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/sched.h>
  18 #include <linux/kernel.h>
  19 #include <linux/string.h>
  20 #include <linux/errno.h>
  21 #include <linux/tracehook.h>
  22 #include <linux/timer.h>
  23 #include <linux/mm.h>
  24 #include <linux/smp.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/delay.h>
  29 #include <linux/module.h>
  30 #include <linux/kdebug.h>
  31 #include <linux/kallsyms.h>
  32 #include <linux/reboot.h>
  33 #include <linux/kprobes.h>
  34 #include <linux/bug.h>
  35 #include <linux/utsname.h>
  36 #include <asm/system.h>
  37 #include <asm/uaccess.h>
  38 #include <asm/io.h>
  39 #include <asm/atomic.h>
  40 #include <asm/mathemu.h>
  41 #include <asm/cpcmd.h>
  42 #include <asm/s390_ext.h>
  43 #include <asm/lowcore.h>
  44 #include <asm/debug.h>
  45 #include "entry.h"
  46
  47 pgm_check_handler_t *pgm_check_table[128];
  48
  49 int show_unhandled_signals;
  50
  51 extern pgm_check_handler_t do_protection_exception;
  52 extern pgm_check_handler_t do_dat_exception;
  53 extern pgm_check_handler_t do_asce_exception;
  54
  55 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
  56
  57 #ifndef CONFIG_64BIT
  58 #define LONG "%08lx "
  59 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
  60 static int kstack_depth_to_print = 12;
  61 #else /* CONFIG_64BIT */
  62 #define LONG "%016lx "
  63 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  64 static int kstack_depth_to_print = 20;
  65 #endif /* CONFIG_64BIT */
  66
  67 /*
  68  * For show_trace we have tree different stack to consider:
  69  *   - the panic stack which is used if the kernel stack has overflown
  70  *   - the asynchronous interrupt stack (cpu related)
  71  *   - the synchronous kernel stack (process related)
  72  * The stack trace can start at any of the three stack and can potentially
  73  * touch all of them. The order is: panic stack, async stack, sync stack.
  74  */
  75 static unsigned long
  76 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  77 {
  78         struct stack_frame *sf;
  79         struct pt_regs *regs;
  80
  81         while (1) {
  82                 sp = sp & PSW_ADDR_INSN;
  83                 if (sp < low || sp > high - sizeof(*sf))
  84                         return sp;
  85                 sf = (struct stack_frame *) sp;
  86                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  87                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
  88                 /* Follow the backchain. */
  89                 while (1) {
  90                         low = sp;
  91                         sp = sf->back_chain & PSW_ADDR_INSN;
  92                         if (!sp)
  93                                 break;
  94                         if (sp <= low || sp > high - sizeof(*sf))
  95                                 return sp;
  96                         sf = (struct stack_frame *) sp;
  97                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  98                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
  99                 }
 100                 /* Zero backchain detected, check for interrupt frame. */
 101                 sp = (unsigned long) (sf + 1);
 102                 if (sp <= low || sp > high - sizeof(*regs))
 103                         return sp;
 104                 regs = (struct pt_regs *) sp;
 105                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 106                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 107                 low = sp;
 108                 sp = regs->gprs[15];
 109         }
 110 }
 111
 112 static void show_trace(struct task_struct *task, unsigned long *stack)
 113 {
 114         register unsigned long __r15 asm ("15");
 115         unsigned long sp;
 116
 117         sp = (unsigned long) stack;
 118         if (!sp)
 119                 sp = task ? task->thread.ksp : __r15;
 120         printk("Call Trace:\n");
 121 #ifdef CONFIG_CHECK_STACK
 122         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 123                           S390_lowcore.panic_stack);
 124 #endif
 125         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 126                           S390_lowcore.async_stack);
 127         if (task)
 128                 __show_trace(sp, (unsigned long) task_stack_page(task),
 129                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
 130         else
 131                 __show_trace(sp, S390_lowcore.thread_info,
 132                              S390_lowcore.thread_info + THREAD_SIZE);
 133         if (!task)
 134                 task = current;
 135         debug_show_held_locks(task);
 136 }
 137
 138 void show_stack(struct task_struct *task, unsigned long *sp)
 139 {
 140         register unsigned long * __r15 asm ("15");
