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 FOURLONG "%08lx %08lx %08lx %08lx\n"
  71 static int kstack_depth_to_print = 12;
  72 #else /* CONFIG_ARCH_S390X */
  73 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  74 static int kstack_depth_to_print = 20;
  75 #endif /* CONFIG_ARCH_S390X */
  76
  77 /*
  78  * For show_trace we have tree different stack to consider:
  79  *   - the panic stack which is used if the kernel stack has overflown
  80  *   - the asynchronous interrupt stack (cpu related)
  81  *   - the synchronous kernel stack (process related)
  82  * The stack trace can start at any of the three stack and can potentially
  83  * touch all of them. The order is: panic stack, async stack, sync stack.
  84  */
  85 static unsigned long
  86 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  87 {
  88         struct stack_frame *sf;
  89         struct pt_regs *regs;
  90
  91         while (1) {
  92                 sp = sp & PSW_ADDR_INSN;
  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                 /* Follow the backchain. */
  99                 while (1) {
 100                         low = sp;
 101                         sp = sf->back_chain & PSW_ADDR_INSN;
 102                         if (!sp)
 103                                 break;
 104                         if (sp <= low || sp > high - sizeof(*sf))
 105                                 return sp;
 106                         sf = (struct stack_frame *) sp;
 107                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 108                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 109                 }
 110                 /* Zero backchain detected, check for interrupt frame. */
 111                 sp = (unsigned long) (sf + 1);
 112                 if (sp <= low || sp > high - sizeof(*regs))
 113                         return sp;
 114                 regs = (struct pt_regs *) sp;
 115                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 116                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 117                 low = sp;
 118                 sp = regs->gprs[15];
 119         }
 120 }
 121
 122 void show_trace(struct task_struct *task, unsigned long * stack)
 123 {
 124         register unsigned long __r15 asm ("15");
 125         unsigned long sp;
 126
 127         sp = (unsigned long) stack;
 128         if (!sp)
 129                 sp = task ? task->thread.ksp : __r15;
 130         printk("Call Trace:\n");
 131 #ifdef CONFIG_CHECK_STACK
 132         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 133                           S390_lowcore.panic_stack);
 134 #endif
 135         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 136                           S390_lowcore.async_stack);
 137         if (task)
 138                 __show_trace(sp, (unsigned long) task->thread_info,
 139                              (unsigned long) task->thread_info + THREAD_SIZE);
 140         else
 141                 __show_trace(sp, S390_lowcore.thread_info,
 142                              S390_lowcore.thread_info + THREAD_SIZE);
 143         printk("\n");
 144 }
 145
 146 void show_stack(struct task_struct *task, unsigned long *sp)
 147 {
 148         register unsigned long * __r15 asm ("15");
 149         unsigned long *stack;
 150         int i;
 151
 152         // debugging aid: "show_stack(NULL);" prints the
 153         // back trace for this cpu.
 154
 155         if (!sp)
 156                 sp = task ? (unsigned long *) task->thread.ksp : __r15;
 157
 158         stack = sp;
 159         for (i = 0; i < kstack_depth_to_print; i++) {
 160                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 161                         break;
 162                 if (i && ((i * sizeof (long) % 32) == 0))
 163                         printk("\n       ");
 164                 printk("%p ", (void *)*stack++);
 165         }
 166         printk("\n");
 167         show_trace(task, sp);
 168 }
 169
 170 /*
 171  * The architecture-independent dump_stack generator
 172  */
 173 void dump_stack(void)
 174 {
 175         show_stack(0, 0);
 176 }
 177
 178 EXPORT_SYMBOL(dump_stack);
 179
 180 void show_registers(struct pt_regs *regs)
 181 {
 182         mm_segment_t old_fs;
 183         char *mode;
 184         int i;
 185
 186         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 187         printk("%s PSW : %p %p",
 188                mode, (void *) regs->psw.mask,
 189                (void *) regs->psw.addr);
 190         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 191         printk("%s GPRS: " FOURLONG, mode,
 192                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 193         printk("           " FOURLONG,
 194                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 195         printk("           " FOURLONG,
 196                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 197         printk("           " FOURLONG,
 198                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 199
 200 #if 0
 201         /* FIXME: this isn't needed any more but it changes the ksymoops
 202          * input. To remove or not to remove ... */
 203         save_access_regs(regs->acrs);
 204         printk("%s ACRS: %08x %08x %08x %08x\n", mode,
 205                regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
 206         printk("           %08x %08x %08x %08x\n",
 207                regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
 208         printk("           %08x %08x %08x %08x\n",
 209                regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
 210         printk("           %08x %08x %08x %08x\n",
 211                regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
 212 #endif
 213
 214         /*
 215          * Print the first 20 byte of the instruction stream at the
 216          * time of the fault.
