linux/arch/mn10300/kernel/traps.c
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   1/* MN10300 Exception handling
   2 *
   3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
   4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   5 * Modified by David Howells (dhowells@redhat.com)
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public Licence
   9 * as published by the Free Software Foundation; either version
  10 * 2 of the Licence, or (at your option) any later version.
  11 */
  12#include <linux/sched.h>
  13#include <linux/kernel.h>
  14#include <linux/string.h>
  15#include <linux/errno.h>
  16#include <linux/ptrace.h>
  17#include <linux/timer.h>
  18#include <linux/mm.h>
  19#include <linux/smp.h>
  20#include <linux/smp_lock.h>
  21#include <linux/init.h>
  22#include <linux/delay.h>
  23#include <linux/spinlock.h>
  24#include <linux/interrupt.h>
  25#include <linux/kallsyms.h>
  26#include <linux/pci.h>
  27#include <linux/kdebug.h>
  28#include <linux/bug.h>
  29#include <linux/irq.h>
  30#include <asm/processor.h>
  31#include <asm/system.h>
  32#include <asm/uaccess.h>
  33#include <asm/io.h>
  34#include <asm/atomic.h>
  35#include <asm/smp.h>
  36#include <asm/pgalloc.h>
  37#include <asm/cacheflush.h>
  38#include <asm/cpu-regs.h>
  39#include <asm/busctl-regs.h>
  40#include <asm/unit/leds.h>
  41#include <asm/fpu.h>
  42#include <asm/gdb-stub.h>
  43#include <asm/sections.h>
  44
  45#if (CONFIG_INTERRUPT_VECTOR_BASE & 0xffffff)
  46#error "INTERRUPT_VECTOR_BASE not aligned to 16MiB boundary!"
  47#endif
  48
  49struct pt_regs *__frame; /* current frame pointer */
  50EXPORT_SYMBOL(__frame);
  51
  52int kstack_depth_to_print = 24;
  53
  54spinlock_t die_lock = __SPIN_LOCK_UNLOCKED(die_lock);
  55
  56ATOMIC_NOTIFIER_HEAD(mn10300_die_chain);
  57
  58/*
  59 * These constants are for searching for possible module text
  60 * segments. MODULE_RANGE is a guess of how much space is likely
  61 * to be vmalloced.
  62 */
  63#define MODULE_RANGE (8 * 1024 * 1024)
  64
  65#define DO_ERROR(signr, prologue, str, name)                    \
  66asmlinkage void name(struct pt_regs *regs, u32 intcode)         \
  67{                                                               \
  68        prologue;                                               \
  69        if (die_if_no_fixup(str, regs, intcode))                \
  70                return;                                         \
  71        force_sig(signr, current);                              \
  72}
  73
  74#define DO_EINFO(signr, prologue, str, name, sicode)                    \
  75asmlinkage void name(struct pt_regs *regs, u32 intcode)                 \
  76{                                                                       \
  77        siginfo_t info;                                                 \
  78        prologue;                                                       \
  79        if (die_if_no_fixup(str, regs, intcode))                        \
  80                return;                                                 \
  81        info.si_signo = signr;                                          \
  82        if (signr == SIGILL && sicode == ILL_ILLOPC) {                  \
  83                uint8_t opcode;                                         \
  84                if (get_user(opcode, (uint8_t __user *)regs->pc) == 0)  \
  85                        if (opcode == 0xff)                             \
  86                                info.si_signo = SIGTRAP;                \
  87        }                                                               \
  88        info.si_errno = 0;                                              \
  89        info.si_code = sicode;                                          \
  90        info.si_addr = (void *) regs->pc;                               \
  91        force_sig_info(info.si_signo, &info, current);                  \
