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