 217          */
 218         old_fs = get_fs();
 219         if (regs->psw.mask & PSW_MASK_PSTATE)
 220                 set_fs(USER_DS);
 221         else
 222                 set_fs(KERNEL_DS);
 223         printk("%s Code: ", mode);
 224         for (i = 0; i < 20; i++) {
 225                 unsigned char c;
 226                 if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
 227                         printk(" Bad PSW.");
 228                         break;
 229                 }
 230                 printk("%02x ", c);
 231         }
 232         set_fs(old_fs);
 233
 234         printk("\n");
 235 }
 236
 237 /* This is called from fs/proc/array.c */
 238 char *task_show_regs(struct task_struct *task, char *buffer)
 239 {
 240         struct pt_regs *regs;
 241
 242         regs = __KSTK_PTREGS(task);
 243         buffer += sprintf(buffer, "task: %p, ksp: %p\n",
 244                        task, (void *)task->thread.ksp);
 245         buffer += sprintf(buffer, "User PSW : %p %p\n",
 246                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 247
 248         buffer += sprintf(buffer, "User GPRS: " FOURLONG,
 249                           regs->gprs[0], regs->gprs[1],
 250                           regs->gprs[2], regs->gprs[3]);
 251         buffer += sprintf(buffer, "           " FOURLONG,
 252                           regs->gprs[4], regs->gprs[5],
 253                           regs->gprs[6], regs->gprs[7]);
 254         buffer += sprintf(buffer, "           " FOURLONG,
 255                           regs->gprs[8], regs->gprs[9],
 256                           regs->gprs[10], regs->gprs[11]);
 257         buffer += sprintf(buffer, "           " FOURLONG,
 258                           regs->gprs[12], regs->gprs[13],
 259                           regs->gprs[14], regs->gprs[15]);
 260         buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
 261                           task->thread.acrs[0], task->thread.acrs[1],
 262                           task->thread.acrs[2], task->thread.acrs[3]);
 263         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 264                           task->thread.acrs[4], task->thread.acrs[5],
 265                           task->thread.acrs[6], task->thread.acrs[7]);
 266         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 267                           task->thread.acrs[8], task->thread.acrs[9],
 268                           task->thread.acrs[10], task->thread.acrs[11]);
 269         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 270                           task->thread.acrs[12], task->thread.acrs[13],
 271                           task->thread.acrs[14], task->thread.acrs[15]);
 272         return buffer;
 273 }
 274
 275 spinlock_t die_lock = SPIN_LOCK_UNLOCKED;
 276
 277 void die(const char * str, struct pt_regs * regs, long err)
 278 {
 279         static int die_counter;
 280         console_verbose();
 281         spin_lock_irq(&die_lock);
 282         bust_spinlocks(1);
 283         printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 284         show_regs(regs);
 285         bust_spinlocks(0);
 286         spin_unlock_irq(&die_lock);
 287         if (in_interrupt())
 288                 panic("Fatal exception in interrupt");
 289         if (panic_on_oops)
 290                 panic("Fatal exception: panic_on_oops");
 291         do_exit(SIGSEGV);
 292 }
 293
 294 static void inline do_trap(long interruption_code, int signr, char *str,
 295                            struct pt_regs *regs, siginfo_t *info)
 296 {
 297         /*
 298          * We got all needed information from the lowcore and can
 299          * now safely switch on interrupts.