 141         unsigned long *stack;
 142         int i;
 143
 144         if (!sp)
 145                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
 146         else
 147                 stack = sp;
 148
 149         for (i = 0; i < kstack_depth_to_print; i++) {
 150                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 151                         break;
 152                 if (i && ((i * sizeof (long) % 32) == 0))
 153                         printk("\n       ");
 154                 printk(LONG, *stack++);
 155         }
 156         printk("\n");
 157         show_trace(task, sp);
 158 }
 159
 160 static void show_last_breaking_event(struct pt_regs *regs)
 161 {
 162 #ifdef CONFIG_64BIT
 163         printk("Last Breaking-Event-Address:\n");
 164         printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
 165         print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
 166 #endif
 167 }
 168
 169 /*
 170  * The architecture-independent dump_stack generator
 171  */
 172 void dump_stack(void)
 173 {
 174         printk("CPU: %d %s %s %.*s\n",
 175                task_thread_info(current)->cpu, print_tainted(),
 176                init_utsname()->release,
 177                (int)strcspn(init_utsname()->version, " "),
 178                init_utsname()->version);
 179         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 180                current->comm, current->pid, current,
 181                (void *) current->thread.ksp);
 182         show_stack(NULL, NULL);
 183 }
 184 EXPORT_SYMBOL(dump_stack);
 185
 186 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 187 {
 188         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 189 }
 190
 191 void show_registers(struct pt_regs *regs)
 192 {
 193         char *mode;
 194
 195         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 196         printk("%s PSW : %p %p",
 197                mode, (void *) regs->psw.mask,
 198                (void *) regs->psw.addr);
 199         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 200         printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 201                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 202                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 203                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 204                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 205                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 206                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 207 #ifdef CONFIG_64BIT
 208         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 209 #endif
 210         printk("\n%s GPRS: " FOURLONG, mode,
 211                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 212         printk("           " FOURLONG,
 213                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 214         printk("           " FOURLONG,
 215                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 216         printk("           " FOURLONG,
 217                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 218
 219         show_code(regs);
 220 }
 221
 222 void show_regs(struct pt_regs *regs)
 223 {
 224         print_modules();
 225         printk("CPU: %d %s %s %.*s\n",
 226                task_thread_info(current)->cpu, print_tainted(),
 227                init_utsname()->release,
 228                (int)strcspn(init_utsname()->version, " "),
 229                init_utsname()->version);
 230         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 231                current->comm, current->pid, current,
 232                (void *) current->thread.ksp);
 233         show_registers(regs);
 234         /* Show stack backtrace if pt_regs is from kernel mode */
 235         if (!(regs->psw.mask & PSW_MASK_PSTATE))
 236                 show_trace(NULL, (unsigned long *) regs->gprs[15]);
 237         show_last_breaking_event(regs);
 238 }
 239
 240 static DEFINE_SPINLOCK(die_lock);
 241
 242 void die(const char * str, struct pt_regs * regs, long err)
 243 {
 244         static int die_counter;
 245
 246         oops_enter();
 247         debug_stop_all();
 248         console_verbose();
 249         spin_lock_irq(&die_lock);
 250         bust_spinlocks(1);
 251         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 252 #ifdef CONFIG_PREEMPT
 253         printk("PREEMPT ");
 254 #endif
 255 #ifdef CONFIG_SMP
 256         printk("SMP ");
 257 #endif
 258 #ifdef CONFIG_DEBUG_PAGEALLOC
 259         printk("DEBUG_PAGEALLOC");
 260 #endif
 261         printk("\n");
 262         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
 263         show_regs(regs);
 264         bust_spinlocks(0);
 265         add_taint(TAINT_DIE);