  92}
  93
  94DO_ERROR(SIGTRAP, {}, "trap",                   trap);
  95DO_ERROR(SIGSEGV, {}, "ibreak",                 ibreak);
  96DO_ERROR(SIGSEGV, {}, "obreak",                 obreak);
  97DO_EINFO(SIGSEGV, {}, "access error",           access_error,   SEGV_ACCERR);
  98DO_EINFO(SIGSEGV, {}, "insn access error",      insn_acc_error, SEGV_ACCERR);
  99DO_EINFO(SIGSEGV, {}, "data access error",      data_acc_error, SEGV_ACCERR);
 100DO_EINFO(SIGILL,  {}, "privileged opcode",      priv_op,        ILL_PRVOPC);
 101DO_EINFO(SIGILL,  {}, "invalid opcode",         invalid_op,     ILL_ILLOPC);
 102DO_EINFO(SIGILL,  {}, "invalid ex opcode",      invalid_exop,   ILL_ILLOPC);
 103DO_EINFO(SIGBUS,  {}, "invalid address",        mem_error,      BUS_ADRERR);
 104DO_EINFO(SIGBUS,  {}, "bus error",              bus_error,      BUS_ADRERR);
 105DO_EINFO(SIGILL,  {}, "FPU invalid opcode",     fpu_invalid_op, ILL_COPROC);
 106
 107DO_ERROR(SIGTRAP,
 108#ifndef CONFIG_MN10300_USING_JTAG
 109         DCR &= ~0x0001,
 110#else
 111         {},
 112#endif
 113         "single step", istep);
 114
 115/*
 116 * handle NMI
 117 */
 118asmlinkage void nmi(struct pt_regs *regs, enum exception_code code)
 119{
 120        /* see if gdbstub wants to deal with it */
 121#ifdef CONFIG_GDBSTUB
 122        if (gdbstub_intercept(regs, code))
 123                return;
 124#endif
 125
 126        printk(KERN_WARNING "--- Register Dump ---\n");
 127        show_registers(regs);
 128        printk(KERN_WARNING "---------------------\n");
 129}
 130
 131/*
 132 * show a stack trace from the specified stack pointer
 133 */
 134void show_trace(unsigned long *sp)
 135{
 136        unsigned long *stack, addr, module_start, module_end;
 137        int i;
 138
 139        printk(KERN_EMERG "\n"
 140               KERN_EMERG "Call Trace:");
 141
 142        stack = sp;
 143        i = 0;
 144        module_start = VMALLOC_START;
 145        module_end = VMALLOC_END;
 146
 147        while (((long) stack & (THREAD_SIZE - 1)) != 0) {
 148                addr = *stack++;
 149                if (__kernel_text_address(addr)) {
 150#if 1
 151                        printk(" [<%08lx>]", addr);
 152                        print_symbol(" %s", addr);
 153                        printk("\n");
 154#else
 155                        if ((i % 6) == 0)
 156                                printk("\n" KERN_EMERG "  ");
 157                        printk("[<%08lx>] ", addr);
 158                        i++;
 159#endif
 160                }
 161        }
 162
 163        printk("\n");
 164}
 165
 166/*
 167 * show the raw stack from the specified stack pointer
 168 */
 169void show_stack(struct task_struct *task, unsigned long *sp)
 170{
 171        unsigned long *stack;
 172        int i;
 173
 174        if (!sp)
 175                sp = (unsigned long *) &sp;
 176
 177        stack = sp;
 178        printk(KERN_EMERG "Stack:");
 179        for (i = 0; i < kstack_depth_to_print; i++) {
 180                if (((long) stack & (THREAD_SIZE - 1)) == 0)
 181                        break;
 182                if ((i % 8) == 0)
 183                        printk("\n" KERN_EMERG "  ");
 184                printk("%08lx ", *stack++);
 185        }
 186
 187        show_trace(sp);
 188}
 189
 190/*
 191 * the architecture-independent dump_stack generator
 192 */
 193void dump_stack(void)
 194{
 195        unsigned long stack;
 196
 197        show_stack(current, &stack);
 198}
 199EXPORT_SYMBOL(dump_stack);
 200
 201/*
 202 * dump the register file in the specified exception frame
 203 */
 204void show_registers_only(struct pt_regs *regs)
 205{
 206        unsigned long ssp;
 207
 208        ssp = (unsigned long) regs + sizeof(*regs);
 209
 210        printk(KERN_EMERG "PC:  %08lx EPSW:  %08lx  SSP: %08lx mode: %s\n",
 211               regs->pc, regs->epsw, ssp, user_mode(regs) ? "User" : "Super");