 300          */
 301         if (regs->psw.mask & PSW_MASK_PSTATE)
 302                 local_irq_enable();
 303
 304         if (regs->psw.mask & PSW_MASK_PSTATE) {
 305                 struct task_struct *tsk = current;
 306
 307                 tsk->thread.trap_no = interruption_code & 0xffff;
 308                 if (info)
 309                         force_sig_info(signr, info, tsk);
 310                 else
 311                         force_sig(signr, tsk);
 312 #ifndef CONFIG_SYSCTL
 313 #ifdef CONFIG_PROCESS_DEBUG
 314                 printk("User process fault: interruption code 0x%lX\n",
 315                        interruption_code);
 316                 show_regs(regs);
 317 #endif
 318 #else
 319                 if (sysctl_userprocess_debug) {
 320                         printk("User process fault: interruption code 0x%lX\n",
 321                                interruption_code);
 322                         show_regs(regs);
 323                 }
 324 #endif
 325         } else {
 326                 const struct exception_table_entry *fixup;
 327                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 328                 if (fixup)
 329                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 330                 else
 331                         die(str, regs, interruption_code);
 332         }
 333 }
 334
 335 static inline void *get_check_address(struct pt_regs *regs)
 336 {
 337         return (void *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 338 }
 339
 340 void do_single_step(struct pt_regs *regs)
 341 {
 342         if ((current->ptrace & PT_PTRACED) != 0)
 343                 force_sig(SIGTRAP, current);
 344 }
 345
 346 #define DO_ERROR(signr, str, name) \
 347 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
 348 { \
 349         do_trap(interruption_code, signr, str, regs, NULL); \
 350 }
 351
 352 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 353 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
 354 { \
 355         siginfo_t info; \
 356         info.si_signo = signr; \
 357         info.si_errno = 0; \
 358         info.si_code = sicode; \
 359         info.si_addr = (void *)siaddr; \
 360         do_trap(interruption_code, signr, str, regs, &info); \
 361 }
 362
 363 DO_ERROR(SIGSEGV, "Unknown program exception", default_trap_handler)
 364
 365 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 366               ILL_ILLADR, get_check_address(regs))
 367 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 368               ILL_ILLOPN, get_check_address(regs))
 369 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 370               FPE_INTDIV, get_check_address(regs))
 371 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 372               FPE_INTOVF, get_check_address(regs))
 373 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 374               FPE_FLTOVF, get_check_address(regs))
 375 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 376               FPE_FLTUND, get_check_address(regs))
 377 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 378               FPE_FLTRES, get_check_address(regs))
 379 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 380               FPE_FLTDIV, get_check_address(regs))
 381 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 382               FPE_FLTINV, get_check_address(regs))
 383 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 384               ILL_ILLOPN, get_check_address(regs))
 385 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 386               ILL_PRVOPC, get_check_address(regs))
 387 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 388               ILL_ILLOPN, get_check_address(regs))
 389 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 390               ILL_ILLOPN, get_check_address(regs))
 391
 392 static inline void
 393 do_fp_trap(struct pt_regs *regs, void *location,
 394            int fpc, long interruption_code)
 395 {
 396         siginfo_t si;
 397
 398         si.si_signo = SIGFPE;
 399         si.si_errno = 0;
 400         si.si_addr = location;
 401         si.si_code = 0;
 402         /* FPC[2] is Data Exception Code */
 403         if ((fpc & 0x00000300) == 0) {
 404                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 405                 if (fpc & 0x8000) /* invalid fp operation */
 406                         si.si_code = FPE_FLTINV;
 407                 else if (fpc & 0x4000) /* div by 0 */
 408                         si.si_code = FPE_FLTDIV;
 409                 else if (fpc & 0x2000) /* overflow */
 410                         si.si_code = FPE_FLTOVF;
 411                 else if (fpc & 0x1000) /* underflow */
 412                         si.si_code = FPE_FLTUND;
 413                 else if (fpc & 0x0800) /* inexact */
 414                         si.si_code = FPE_FLTRES;
 415         }
 416         current->thread.ieee_instruction_pointer = (addr_t) location;
 417         do_trap(interruption_code, SIGFPE,
 418                 "floating point exception", regs, &si);
 419 }
 420
 421 asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
 422 {
 423         __u8 opcode[6];
 424         __u16 *location;
 425         int signal = 0;
 426
 427         location = (__u16 *) get_check_address(regs);
 428
 429         /*
 430          * We got all needed information from the lowcore and can
 431          * now safely switch on interrupts.
