arch/mn10300/kernel/traps.c

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