arch/s390/kernel/traps.c

   1 /*
   2  *  arch/s390/kernel/traps.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7  *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   8  *
   9  *  Derived from "arch/i386/kernel/traps.c"
  10  *    Copyright (C) 1991, 1992 Linus Torvalds
  11  */
  12
  13 /*
  14  * 'Traps.c' handles hardware traps and faults after we have saved some
  15  * state in 'asm.s'.
  16  */
  17 #include <linux/config.h>
  18 #include <linux/sched.h>
  19 #include <linux/kernel.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/ptrace.h>
  23 #include <linux/timer.h>
  24 #include <linux/mm.h>
  25 #include <linux/smp.h>
  26 #include <linux/smp_lock.h>
  27 #include <linux/init.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/delay.h>
  30 #include <linux/module.h>
  31 #include <linux/kallsyms.h>
  32
  33 #include <asm/system.h>
  34 #include <asm/uaccess.h>
  35 #include <asm/io.h>
  36 #include <asm/atomic.h>
  37 #include <asm/mathemu.h>
  38 #include <asm/cpcmd.h>
  39 #include <asm/s390_ext.h>
  40 #include <asm/lowcore.h>
  41
  42 /* Called from entry.S only */
  43 extern void handle_per_exception(struct pt_regs *regs);
  44
  45 typedef void pgm_check_handler_t(struct pt_regs *, long);
  46 pgm_check_handler_t *pgm_check_table[128];
  47
  48 #ifdef CONFIG_SYSCTL
  49 #ifdef CONFIG_PROCESS_DEBUG
  50 int sysctl_userprocess_debug = 1;
  51 #else
  52 int sysctl_userprocess_debug = 0;
  53 #endif
  54 #endif
  55
  56 extern pgm_check_handler_t do_protection_exception;
  57 extern pgm_check_handler_t do_dat_exception;
  58 extern pgm_check_handler_t do_pseudo_page_fault;
  59 #ifdef CONFIG_PFAULT
  60 extern int pfault_init(void);
  61 extern void pfault_fini(void);
  62 extern void pfault_interrupt(struct pt_regs *regs, __u16 error_code);
  63 static ext_int_info_t ext_int_pfault;
  64 #endif
  65 extern pgm_check_handler_t do_monitor_call;
  66
  67 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
  68
  69 #ifndef CONFIG_ARCH_S390X
  70 #define RET_ADDR 56
  71 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
  72 static int kstack_depth_to_print = 12;
  73
  74 #else /* CONFIG_ARCH_S390X */
  75 #define RET_ADDR 112
  76 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  77 static int kstack_depth_to_print = 20;
  78
  79 #endif /* CONFIG_ARCH_S390X */
  80
  81 void show_trace(struct task_struct *task, unsigned long * stack)
  82 {
  83         unsigned long backchain, low_addr, high_addr, ret_addr;
  84
  85         if (!stack)
  86                 stack = (task == NULL) ? *stack_pointer : &(task->thread.ksp);
  87
  88         printk("Call Trace:\n");
  89         low_addr = ((unsigned long) stack) & PSW_ADDR_INSN;
  90         high_addr = (low_addr & (-THREAD_SIZE)) + THREAD_SIZE;
  91         /* Skip the first frame (biased stack) */
  92         backchain = *((unsigned long *) low_addr) & PSW_ADDR_INSN;
  93         /* Print up to 8 lines */
  94         while  (backchain > low_addr && backchain <= high_addr) {
  95                 ret_addr = *((unsigned long *) (backchain+RET_ADDR)) & PSW_ADDR_INSN;
  96                 printk(" [<%016lx>] ", ret_addr);
  97                 print_symbol("%s\n", ret_addr);
  98                 low_addr = backchain;
  99                 backchain = *((unsigned long *) backchain) & PSW_ADDR_INSN;
 100         }
 101         printk("\n");
 102 }
 103
 104 void show_stack(struct task_struct *task, unsigned long *sp)
 105 {
 106         unsigned long *stack;
 107         int i;
 108
 109         // debugging aid: "show_stack(NULL);" prints the
 110         // back trace for this cpu.