 432          */
 433         if (regs->psw.mask & PSW_MASK_PSTATE)
 434                 local_irq_enable();
 435
 436         if (regs->psw.mask & PSW_MASK_PSTATE) {
 437                 get_user(*((__u16 *) opcode), (__u16 __user *) location);
 438                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 439                         if (current->ptrace & PT_PTRACED)
 440                                 force_sig(SIGTRAP, current);
 441                         else
 442                                 signal = SIGILL;
 443 #ifdef CONFIG_MATHEMU
 444                 } else if (opcode[0] == 0xb3) {
 445                         get_user(*((__u16 *) (opcode+2)), location+1);
 446                         signal = math_emu_b3(opcode, regs);
 447                 } else if (opcode[0] == 0xed) {
 448                         get_user(*((__u32 *) (opcode+2)),
 449                                  (__u32 *)(location+1));
 450                         signal = math_emu_ed(opcode, regs);
 451                 } else if (*((__u16 *) opcode) == 0xb299) {
 452                         get_user(*((__u16 *) (opcode+2)), location+1);
 453                         signal = math_emu_srnm(opcode, regs);
 454                 } else if (*((__u16 *) opcode) == 0xb29c) {
 455                         get_user(*((__u16 *) (opcode+2)), location+1);
 456                         signal = math_emu_stfpc(opcode, regs);
 457                 } else if (*((__u16 *) opcode) == 0xb29d) {
 458                         get_user(*((__u16 *) (opcode+2)), location+1);
 459                         signal = math_emu_lfpc(opcode, regs);
 460 #endif
 461                 } else
 462                         signal = SIGILL;
 463         } else
 464                 signal = SIGILL;
 465
 466         if (signal == SIGFPE)
 467                 do_fp_trap(regs, location,
 468                            current->thread.fp_regs.fpc, interruption_code);
 469         else if (signal)
 470                 do_trap(interruption_code, signal,
 471                         "illegal operation", regs, NULL);
 472 }
 473
 474
 475 #ifdef CONFIG_MATHEMU
 476 asmlinkage void
 477 specification_exception(struct pt_regs * regs, long interruption_code)
 478 {
 479         __u8 opcode[6];
 480         __u16 *location = NULL;
 481         int signal = 0;
 482
 483         location = (__u16 *) get_check_address(regs);
 484
 485         /*
 486          * We got all needed information from the lowcore and can
 487          * now safely switch on interrupts.