 212        printk(KERN_EMERG "d0:  %08lx   d1:  %08lx   d2: %08lx   d3: %08lx\n",
 213               regs->d0, regs->d1, regs->d2, regs->d3);
 214        printk(KERN_EMERG "a0:  %08lx   a1:  %08lx   a2: %08lx   a3: %08lx\n",
 215               regs->a0, regs->a1, regs->a2, regs->a3);
 216        printk(KERN_EMERG "e0:  %08lx   e1:  %08lx   e2: %08lx   e3: %08lx\n",
 217               regs->e0, regs->e1, regs->e2, regs->e3);
 218        printk(KERN_EMERG "e4:  %08lx   e5:  %08lx   e6: %08lx   e7: %08lx\n",
 219               regs->e4, regs->e5, regs->e6, regs->e7);
 220        printk(KERN_EMERG "lar: %08lx   lir: %08lx  mdr: %08lx  usp: %08lx\n",
 221               regs->lar, regs->lir, regs->mdr, regs->sp);
 222        printk(KERN_EMERG "cvf: %08lx   crl: %08lx  crh: %08lx  drq: %08lx\n",
 223               regs->mcvf, regs->mcrl, regs->mcrh, regs->mdrq);
 224        printk(KERN_EMERG "threadinfo=%p task=%p)\n",
 225               current_thread_info(), current);
 226
 227        if ((unsigned long) current >= 0x90000000UL &&
 228            (unsigned long) current < 0x94000000UL)
 229                printk(KERN_EMERG "Process %s (pid: %d)\n",
 230                       current->comm, current->pid);
 231
 232        printk(KERN_EMERG "CPUP:   %04hx\n", CPUP);
 233        printk(KERN_EMERG "TBR:    %08x\n", TBR);
 234        printk(KERN_EMERG "DEAR:   %08x\n", DEAR);
 235        printk(KERN_EMERG "sISR:   %08x\n", sISR);
 236        printk(KERN_EMERG "NMICR:  %04hx\n", NMICR);
 237        printk(KERN_EMERG "BCBERR: %08x\n", BCBERR);
 238        printk(KERN_EMERG "BCBEAR: %08x\n", BCBEAR);
 239        printk(KERN_EMERG "MMUFCR: %08x\n", MMUFCR);
 240        printk(KERN_EMERG "IPTEU : %08x  IPTEL2: %08x\n", IPTEU, IPTEL2);
 241        printk(KERN_EMERG "DPTEU:  %08x  DPTEL2: %08x\n", DPTEU, DPTEL2);
 242}
 243
 244/*
 245 * dump the registers and the stack
 246 */
 247void show_registers(struct pt_regs *regs)
 248{
 249        unsigned long sp;
 250        int i;
 251
 252        show_registers_only(regs);
 253
 254        if (!user_mode(regs))
 255                sp = (unsigned long) regs + sizeof(*regs);
 256        else
 257                sp = regs->sp;
 258
 259        /* when in-kernel, we also print out the stack and code at the
 260         * time of the fault..
 261         */
 262        if (!user_mode(regs)) {
 263                printk(KERN_EMERG "\n");
 264                show_stack(current, (unsigned long *) sp);
 265
 266#if 0
 267                printk(KERN_EMERG "\n"
 268                       KERN_EMERG "Code: ");
 269                if (regs->pc < PAGE_OFFSET)
 270                        goto bad;
 271
 272                for (i = 0; i < 20; i++) {
 273                        unsigned char c;
 274                        if (__get_user(c, &((unsigned char *) regs->pc)[i]))
 275                                goto bad;
 276                        printk("%02x ", c);
 277                }
 278#else
 279                i = 0;
 280#endif
 281        }
 282
 283        printk("\n");
 284        return;
 285
 286#if 0
 287bad:
 288        printk(KERN_EMERG " Bad PC value.");
 289        break;
 290#endif
 291}
 292
 293/*
 294 *
 295 */
 296void show_trace_task(struct task_struct *tsk)
 297{
 298        unsigned long sp = tsk->thread.sp;
 299
 300        /* User space on another CPU? */
 301        if ((sp ^ (unsigned long) tsk) & (PAGE_MASK << 1))
 302                return;
 303
 304        show_trace((unsigned long *) sp);
 305}
 306
 307/*
 308 * note the untimely death of part of the kernel
 309 */
 310void die(const char *str, struct pt_regs *regs, enum exception_code code)
 311{
 312        console_verbose();
 313        spin_lock_irq(&die_lock);
 314        printk(KERN_EMERG "\n"
 315               KERN_EMERG "%s: %04x\n",
 316               str, code & 0xffff);
 317        show_registers(regs);