 111
 112         if (!sp) {
 113                 if (task)
 114                         sp = (unsigned long *) task->thread.ksp;
 115                 else
 116                         sp = *stack_pointer;
 117         }
 118
 119         stack = sp;
 120         for (i = 0; i < kstack_depth_to_print; i++) {
 121                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 122                         break;
 123                 if (i && ((i * sizeof (long) % 32) == 0))
 124                         printk("\n       ");
 125                 printk("%p ", (void *)*stack++);
 126         }
 127         printk("\n");
 128         show_trace(task, sp);
 129 }
 130
 131 /*
 132  * The architecture-independent dump_stack generator
 133  */
 134 void dump_stack(void)
 135 {
 136         show_stack(0, 0);
 137 }
 138
 139 EXPORT_SYMBOL(dump_stack);
 140
 141 void show_registers(struct pt_regs *regs)
 142 {
 143         mm_segment_t old_fs;
 144         char *mode;
 145         int i;
 146
 147         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 148         printk("%s PSW : %p %p",
 149                mode, (void *) regs->psw.mask,
 150                (void *) regs->psw.addr);
 151         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 152         printk("%s GPRS: " FOURLONG, mode,
 153                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 154         printk("           " FOURLONG,
 155                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 156         printk("           " FOURLONG,
 157                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 158         printk("           " FOURLONG,
 159                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 160
 161 #if 0
 162         /* FIXME: this isn't needed any more but it changes the ksymoops
 163          * input. To remove or not to remove ... */
 164         save_access_regs(regs->acrs);
 165         printk("%s ACRS: %08x %08x %08x %08x\n", mode,
 166                regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
 167         printk("           %08x %08x %08x %08x\n",
 168                regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
 169         printk("           %08x %08x %08x %08x\n",
 170                regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
 171         printk("           %08x %08x %08x %08x\n",
 172                regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
 173 #endif
 174
 175         /*
 176          * Print the first 20 byte of the instruction stream at the
 177          * time of the fault.
 178          */
 179         old_fs = get_fs();
 180         if (regs->psw.mask & PSW_MASK_PSTATE)
 181                 set_fs(USER_DS);
 182         else
 183                 set_fs(KERNEL_DS);
 184         printk("%s Code: ", mode);
 185         for (i = 0; i < 20; i++) {
 186                 unsigned char c;
 187                 if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
 188                         printk(" Bad PSW.");
 189                         break;
 190                 }
 191                 printk("%02x ", c);
 192         }
 193         set_fs(old_fs);
 194
 195         printk("\n");
 196 }
 197
 198 /* This is called from fs/proc/array.c */
 199 char *task_show_regs(struct task_struct *task, char *buffer)
 200 {
 201         struct pt_regs *regs;
 202
 203         regs = __KSTK_PTREGS(task);
 204         buffer += sprintf(buffer, "task: %p, ksp: %p\n",
 205                        task, (void *)task->thread.ksp);
 206         buffer += sprintf(buffer, "User PSW : %p %p\n",
 207                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 208
 209         buffer += sprintf(buffer, "User GPRS: " FOURLONG,
 210                           regs->gprs[0], regs->gprs[1],
 211                           regs->gprs[2], regs->gprs[3]);
 212         buffer += sprintf(buffer, "           " FOURLONG,
 213                           regs->gprs[4], regs->gprs[5],
 214                           regs->gprs[6], regs->gprs[7]);
 215         buffer += sprintf(buffer, "           " FOURLONG,
 216                           regs->gprs[8], regs->gprs[9],
 217                           regs->gprs[10], regs->gprs[11]);
 218         buffer += sprintf(buffer, "           " FOURLONG,
 219                           regs->gprs[12], regs->gprs[13],
 220                           regs->gprs[14], regs->gprs[15]);
 221         buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
 222                           task->thread.acrs[0], task->thread.acrs[1],
 223                           task->thread.acrs[2], task->thread.acrs[3]);
 224         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 225                           task->thread.acrs[4], task->thread.acrs[5],
 226                           task->thread.acrs[6], task->thread.acrs[7]);
 227         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 228                           task->thread.acrs[8], task->thread.acrs[9],
 229                           task->thread.acrs[10], task->thread.acrs[11]);
 230         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 231                           task->thread.acrs[12], task->thread.acrs[13],
 232                           task->thread.acrs[14], task->thread.acrs[15]);
 233         return buffer;
 234 }
 235
 236 spinlock_t die_lock = SPIN_LOCK_UNLOCKED;
 237
 238 void die(const char * str, struct pt_regs * regs, long err)
 239 {
 240         static int die_counter;
 241         console_verbose();
 242         spin_lock_irq(&die_lock);
 243         bust_spinlocks(1);
 244         printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 245         show_regs(regs);
 246         bust_spinlocks(0);
 247         spin_unlock_irq(&die_lock);
 248         if (in_interrupt())
 249                 panic("Fatal exception in interrupt");
 250         if (panic_on_oops)
 251                 panic("Fatal exception: panic_on_oops");
 252         do_exit(SIGSEGV);
 253 }
 254
 255 static void inline do_trap(long interruption_code, int signr, char *str,
 256                            struct pt_regs *regs, siginfo_t *info)
 257 {
 258         /*
 259          * We got all needed information from the lowcore and can
 260          * now safely switch on interrupts.