 266         spin_unlock_irq(&die_lock);
 267         if (in_interrupt())
 268                 panic("Fatal exception in interrupt");
 269         if (panic_on_oops)
 270                 panic("Fatal exception: panic_on_oops");
 271         oops_exit();
 272         do_exit(SIGSEGV);
 273 }
 274
 275 static void inline report_user_fault(struct pt_regs *regs, long int_code,
 276                                      int signr)
 277 {
 278         if ((task_pid_nr(current) > 1) && !show_unhandled_signals)
 279                 return;
 280         if (!unhandled_signal(current, signr))
 281                 return;
 282         if (!printk_ratelimit())
 283                 return;
 284         printk("User process fault: interruption code 0x%lX ", int_code);
 285         print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN);
 286         printk("\n");
 287         show_regs(regs);
 288 }
 289
 290 int is_valid_bugaddr(unsigned long addr)
 291 {
 292         return 1;
 293 }
 294
 295 static inline void __kprobes do_trap(long pgm_int_code, int signr, char *str,
 296                                      struct pt_regs *regs, siginfo_t *info)
 297 {
 298         if (notify_die(DIE_TRAP, str, regs, pgm_int_code,
 299                        pgm_int_code, signr) == NOTIFY_STOP)
 300                 return;
 301
 302         if (regs->psw.mask & PSW_MASK_PSTATE) {
 303                 struct task_struct *tsk = current;
 304
 305                 tsk->thread.trap_no = pgm_int_code & 0xffff;
 306                 force_sig_info(signr, info, tsk);
 307                 report_user_fault(regs, pgm_int_code, signr);
 308         } else {
 309                 const struct exception_table_entry *fixup;
 310                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 311                 if (fixup)
 312                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 313                 else {
 314                         enum bug_trap_type btt;
 315
 316                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 317                         if (btt == BUG_TRAP_TYPE_WARN)
 318                                 return;
 319                         die(str, regs, pgm_int_code);
 320                 }
 321         }
 322 }
 323
 324 static inline void __user *get_psw_address(struct pt_regs *regs,
 325                                            long pgm_int_code)
 326 {
 327         return (void __user *)
 328                 ((regs->psw.addr - (pgm_int_code >> 16)) & PSW_ADDR_INSN);
 329 }
 330
 331 void __kprobes do_per_trap(struct pt_regs *regs)
 332 {
 333         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
 334                 return;
 335         if (tracehook_consider_fatal_signal(current, SIGTRAP))
 336                 force_sig(SIGTRAP, current);
 337 }
 338
 339 static void default_trap_handler(struct pt_regs *regs, long pgm_int_code,
 340                                  unsigned long trans_exc_code)
 341 {
 342         if (regs->psw.mask & PSW_MASK_PSTATE) {
 343                 report_user_fault(regs, pgm_int_code, SIGSEGV);
 344                 do_exit(SIGSEGV);
 345         } else
 346                 die("Unknown program exception", regs, pgm_int_code);
 347 }
 348
 349 #define DO_ERROR_INFO(name, signr, sicode, str) \
 350 static void name(struct pt_regs *regs, long pgm_int_code, \
 351                  unsigned long trans_exc_code) \
 352 { \
 353         siginfo_t info; \
 354         info.si_signo = signr; \
 355         info.si_errno = 0; \
 356         info.si_code = sicode; \
 357         info.si_addr = get_psw_address(regs, pgm_int_code); \
 358         do_trap(pgm_int_code, signr, str, regs, &info);     \
 359 }
 360
 361 DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
 362               "addressing exception")
 363 DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
 364               "execute exception")
 365 DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
 366               "fixpoint divide exception")
 367 DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
 368               "fixpoint overflow exception")
 369 DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
 370               "HFP overflow exception")
 371 DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
 372               "HFP underflow exception")
 373 DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
 374               "HFP significance exception")
 375 DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
 376               "HFP divide exception")
 377 DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
 378               "HFP square root exception")
 379 DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
 380               "operand exception")
 381 DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