 318
 319        if (regs->pc >= 0x02000000 && regs->pc < 0x04000000 &&
 320            (regs->epsw & (EPSW_IM | EPSW_IE)) != (EPSW_IM | EPSW_IE)) {
 321                printk(KERN_EMERG "Exception in usermode interrupt handler\n");
 322                printk(KERN_EMERG "\n"
 323                       KERN_EMERG "  Please connect to kernel debugger !!\n");
 324                asm volatile ("0: bra 0b");
 325        }
 326
 327        spin_unlock_irq(&die_lock);
 328        do_exit(SIGSEGV);
 329}
 330
 331/*
 332 * see if there's a fixup handler we can force a jump to when an exception
 333 * happens due to something kernel code did
 334 */
 335int die_if_no_fixup(const char *str, struct pt_regs *regs,
 336                    enum exception_code code)
 337{
 338        if (user_mode(regs))
 339                return 0;
 340
 341        peripheral_leds_display_exception(code);
 342
 343        switch (code) {
 344                /* see if we can fixup the kernel accessing memory */
 345        case EXCEP_ITLBMISS:
 346        case EXCEP_DTLBMISS:
 347        case EXCEP_IAERROR:
 348        case EXCEP_DAERROR:
 349        case EXCEP_MEMERR:
 350        case EXCEP_MISALIGN:
 351        case EXCEP_BUSERROR:
 352        case EXCEP_ILLDATACC:
 353        case EXCEP_IOINSACC:
 354        case EXCEP_PRIVINSACC:
 355        case EXCEP_PRIVDATACC:
 356        case EXCEP_DATINSACC:
 357                if (fixup_exception(regs))
 358                        return 1;
 359        case EXCEP_UNIMPINS:
 360                if (regs->pc && *(uint8_t *)regs->pc == 0xff)
 361                        if (notify_die(DIE_BREAKPOINT, str, regs, code, 0, 0))
 362                                return 1;
 363                break;
 364        default:
 365                break;
 366        }
 367
 368        /* see if gdbstub wants to deal with it */
 369#ifdef CONFIG_GDBSTUB
 370        if (gdbstub_intercept(regs, code))
 371                return 1;
 372#endif
 373
 374        if (notify_die(DIE_GPF, str, regs, code, 0, 0))
 375                return 1;
 376
 377        /* make the process die as the last resort */
 378        die(str, regs, code);
 379}
 380
 381/*
 382 * handle unsupported syscall instructions (syscall 1-15)
 383 */
 384static asmlinkage void unsupported_syscall(struct pt_regs *regs,
 385                                           enum exception_code code)
 386{
 387        struct task_struct *tsk = current;
 388        siginfo_t info;
 389
 390        /* catch a kernel BUG() */
 391        if (code == EXCEP_SYSCALL15 && !user_mode(regs)) {
 392                if (report_bug(regs->pc, regs) == BUG_TRAP_TYPE_BUG) {
 393#ifdef CONFIG_GDBSTUB
 394                        gdbstub_intercept(regs, code);
 395#endif
 396                }
 397        }
 398
 399        regs->pc -= 2; /* syscall return addr is _after_ the instruction */
 400
 401        die_if_no_fixup("An unsupported syscall insn was used by the kernel\n",
 402                        regs, code);
 403
 404        info.si_signo   = SIGILL;
 405        info.si_errno   = ENOSYS;
 406        info.si_code    = ILL_ILLTRP;
 407        info.si_addr    = (void *) regs->pc;
 408        force_sig_info(SIGILL, &info, tsk);
 409}
 410
 411/*
 412 * display the register file when the stack pointer gets clobbered
 413 */
 414asmlinkage void do_double_fault(struct pt_regs *regs)
 415{
 416        struct task_struct *tsk = current;
 417
 418        strcpy(tsk->comm, "emergency tsk");
 419        tsk->pid = 0;
 420        console_verbose();
 421        printk(KERN_EMERG "--- double fault ---\n");
 422        show_registers(regs);
 423}
 424
 425/*
 426 * asynchronous bus error (external, usually I/O DMA)
 427 */
 428asmlinkage void io_bus_error(u32 bcberr, u32 bcbear, struct pt_regs *regs)
 429{
 430        console_verbose();
 431
 432        printk(KERN_EMERG "\n"
 433               KERN_EMERG "Asynchronous I/O Bus Error\n"