 261          */
 262         if (regs->psw.mask & PSW_MASK_PSTATE)
 263                 local_irq_enable();
 264
 265         if (regs->psw.mask & PSW_MASK_PSTATE) {
 266                 struct task_struct *tsk = current;
 267
 268                 tsk->thread.trap_no = interruption_code & 0xffff;
 269                 if (info)
 270                         force_sig_info(signr, info, tsk);
 271                 else
 272                         force_sig(signr, tsk);
 273 #ifndef CONFIG_SYSCTL
 274 #ifdef CONFIG_PROCESS_DEBUG
 275                 printk("User process fault: interruption code 0x%lX\n",
 276                        interruption_code);
 277                 show_regs(regs);
 278 #endif
 279 #else
 280                 if (sysctl_userprocess_debug) {
 281                         printk("User process fault: interruption code 0x%lX\n",
 282                                interruption_code);
 283                         show_regs(regs);
 284                 }
 285 #endif
 286         } else {
 287                 const struct exception_table_entry *fixup;
 288                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 289                 if (fixup)
 290                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 291                 else
 292                         die(str, regs, interruption_code);
 293         }
 294 }
 295
 296 static inline void *get_check_address(struct pt_regs *regs)
 297 {
 298         return (void *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 299 }
 300
 301 void do_single_step(struct pt_regs *regs)
 302 {
 303         if ((current->ptrace & PT_PTRACED) != 0)
 304                 force_sig(SIGTRAP, current);
 305 }
 306
 307 #define DO_ERROR(signr, str, name) \
 308 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
 309 { \
 310         do_trap(interruption_code, signr, str, regs, NULL); \
 311 }
 312
 313 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 314 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
 315 { \
 316         siginfo_t info; \
 317         info.si_signo = signr; \
 318         info.si_errno = 0; \
 319         info.si_code = sicode; \
 320         info.si_addr = (void *)siaddr; \
 321         do_trap(interruption_code, signr, str, regs, &info); \
 322 }
 323
 324 DO_ERROR(SIGSEGV, "Unknown program exception", default_trap_handler)
 325
 326 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 327               ILL_ILLADR, get_check_address(regs))
 328 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 329               ILL_ILLOPN, get_check_address(regs))
 330 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 331               FPE_INTDIV, get_check_address(regs))
 332 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 333               FPE_INTOVF, get_check_address(regs))
 334 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 335               FPE_FLTOVF, get_check_address(regs))
 336 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 337               FPE_FLTUND, get_check_address(regs))
 338 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 339               FPE_FLTRES, get_check_address(regs))
 340 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 341               FPE_FLTDIV, get_check_address(regs))
 342 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 343               FPE_FLTINV, get_check_address(regs))
 344 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 345               ILL_ILLOPN, get_check_address(regs))
 346 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 347               ILL_PRVOPC, get_check_address(regs))
 348 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 349               ILL_ILLOPN, get_check_address(regs))
 350 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 351               ILL_ILLOPN, get_check_address(regs))
 352
 353 static inline void
 354 do_fp_trap(struct pt_regs *regs, void *location,
 355            int fpc, long interruption_code)
 356 {