 382               "privileged operation")
 383 DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
 384               "special operation exception")
 385 DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN,
 386               "translation exception")
 387
 388 static inline void do_fp_trap(struct pt_regs *regs, void __user *location,
 389                               int fpc, long pgm_int_code)
 390 {
 391         siginfo_t si;
 392
 393         si.si_signo = SIGFPE;
 394         si.si_errno = 0;
 395         si.si_addr = location;
 396         si.si_code = 0;
 397         /* FPC[2] is Data Exception Code */
 398         if ((fpc & 0x00000300) == 0) {
 399                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 400                 if (fpc & 0x8000) /* invalid fp operation */
 401                         si.si_code = FPE_FLTINV;
 402                 else if (fpc & 0x4000) /* div by 0 */
 403                         si.si_code = FPE_FLTDIV;
 404                 else if (fpc & 0x2000) /* overflow */
 405                         si.si_code = FPE_FLTOVF;
 406                 else if (fpc & 0x1000) /* underflow */
 407                         si.si_code = FPE_FLTUND;
 408                 else if (fpc & 0x0800) /* inexact */
 409                         si.si_code = FPE_FLTRES;
 410         }
 411         do_trap(pgm_int_code, SIGFPE,
 412                 "floating point exception", regs, &si);
 413 }
 414
 415 static void __kprobes illegal_op(struct pt_regs *regs, long pgm_int_code,
 416                                  unsigned long trans_exc_code)
 417 {
 418         siginfo_t info;
 419         __u8 opcode[6];
 420         __u16 __user *location;
 421         int signal = 0;
 422
 423         location = get_psw_address(regs, pgm_int_code);
 424
 425         if (regs->psw.mask & PSW_MASK_PSTATE) {
 426                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 427                         return;
 428                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 429                         if (tracehook_consider_fatal_signal(current, SIGTRAP))
 430                                 force_sig(SIGTRAP, current);
 431                         else
 432                                 signal = SIGILL;
 433 #ifdef CONFIG_MATHEMU
 434                 } else if (opcode[0] == 0xb3) {
 435                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 436                                 return;
 437                         signal = math_emu_b3(opcode, regs);
 438                 } else if (opcode[0] == 0xed) {
 439                         if (get_user(*((__u32 *) (opcode+2)),
 440                                      (__u32 __user *)(location+1)))
 441                                 return;
 442                         signal = math_emu_ed(opcode, regs);
 443                 } else if (*((__u16 *) opcode) == 0xb299) {
 444                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 445                                 return;
 446                         signal = math_emu_srnm(opcode, regs);
 447                 } else if (*((__u16 *) opcode) == 0xb29c) {
 448                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 449                                 return;
 450                         signal = math_emu_stfpc(opcode, regs);
 451                 } else if (*((__u16 *) opcode) == 0xb29d) {
 452                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 453                                 return;
 454                         signal = math_emu_lfpc(opcode, regs);
 455 #endif
 456                 } else
 457                         signal = SIGILL;
 458         } else {
 459                 /*
 460                  * If we get an illegal op in kernel mode, send it through the
 461                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 462                  */
 463                 if (notify_die(DIE_BPT, "bpt", regs, pgm_int_code,
 464                                3, SIGTRAP) != NOTIFY_STOP)
 465                         signal = SIGILL;
 466         }
 467
 468 #ifdef CONFIG_MATHEMU
 469         if (signal == SIGFPE)
 470                 do_fp_trap(regs, location,
 471                            current->thread.fp_regs.fpc, pgm_int_code);
 472         else if (signal == SIGSEGV) {
 473                 info.si_signo = signal;
 474                 info.si_errno = 0;
 475                 info.si_code = SEGV_MAPERR;
 476                 info.si_addr = (void __user *) location;
 477                 do_trap(pgm_int_code, signal,
 478                         "user address fault", regs, &info);
 479         } else
 480 #endif
 481         if (signal) {
 482                 info.si_signo = signal;
 483                 info.si_errno = 0;
 484                 info.si_code = ILL_ILLOPC;
