILL_PRVOPC;
        info.si_addr = get_check_address(regs);
        do_trap(int_code, SIGILL, "space switch event", regs, &info);
}

asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
{
      bust_spinlocks(1);
      printk("Kernel stack overflow.\n");
      show_regs(regs);
      bust_spinlocks(0);
      panic("Corrupt kernel stack, can't continue.");
}

/* init is done in lowcore.S and head.S */

void __init trap_init(void)
{
        int i;

        for (i = 0; i < 128; i++)
          pgm_check_table[i] = &default_trap_handler;
        pgm_check_table[1] = &illegal_op;
        pgm_check_table[2] = &privileged_op;
        pgm_check_table[3] = &execute_exception;
        pgm_check_table[4] = &do_protection_exception;
        pgm_check_table[5] = &addressing_exception;
        pgm_check_table[6] = &specification_exception;
        pgm_check_table[7] = &data_exception;
        pgm_check_table[8] = &overflow_exception;
        pgm_check_table[9] = &divide_exception;
        pgm_check_table[0x0A] = &overflow_exception;
        pgm_check_table[0x0B] = &divide_exception;
        pgm_check_table[0x0C] = &hfp_overflow_exception;
        pgm_check_table[0x0D] = &hfp_underflow_exception;
        pgm_check_table[0x0E] = &hfp_significance_exception;
        pgm_check_table[0x0F] = &hfp_divide_exception;
        pgm_check_table[0x10] = &do_dat_exception;
        pgm_check_table[0x11] = &do_dat_exception;
        pgm_check_table[0x12] = &translation_exception;
        pgm_check_table[0x13] = &special_op_exception;
#ifdef CONFIG_64BIT
      pgm_check_table[0x38] = &do_asce_exception;
      pgm_check_table[0x39] = &do_dat_exception;
      pgm_check_table[0x3A] = &do_dat_exception;
        pgm_check_table[0x3B] = &do_dat_exception;
#endif /* CONFIG_64BIT */
        pgm_check_table[0x15] = &operand_exception;
        pgm_check_table[0x1C] = &space_switch_exception;
        pgm_check_table[0x1D] = &hfp_sqrt_exception;
      pfault_irq_init();
}

Generated by  Doxygen 1.6.0   Back to index