 357         siginfo_t si;
 358
 359         si.si_signo = SIGFPE;
 360         si.si_errno = 0;
 361         si.si_addr = location;
 362         si.si_code = 0;
 363         /* FPC[2] is Data Exception Code */
 364         if ((fpc & 0x00000300) == 0) {
 365                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 366                 if (fpc & 0x8000) /* invalid fp operation */
 367                         si.si_code = FPE_FLTINV;
 368                 else if (fpc & 0x4000) /* div by 0 */
 369                         si.si_code = FPE_FLTDIV;
 370                 else if (fpc & 0x2000) /* overflow */
 371                         si.si_code = FPE_FLTOVF;
 372                 else if (fpc & 0x1000) /* underflow */
 373                         si.si_code = FPE_FLTUND;
 374                 else if (fpc & 0x0800) /* inexact */
 375                         si.si_code = FPE_FLTRES;
 376         }
 377         current->thread.ieee_instruction_pointer = (addr_t) location;
 378         do_trap(interruption_code, SIGFPE,
 379                 "floating point exception", regs, &si);
 380 }
 381
 382 asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
 383 {
 384         __u8 opcode[6];
 385         __u16 *location;
 386         int signal = 0;
 387
 388         location = (__u16 *) get_check_address(regs);
 389
 390         /*
 391          * We got all needed information from the lowcore and can
 392          * now safely switch on interrupts.
 393          */
 394         if (regs->psw.mask & PSW_MASK_PSTATE)
 395                 local_irq_enable();
 396
 397         if (regs->psw.mask & PSW_MASK_PSTATE) {
 398                 get_user(*((__u16 *) opcode), (__u16 __user *) location);
 399                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 400                         if (current->ptrace & PT_PTRACED)
 401                                 force_sig(SIGTRAP, current);
 402                         else
 403                                 signal = SIGILL;
 404 #ifdef CONFIG_MATHEMU
 405                 } else if (opcode[0] == 0xb3) {
 406                         get_user(*((__u16 *) (opcode+2)), location+1);
 407                         signal = math_emu_b3(opcode, regs);
 408                 } else if (opcode[0] == 0xed) {
 409                         get_user(*((__u32 *) (opcode+2)),
 410                                  (__u32 *)(location+1));
 411                         signal = math_emu_ed(opcode, regs);
 412                 } else if (*((__u16 *) opcode) == 0xb299) {
 413                         get_user(*((__u16 *) (opcode+2)), location+1);
 414                         signal = math_emu_srnm(opcode, regs);
 415                 } else if (*((__u16 *) opcode) == 0xb29c) {
 416                         get_user(*((__u16 *) (opcode+2)), location+1);
 417                         signal = math_emu_stfpc(opcode, regs);
 418                 } else if (*((__u16 *) opcode) == 0xb29d) {
 419                         get_user(*((__u16 *) (opcode+2)), location+1);
 420                         signal = math_emu_lfpc(opcode, regs);
 421 #endif
 422                 } else
 423                         signal = SIGILL;
 424         } else
 425                 signal = SIGILL;
 426
 427         if (signal == SIGFPE)
 428                 do_fp_trap(regs, location,
 429                            current->thread.fp_regs.fpc, interruption_code);
 430         else if (signal)
 431                 do_trap(interruption_code, signal,
 432                         "illegal operation", regs, NULL);
 433 }
 434
 435
 436 #ifdef CONFIG_MATHEMU
 437 asmlinkage void
 438 specification_exception(struct pt_regs * regs, long interruption_code)
 439 {
 440         __u8 opcode[6];
 441         __u16 *location = NULL;
 442         int signal = 0;
 443
 444         location = (__u16 *) get_check_address(regs);
 445
 446         /*
 447          * We got all needed information from the lowcore and can
 448          * now safely switch on interrupts.