 488          */
 489         if (regs->psw.mask & PSW_MASK_PSTATE)
 490                 local_irq_enable();
 491
 492         if (regs->psw.mask & PSW_MASK_PSTATE) {
 493                 get_user(*((__u16 *) opcode), location);
 494                 switch (opcode[0]) {
 495                 case 0x28: /* LDR Rx,Ry   */
 496                         signal = math_emu_ldr(opcode);
 497                         break;
 498                 case 0x38: /* LER Rx,Ry   */
 499                         signal = math_emu_ler(opcode);
 500                         break;
 501                 case 0x60: /* STD R,D(X,B) */
 502                         get_user(*((__u16 *) (opcode+2)), location+1);
 503                         signal = math_emu_std(opcode, regs);
 504                         break;
 505                 case 0x68: /* LD R,D(X,B) */
 506                         get_user(*((__u16 *) (opcode+2)), location+1);
 507                         signal = math_emu_ld(opcode, regs);
 508                         break;
 509                 case 0x70: /* STE R,D(X,B) */
 510                         get_user(*((__u16 *) (opcode+2)), location+1);
 511                         signal = math_emu_ste(opcode, regs);
 512                         break;
 513                 case 0x78: /* LE R,D(X,B) */
 514                         get_user(*((__u16 *) (opcode+2)), location+1);
 515                         signal = math_emu_le(opcode, regs);
 516                         break;
 517                 default:
 518                         signal = SIGILL;
 519                         break;
 520                 }
 521         } else
 522                 signal = SIGILL;
 523
 524         if (signal == SIGFPE)
 525                 do_fp_trap(regs, location,
 526                            current->thread.fp_regs.fpc, interruption_code);
 527         else if (signal) {
 528                 siginfo_t info;
 529                 info.si_signo = signal;
 530                 info.si_errno = 0;
 531                 info.si_code = ILL_ILLOPN;
 532                 info.si_addr = location;
 533                 do_trap(interruption_code, signal,
 534                         "specification exception", regs, &info);
 535         }
 536 }
 537 #else
 538 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 539               ILL_ILLOPN, get_check_address(regs));
 540 #endif
 541
 542 asmlinkage void data_exception(struct pt_regs * regs, long interruption_code)
 543 {
 544         __u16 *location;
 545         int signal = 0;
 546
 547         location = (__u16 *) get_check_address(regs);
 548
 549         /*
 550          * We got all needed information from the lowcore and can
 551          * now safely switch on interrupts.
 552          */
 553         if (regs->psw.mask & PSW_MASK_PSTATE)
 554                 local_irq_enable();
 555
 556         if (MACHINE_HAS_IEEE)
 557                 __asm__ volatile ("stfpc %0\n\t"
 558                                   : "=m" (current->thread.fp_regs.fpc));
 559
 560 #ifdef CONFIG_MATHEMU
 561         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 562                 __u8 opcode[6];
 563                 get_user(*((__u16 *) opcode), location);
 564                 switch (opcode[0]) {
 565                 case 0x28: /* LDR Rx,Ry   */
 566                         signal = math_emu_ldr(opcode);
 567                         break;
 568                 case 0x38: /* LER Rx,Ry   */
 569                         signal = math_emu_ler(opcode);
 570                         break;
 571                 case 0x60: /* STD R,D(X,B) */
 572                         get_user(*((__u16 *) (opcode+2)), location+1);
 573                         signal = math_emu_std(opcode, regs);
 574                         break;
 575                 case 0x68: /* LD R,D(X,B) */
 576                         get_user(*((__u16 *) (opcode+2)), location+1);
 577                         signal = math_emu_ld(opcode, regs);
 578                         break;
 579                 case 0x70: /* STE R,D(X,B) */
 580                         get_user(*((__u16 *) (opcode+2)), location+1);
 581                         signal = math_emu_ste(opcode, regs);
 582                         break;
 583                 case 0x78: /* LE R,D(X,B) */
 584                         get_user(*((__u16 *) (opcode+2)), location+1);
 585                         signal = math_emu_le(opcode, regs);
 586                         break;
 587                 case 0xb3:
 588                         get_user(*((__u16 *) (opcode+2)), location+1);
 589                         signal = math_emu_b3(opcode, regs);
 590                         break;
 591                 case 0xed:
 592                         get_user(*((__u32 *) (opcode+2)),
 593                                  (__u32 *)(location+1));
 594                         signal = math_emu_ed(opcode, regs);