 434               KERN_EMERG "==========================\n");
 435
 436        if (bcberr & BCBERR_BEME)
 437                printk(KERN_EMERG "- Multiple recorded errors\n");
 438
 439        printk(KERN_EMERG "- Faulting Buses:%s%s%s\n",
 440               bcberr & BCBERR_BEMR_CI  ? " CPU-Ins-Fetch" : "",
 441               bcberr & BCBERR_BEMR_CD  ? " CPU-Data" : "",
 442               bcberr & BCBERR_BEMR_DMA ? " DMA" : "");
 443
 444        printk(KERN_EMERG "- %s %s access made to %s at address %08x\n",
 445               bcberr & BCBERR_BEBST ? "Burst" : "Single",
 446               bcberr & BCBERR_BERW ? "Read" : "Write",
 447               bcberr & BCBERR_BESB_MON  ? "Monitor Space" :
 448               bcberr & BCBERR_BESB_IO   ? "Internal CPU I/O Space" :
 449               bcberr & BCBERR_BESB_EX   ? "External I/O Bus" :
 450               bcberr & BCBERR_BESB_OPEX ? "External Memory Bus" :
 451               "On Chip Memory",
 452               bcbear
 453               );
 454
 455        printk(KERN_EMERG "- Detected by the %s\n",
 456               bcberr&BCBERR_BESD ? "Bus Control Unit" : "Slave Bus");
 457
 458#ifdef CONFIG_PCI
 459#define BRIDGEREGB(X) (*(volatile __u8  *)(0xBE040000 + (X)))
 460#define BRIDGEREGW(X) (*(volatile __u16 *)(0xBE040000 + (X)))
 461#define BRIDGEREGL(X) (*(volatile __u32 *)(0xBE040000 + (X)))
 462
 463        printk(KERN_EMERG "- PCI Memory Paging Reg:         %08x\n",
 464               *(volatile __u32 *) (0xBFFFFFF4));
 465        printk(KERN_EMERG "- PCI Bridge Base Address 0:     %08x\n",
 466               BRIDGEREGL(PCI_BASE_ADDRESS_0));
 467        printk(KERN_EMERG "- PCI Bridge AMPCI Base Address: %08x\n",
 468               BRIDGEREGL(0x48));
 469        printk(KERN_EMERG "- PCI Bridge Command:                %04hx\n",
 470               BRIDGEREGW(PCI_COMMAND));
 471        printk(KERN_EMERG "- PCI Bridge Status:                 %04hx\n",
 472               BRIDGEREGW(PCI_STATUS));
 473        printk(KERN_EMERG "- PCI Bridge Int Status:         %08hx\n",
 474               BRIDGEREGL(0x4c));
 475#endif
 476
 477        printk(KERN_EMERG "\n");
 478        show_registers(regs);
 479
 480        panic("Halted due to asynchronous I/O Bus Error\n");
 481}
 482
 483/*
 484 * handle an exception for which a handler has not yet been installed
 485 */
 486asmlinkage void uninitialised_exception(struct pt_regs *regs,
 487                                        enum exception_code code)
 488{
 489
 490        /* see if gdbstub wants to deal with it */
 491#ifdef CONFIG_GDBSTUB
 492        if (gdbstub_intercept(regs, code))
 493                return;
 494#endif
 495
 496        peripheral_leds_display_exception(code);
 497        printk(KERN_EMERG "Uninitialised Exception 0x%04x\n", code & 0xFFFF);
 498        show_registers(regs);
 499
 500        for (;;)
 501                continue;
 502}
 503
 504/*
 505 * set an interrupt stub to jump to a handler
 506 * ! NOTE: this does *not* flush the caches
 507 */
 508void __init __set_intr_stub(enum exception_code code, void *handler)
 509{
 510        unsigned long addr;
 511        u8 *vector = (u8 *)(CONFIG_INTERRUPT_VECTOR_BASE + code);
 512
 513        addr = (unsigned long) handler - (unsigned long) vector;
 514        vector[0] = 0xdc;               /* JMP handler */
 515        vector[1] = addr;
 516        vector[2] = addr >> 8;
 517        vector[3] = addr >> 16;
 518        vector[4] = addr >> 24;
 519        vector[5] = 0xcb;
 520        vector[6] = 0xcb;
 521        vector[7] = 0xcb;
 522}
 523
 524/*
 525 * set an interrupt stub to jump to a handler
 526 */
 527void __init set_intr_stub(enum exception_code code, void *handler)
 528{
 529        unsigned long addr;
 530        u8 *vector = (u8 *)(CONFIG_INTERRUPT_VECTOR_BASE + code);
 531
 532        addr = (unsigned long) handler - (unsigned long) vector;