 449          */
 450         if (regs->psw.mask & PSW_MASK_PSTATE)
 451                 local_irq_enable();
 452
 453         if (regs->psw.mask & PSW_MASK_PSTATE) {
 454                 get_user(*((__u16 *) opcode), location);
 455                 switch (opcode[0]) {
 456                 case 0x28: /* LDR Rx,Ry   */
 457                         signal = math_emu_ldr(opcode);
 458                         break;
 459                 case 0x38: /* LER Rx,Ry   */
 460                         signal = math_emu_ler(opcode);
 461                         break;
 462                 case 0x60: /* STD R,D(X,B) */
 463                         get_user(*((__u16 *) (opcode+2)), location+1);
 464                         signal = math_emu_std(opcode, regs);
 465                         break;
 466                 case 0x68: /* LD R,D(X,B) */
 467                         get_user(*((__u16 *) (opcode+2)), location+1);
 468                         signal = math_emu_ld(opcode, regs);
 469                         break;
 470                 case 0x70: /* STE R,D(X,B) */
 471                         get_user(*((__u16 *) (opcode+2)), location+1);
 472                         signal = math_emu_ste(opcode, regs);
 473                         break;
 474                 case 0x78: /* LE R,D(X,B) */
 475                         get_user(*((__u16 *) (opcode+2)), location+1);
 476                         signal = math_emu_le(opcode, regs);
 477                         break;
 478                 default:
 479                         signal = SIGILL;
 480                         break;
 481                 }
 482         } else
 483                 signal = SIGILL;
 484
 485         if (signal == SIGFPE)
 486                 do_fp_trap(regs, location,
 487                            current->thread.fp_regs.fpc, interruption_code);
 488         else if (signal) {
 489                 siginfo_t info;
 490                 info.si_signo = signal;
 491                 info.si_errno = 0;
 492                 info.si_code = ILL_ILLOPN;
 493                 info.si_addr = location;
 494                 do_trap(interruption_code, signal,
 495                         "specification exception", regs, &info);
 496         }
 497 }
 498 #else
 499 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 500               ILL_ILLOPN, get_check_address(regs));
 501 #endif
 502
 503 asmlinkage void data_exception(struct pt_regs * regs, long interruption_code)
 504 {
 505         __u16 *location;
 506         int signal = 0;
 507
 508         location = (__u16 *) get_check_address(regs);
 509
 510         /*
 511          * We got all needed information from the lowcore and can
 512          * now safely switch on interrupts.
 513          */
 514         if (regs->psw.mask & PSW_MASK_PSTATE)
 515                 local_irq_enable();
 516
 517         if (MACHINE_HAS_IEEE)
 518                 __asm__ volatile ("stfpc %0\n\t"
 519                                   : "=m" (current->thread.fp_regs.fpc));
 520
 521 #ifdef CONFIG_MATHEMU
 522         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 523                 __u8 opcode[6];
 524                 get_user(*((__u16 *) opcode), location);
 525                 switch (opcode[0]) {
 526                 case 0x28: /* LDR Rx,Ry   */
 527                         signal = math_emu_ldr(opcode);
 528                         break;
 529                 case 0x38: /* LER Rx,Ry   */
 530                         signal = math_emu_ler(opcode);
 531                         break;
 532                 case 0x60: /* STD R,D(X,B) */
 533                         get_user(*((__u16 *) (opcode+2)), location+1);
 534                         signal = math_emu_std(opcode, regs);
 535                         break;
 536                 case 0x68: /* LD R,D(X,B) */
 537                         get_user(*((__u16 *) (opcode+2)), location+1);
 538                         signal = math_emu_ld(opcode, regs);
 539                         break;
 540                 case 0x70: /* STE R,D(X,B) */
 541                         get_user(*((__u16 *) (opcode+2)), location+1);
 542                         signal = math_emu_ste(opcode, regs);
 543                         break;
 544                 case 0x78: /* LE R,D(X,B) */
 545                         get_user(*((__u16 *) (opcode+2)), location+1);
 546                         signal = math_emu_le(opcode, regs);
 547                         break;
 548                 case 0xb3:
 549                         get_user(*((__u16 *) (opcode+2)), location+1);
 550                         signal = math_emu_b3(opcode, regs);
 551                         break;
 552                 case 0xed:
 553                         get_user(*((__u32 *) (opcode+2)),