 595                         break;
 596                 case 0xb2:
 597                         if (opcode[1] == 0x99) {
 598                                 get_user(*((__u16 *) (opcode+2)), location+1);
 599                                 signal = math_emu_srnm(opcode, regs);
 600                         } else if (opcode[1] == 0x9c) {
 601                                 get_user(*((__u16 *) (opcode+2)), location+1);
 602                                 signal = math_emu_stfpc(opcode, regs);
 603                         } else if (opcode[1] == 0x9d) {
 604                                 get_user(*((__u16 *) (opcode+2)), location+1);
 605                                 signal = math_emu_lfpc(opcode, regs);
 606                         } else
 607                                 signal = SIGILL;
 608                         break;
 609                 default:
 610                         signal = SIGILL;
 611                         break;
 612                 }
 613         }
 614 #endif
 615         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 616                 signal = SIGFPE;
 617         else
 618                 signal = SIGILL;
 619         if (signal == SIGFPE)
 620                 do_fp_trap(regs, location,
 621                            current->thread.fp_regs.fpc, interruption_code);
 622         else if (signal) {
 623                 siginfo_t info;
 624                 info.si_signo = signal;
 625                 info.si_errno = 0;
 626                 info.si_code = ILL_ILLOPN;
 627                 info.si_addr = location;
 628                 do_trap(interruption_code, signal,
 629                         "data exception", regs, &info);
 630         }
 631 }
 632
 633 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 634 {
 635         die("Kernel stack overflow", regs, 0);
 636         panic("Corrupt kernel stack, can't continue.");
 637 }
 638
 639
 640 /* init is done in lowcore.S and head.S */
 641
 642 void __init trap_init(void)
 643 {
 644         int i;
 645
 646         for (i = 0; i < 128; i++)
 647           pgm_check_table[i] = &default_trap_handler;
 648         pgm_check_table[1] = &illegal_op;
 649         pgm_check_table[2] = &privileged_op;
 650         pgm_check_table[3] = &execute_exception;
 651         pgm_check_table[4] = &do_protection_exception;
 652         pgm_check_table[5] = &addressing_exception;
 653         pgm_check_table[6] = &specification_exception;
 654         pgm_check_table[7] = &data_exception;
 655         pgm_check_table[8] = &overflow_exception;
 656         pgm_check_table[9] = &divide_exception;
 657         pgm_check_table[0x0A] = &overflow_exception;
 658         pgm_check_table[0x0B] = &divide_exception;
 659         pgm_check_table[0x0C] = &hfp_overflow_exception;
 660         pgm_check_table[0x0D] = &hfp_underflow_exception;
 661         pgm_check_table[0x0E] = &hfp_significance_exception;
 662         pgm_check_table[0x0F] = &hfp_divide_exception;
 663         pgm_check_table[0x10] = &do_dat_exception;
 664         pgm_check_table[0x11] = &do_dat_exception;
 665         pgm_check_table[0x12] = &translation_exception;
 666         pgm_check_table[0x13] = &special_op_exception;
 667 #ifndef CONFIG_ARCH_S390X
 668         pgm_check_table[0x14] = &do_pseudo_page_fault;
 669 #else /* CONFIG_ARCH_S390X */
 670         pgm_check_table[0x38] = &do_dat_exception;
 671         pgm_check_table[0x39] = &do_dat_exception;
 672         pgm_check_table[0x3A] = &do_dat_exception;
 673         pgm_check_table[0x3B] = &do_dat_exception;
 674 #endif /* CONFIG_ARCH_S390X */
 675         pgm_check_table[0x15] = &operand_exception;
 676         pgm_check_table[0x1C] = &privileged_op;
 677         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 678         pgm_check_table[0x40] = &do_monitor_call;
 679
 680         if (MACHINE_IS_VM) {
 681                 /*
 682                  * First try to get pfault pseudo page faults going.
 683                  * If this isn't available turn on pagex page faults.
 684                  */
 685 #ifdef CONFIG_PFAULT
 686                 /* request the 0x2603 external interrupt */
 687                 if (register_early_external_interrupt(0x2603, pfault_interrupt,
 688                                                       &ext_int_pfault) != 0)
 689                         panic("Couldn't request external interrupt 0x2603");
 690
 691                 if (pfault_init() == 0)
 692                         return;
 693
 694                 /* Tough luck, no pfault. */
 695                 unregister_early_external_interrupt(0x2603, pfault_interrupt,
 696                                                     &ext_int_pfault);
 697 #endif
 698 #ifndef CONFIG_ARCH_S390X
 699                 cpcmd("SET PAGEX ON", NULL, 0);
 700 #endif
 701         }
 702 }