 485                 info.si_addr = (void __user *) location;
 486                 do_trap(pgm_int_code, signal,
 487                         "illegal operation", regs, &info);
 488         }
 489 }
 490
 491
 492 #ifdef CONFIG_MATHEMU
 493 asmlinkage void specification_exception(struct pt_regs *regs,
 494                                         long pgm_int_code,
 495                                         unsigned long trans_exc_code)
 496 {
 497         __u8 opcode[6];
 498         __u16 __user *location = NULL;
 499         int signal = 0;
 500
 501         location = (__u16 __user *) get_psw_address(regs, pgm_int_code);
 502
 503         if (regs->psw.mask & PSW_MASK_PSTATE) {
 504                 get_user(*((__u16 *) opcode), location);
 505                 switch (opcode[0]) {
 506                 case 0x28: /* LDR Rx,Ry   */
 507                         signal = math_emu_ldr(opcode);
 508                         break;
 509                 case 0x38: /* LER Rx,Ry   */
 510                         signal = math_emu_ler(opcode);
 511                         break;
 512                 case 0x60: /* STD R,D(X,B) */
 513                         get_user(*((__u16 *) (opcode+2)), location+1);
 514                         signal = math_emu_std(opcode, regs);
 515                         break;
 516                 case 0x68: /* LD R,D(X,B) */
 517                         get_user(*((__u16 *) (opcode+2)), location+1);
 518                         signal = math_emu_ld(opcode, regs);
 519                         break;
 520                 case 0x70: /* STE R,D(X,B) */
 521                         get_user(*((__u16 *) (opcode+2)), location+1);
 522                         signal = math_emu_ste(opcode, regs);
 523                         break;
 524                 case 0x78: /* LE R,D(X,B) */
 525                         get_user(*((__u16 *) (opcode+2)), location+1);
 526                         signal = math_emu_le(opcode, regs);
 527                         break;
 528                 default:
 529                         signal = SIGILL;
 530                         break;
 531                 }
 532         } else
 533                 signal = SIGILL;
 534
 535         if (signal == SIGFPE)
 536                 do_fp_trap(regs, location,
 537                            current->thread.fp_regs.fpc, pgm_int_code);
 538         else if (signal) {
 539                 siginfo_t info;
 540                 info.si_signo = signal;
 541                 info.si_errno = 0;
 542                 info.si_code = ILL_ILLOPN;
 543                 info.si_addr = location;
 544                 do_trap(pgm_int_code, signal,
 545                         "specification exception", regs, &info);
 546         }
 547 }
 548 #else
 549 DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
 550               "specification exception");
 551 #endif
 552
 553 static void data_exception(struct pt_regs *regs, long pgm_int_code,
 554                            unsigned long trans_exc_code)
 555 {
 556         __u16 __user *location;
 557         int signal = 0;
 558
 559         location = get_psw_address(regs, pgm_int_code);
 560
 561         if (MACHINE_HAS_IEEE)
 562                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 563
 564 #ifdef CONFIG_MATHEMU
 565         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 566                 __u8 opcode[6];
 567                 get_user(*((__u16 *) opcode), location);
 568                 switch (opcode[0]) {
 569                 case 0x28: /* LDR Rx,Ry   */
 570                         signal = math_emu_ldr(opcode);
 571                         break;
 572                 case 0x38: /* LER Rx,Ry   */
 573                         signal = math_emu_ler(opcode);
 574                         break;
 575                 case 0x60: /* STD R,D(X,B) */
 576                         get_user(*((__u16 *) (opcode+2)), location+1);
 577                         signal = math_emu_std(opcode, regs);
 578                         break;
 579                 case 0x68: /* LD R,D(X,B) */
 580                         get_user(*((__u16 *) (opcode+2)), location+1);
 581                         signal = math_emu_ld(opcode, regs);
 582                         break;
 583                 case 0x70: /* STE R,D(X,B) */
 584                         get_user(*((__u16 *) (opcode+2)), location+1);
 585                         signal = math_emu_ste(opcode, regs);
 586                         break;
 587                 case 0x78: /* LE R,D(X,B) */
 588                         get_user(*((__u16 *) (opcode+2)), location+1);
 589                         signal = math_emu_le(opcode, regs);
 590                         break;
 591                 case 0xb3:
 592                         get_user(*((__u16 *) (opcode+2)), location+1);