 554                                  (__u32 *)(location+1));
 555                         signal = math_emu_ed(opcode, regs);
 556                         break;
 557                 case 0xb2:
 558                         if (opcode[1] == 0x99) {
 559                                 get_user(*((__u16 *) (opcode+2)), location+1);
 560                                 signal = math_emu_srnm(opcode, regs);
 561                         } else if (opcode[1] == 0x9c) {
 562                                 get_user(*((__u16 *) (opcode+2)), location+1);
 563                                 signal = math_emu_stfpc(opcode, regs);
 564                         } else if (opcode[1] == 0x9d) {
 565                                 get_user(*((__u16 *) (opcode+2)), location+1);
 566                                 signal = math_emu_lfpc(opcode, regs);
 567                         } else
 568                                 signal = SIGILL;
 569                         break;
 570                 default:
 571                         signal = SIGILL;
 572                         break;
 573                 }
 574         }
 575 #endif
 576         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 577                 signal = SIGFPE;
 578         else
 579                 signal = SIGILL;
 580         if (signal == SIGFPE)
 581                 do_fp_trap(regs, location,
 582                            current->thread.fp_regs.fpc, interruption_code);
 583         else if (signal) {
 584                 siginfo_t info;
 585                 info.si_signo = signal;
 586                 info.si_errno = 0;
 587                 info.si_code = ILL_ILLOPN;
 588                 info.si_addr = location;
 589                 do_trap(interruption_code, signal,
 590                         "data exception", regs, &info);
 591         }
 592 }
 593
 594
 595
 596 /* init is done in lowcore.S and head.S */
 597
 598 void __init trap_init(void)
 599 {
 600         int i;
 601
 602         for (i = 0; i < 128; i++)
 603           pgm_check_table[i] = &default_trap_handler;
 604         pgm_check_table[1] = &illegal_op;
 605         pgm_check_table[2] = &privileged_op;
 606         pgm_check_table[3] = &execute_exception;
 607         pgm_check_table[4] = &do_protection_exception;
 608         pgm_check_table[5] = &addressing_exception;
 609         pgm_check_table[6] = &specification_exception;
 610         pgm_check_table[7] = &data_exception;
 611         pgm_check_table[8] = &overflow_exception;
 612         pgm_check_table[9] = &divide_exception;
 613         pgm_check_table[0x0A] = &overflow_exception;
 614         pgm_check_table[0x0B] = &divide_exception;
 615         pgm_check_table[0x0C] = &hfp_overflow_exception;
 616         pgm_check_table[0x0D] = &hfp_underflow_exception;
 617         pgm_check_table[0x0E] = &hfp_significance_exception;
 618         pgm_check_table[0x0F] = &hfp_divide_exception;
 619         pgm_check_table[0x10] = &do_dat_exception;
 620         pgm_check_table[0x11] = &do_dat_exception;
 621         pgm_check_table[0x12] = &translation_exception;
 622         pgm_check_table[0x13] = &special_op_exception;
 623 #ifndef CONFIG_ARCH_S390X
 624         pgm_check_table[0x14] = &do_pseudo_page_fault;
 625 #else /* CONFIG_ARCH_S390X */
 626         pgm_check_table[0x38] = &do_dat_exception;
 627         pgm_check_table[0x39] = &do_dat_exception;
 628         pgm_check_table[0x3A] = &do_dat_exception;
 629         pgm_check_table[0x3B] = &do_dat_exception;
 630 #endif /* CONFIG_ARCH_S390X */
 631         pgm_check_table[0x15] = &operand_exception;
 632         pgm_check_table[0x1C] = &privileged_op;
 633         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 634         pgm_check_table[0x40] = &do_monitor_call;
 635
 636         if (MACHINE_IS_VM) {
 637                 /*
 638                  * First try to get pfault pseudo page faults going.
 639                  * If this isn't available turn on pagex page faults.
 640                  */
 641 #ifdef CONFIG_PFAULT
 642                 /* request the 0x2603 external interrupt */
 643                 if (register_early_external_interrupt(0x2603, pfault_interrupt,
 644                                                       &ext_int_pfault) != 0)
 645                         panic("Couldn't request external interrupt 0x2603");
 646
 647                 if (pfault_init() == 0)
 648                         return;
 649
 650                 /* Tough luck, no pfault. */
 651                 unregister_early_external_interrupt(0x2603, pfault_interrupt,
 652                                                     &ext_int_pfault);
 653 #endif
 654 #ifndef CONFIG_ARCH_S390X
 655                 cpcmd("SET PAGEX ON", NULL, 0);
 656 #endif
 657         }
 658 }