 533        vector[0] = 0xdc;               /* JMP handler */
 534        vector[1] = addr;
 535        vector[2] = addr >> 8;
 536        vector[3] = addr >> 16;
 537        vector[4] = addr >> 24;
 538        vector[5] = 0xcb;
 539        vector[6] = 0xcb;
 540        vector[7] = 0xcb;
 541
 542        mn10300_dcache_flush_inv();
 543        mn10300_icache_inv();
 544}
 545
 546/*
 547 * set an interrupt stub to invoke the JTAG unit and then jump to a handler
 548 */
 549void __init set_jtag_stub(enum exception_code code, void *handler)
 550{
 551        unsigned long addr;
 552        u8 *vector = (u8 *)(CONFIG_INTERRUPT_VECTOR_BASE + code);
 553
 554        addr = (unsigned long) handler - ((unsigned long) vector + 1);
 555        vector[0] = 0xff;               /* PI to jump into JTAG debugger */
 556        vector[1] = 0xdc;               /* jmp handler */
 557        vector[2] = addr;
 558        vector[3] = addr >> 8;
 559        vector[4] = addr >> 16;
 560        vector[5] = addr >> 24;
 561        vector[6] = 0xcb;
 562        vector[7] = 0xcb;
 563
 564        mn10300_dcache_flush_inv();
 565        flush_icache_range((unsigned long) vector, (unsigned long) vector + 8);
 566}
 567
 568/*
 569 * initialise the exception table
 570 */
 571void __init trap_init(void)
 572{
 573        set_excp_vector(EXCEP_TRAP,             trap);
 574        set_excp_vector(EXCEP_ISTEP,            istep);
 575        set_excp_vector(EXCEP_IBREAK,           ibreak);
 576        set_excp_vector(EXCEP_OBREAK,           obreak);
 577
 578        set_excp_vector(EXCEP_PRIVINS,          priv_op);
 579        set_excp_vector(EXCEP_UNIMPINS,         invalid_op);
 580        set_excp_vector(EXCEP_UNIMPEXINS,       invalid_exop);
 581        set_excp_vector(EXCEP_MEMERR,           mem_error);
 582        set_excp_vector(EXCEP_MISALIGN,         misalignment);
 583        set_excp_vector(EXCEP_BUSERROR,         bus_error);
 584        set_excp_vector(EXCEP_ILLINSACC,        insn_acc_error);
 585        set_excp_vector(EXCEP_ILLDATACC,        data_acc_error);
 586        set_excp_vector(EXCEP_IOINSACC,         insn_acc_error);
 587        set_excp_vector(EXCEP_PRIVINSACC,       insn_acc_error);
 588        set_excp_vector(EXCEP_PRIVDATACC,       data_acc_error);
 589        set_excp_vector(EXCEP_DATINSACC,        insn_acc_error);
 590        set_excp_vector(EXCEP_FPU_DISABLED,     fpu_disabled);
 591        set_excp_vector(EXCEP_FPU_UNIMPINS,     fpu_invalid_op);
 592        set_excp_vector(EXCEP_FPU_OPERATION,    fpu_exception);
 593
 594        set_excp_vector(EXCEP_NMI,              nmi);
 595
 596        set_excp_vector(EXCEP_SYSCALL1,         unsupported_syscall);
 597        set_excp_vector(EXCEP_SYSCALL2,         unsupported_syscall);
 598        set_excp_vector(EXCEP_SYSCALL3,         unsupported_syscall);
 599        set_excp_vector(EXCEP_SYSCALL4,         unsupported_syscall);
 600        set_excp_vector(EXCEP_SYSCALL5,         unsupported_syscall);
 601        set_excp_vector(EXCEP_SYSCALL6,         unsupported_syscall);
 602        set_excp_vector(EXCEP_SYSCALL7,         unsupported_syscall);
 603        set_excp_vector(EXCEP_SYSCALL8,         unsupported_syscall);
 604        set_excp_vector(EXCEP_SYSCALL9,         unsupported_syscall);
 605        set_excp_vector(EXCEP_SYSCALL10,        unsupported_syscall);
 606        set_excp_vector(EXCEP_SYSCALL11,        unsupported_syscall);
 607        set_excp_vector(EXCEP_SYSCALL12,        unsupported_syscall);
 608        set_excp_vector(EXCEP_SYSCALL13,        unsupported_syscall);
 609        set_excp_vector(EXCEP_SYSCALL14,        unsupported_syscall);
 610        set_excp_vector(EXCEP_SYSCALL15,        unsupported_syscall);
 611}
 612
 613/*
 614 * determine if a program counter value is a valid bug address
 615 */
 616int is_valid_bugaddr(unsigned long pc)
 617{
 618        return pc >= PAGE_OFFSET;
 619}
 620