 593                         signal = math_emu_b3(opcode, regs);
 594                         break;
 595                 case 0xed:
 596                         get_user(*((__u32 *) (opcode+2)),
 597                                  (__u32 __user *)(location+1));
 598                         signal = math_emu_ed(opcode, regs);
 599                         break;
 600                 case 0xb2:
 601                         if (opcode[1] == 0x99) {
 602                                 get_user(*((__u16 *) (opcode+2)), location+1);
 603                                 signal = math_emu_srnm(opcode, regs);
 604                         } else if (opcode[1] == 0x9c) {
 605                                 get_user(*((__u16 *) (opcode+2)), location+1);
 606                                 signal = math_emu_stfpc(opcode, regs);
 607                         } else if (opcode[1] == 0x9d) {
 608                                 get_user(*((__u16 *) (opcode+2)), location+1);
 609                                 signal = math_emu_lfpc(opcode, regs);
 610                         } else
 611                                 signal = SIGILL;
 612                         break;
 613                 default:
 614                         signal = SIGILL;
 615                         break;
 616                 }
 617         }
 618 #endif
 619         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 620                 signal = SIGFPE;
 621         else
 622                 signal = SIGILL;
 623         if (signal == SIGFPE)
 624                 do_fp_trap(regs, location,
 625                            current->thread.fp_regs.fpc, pgm_int_code);
 626         else if (signal) {
 627                 siginfo_t info;
 628                 info.si_signo = signal;
 629                 info.si_errno = 0;
 630                 info.si_code = ILL_ILLOPN;
 631                 info.si_addr = location;
 632                 do_trap(pgm_int_code, signal, "data exception", regs, &info);
 633         }
 634 }
 635
 636 static void space_switch_exception(struct pt_regs *regs, long pgm_int_code,
 637                                    unsigned long trans_exc_code)
 638 {
 639         siginfo_t info;
 640
 641         /* Set user psw back to home space mode. */
 642         if (regs->psw.mask & PSW_MASK_PSTATE)
 643                 regs->psw.mask |= PSW_ASC_HOME;
 644         /* Send SIGILL. */
 645         info.si_signo = SIGILL;
 646         info.si_errno = 0;
 647         info.si_code = ILL_PRVOPC;
 648         info.si_addr = get_psw_address(regs, pgm_int_code);
 649         do_trap(pgm_int_code, SIGILL, "space switch event", regs, &info);
 650 }
 651
 652 asmlinkage void __kprobes kernel_stack_overflow(struct pt_regs * regs)
 653 {
 654         bust_spinlocks(1);
 655         printk("Kernel stack overflow.\n");
 656         show_regs(regs);
 657         bust_spinlocks(0);
 658         panic("Corrupt kernel stack, can't continue.");
 659 }
 660
 661 /* init is done in lowcore.S and head.S */
 662
 663 void __init trap_init(void)
 664 {
 665         int i;
 666
 667         for (i = 0; i < 128; i++)
 668           pgm_check_table[i] = &default_trap_handler;
 669         pgm_check_table[1] = &illegal_op;
 670         pgm_check_table[2] = &privileged_op;
 671         pgm_check_table[3] = &execute_exception;
 672         pgm_check_table[4] = &do_protection_exception;
 673         pgm_check_table[5] = &addressing_exception;
 674         pgm_check_table[6] = &specification_exception;
 675         pgm_check_table[7] = &data_exception;
 676         pgm_check_table[8] = &overflow_exception;
 677         pgm_check_table[9] = &divide_exception;
 678         pgm_check_table[0x0A] = &overflow_exception;
 679         pgm_check_table[0x0B] = &divide_exception;
 680         pgm_check_table[0x0C] = &hfp_overflow_exception;
 681         pgm_check_table[0x0D] = &hfp_underflow_exception;
 682         pgm_check_table[0x0E] = &hfp_significance_exception;
 683         pgm_check_table[0x0F] = &hfp_divide_exception;
 684         pgm_check_table[0x10] = &do_dat_exception;
 685         pgm_check_table[0x11] = &do_dat_exception;
 686         pgm_check_table[0x12] = &translation_exception;
 687         pgm_check_table[0x13] = &special_op_exception;
 688 #ifdef CONFIG_64BIT
 689         pgm_check_table[0x38] = &do_asce_exception;
 690         pgm_check_table[0x39] = &do_dat_exception;
 691         pgm_check_table[0x3A] = &do_dat_exception;
 692         pgm_check_table[0x3B] = &do_dat_exception;
 693 #endif /* CONFIG_64BIT */
 694         pgm_check_table[0x15] = &operand_exception;
 695         pgm_check_table[0x1C] = &space_switch_exception;
 696         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 697         /* Enable machine checks early. */
 698         local_mcck_enable();
 699 }