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/ptrace.h>
  22 #include <linux/timer.h>
  23 #include <linux/mm.h>
  24 #include <linux/smp.h>
  25 #include <linux/smp_lock.h>
  26 #include <linux/init.h>
  27 #include <linux/interrupt.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 <asm/system.h>
  36 #include <asm/uaccess.h>
  37 #include <asm/io.h>
  38 #include <asm/atomic.h>
  39 #include <asm/mathemu.h>
  40 #include <asm/cpcmd.h>
  41 #include <asm/s390_ext.h>
  42 #include <asm/lowcore.h>
  43 #include <asm/debug.h>
  44
  45 /* Called from entry.S only */
  46 extern void handle_per_exception(struct pt_regs *regs);
  47
  48 typedef void pgm_check_handler_t(struct pt_regs *, long);
  49 pgm_check_handler_t *pgm_check_table[128];
  50
  51 #ifdef CONFIG_SYSCTL
  52 #ifdef CONFIG_PROCESS_DEBUG
  53 int sysctl_userprocess_debug = 1;
  54 #else
  55 int sysctl_userprocess_debug = 0;
  56 #endif
  57 #endif
  58
  59 extern pgm_check_handler_t do_protection_exception;
  60 extern pgm_check_handler_t do_dat_exception;
  61 extern pgm_check_handler_t do_monitor_call;
  62
  63 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
  64
  65 #ifndef CONFIG_64BIT
  66 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
  67 static int kstack_depth_to_print = 12;
  68 #else /* CONFIG_64BIT */
  69 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  70 static int kstack_depth_to_print = 20;
  71 #endif /* CONFIG_64BIT */
  72
  73 /*
  74  * For show_trace we have tree different stack to consider:
  75  *   - the panic stack which is used if the kernel stack has overflown
  76  *   - the asynchronous interrupt stack (cpu related)
  77  *   - the synchronous kernel stack (process related)
  78  * The stack trace can start at any of the three stack and can potentially
  79  * touch all of them. The order is: panic stack, async stack, sync stack.
  80  */
  81 static unsigned long
  82 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  83 {
  84         struct stack_frame *sf;
  85         struct pt_regs *regs;
  86
  87         while (1) {
  88                 sp = sp & PSW_ADDR_INSN;
  89                 if (sp < low || sp > high - sizeof(*sf))
  90                         return sp;
  91                 sf = (struct stack_frame *) sp;
  92                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  93                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
  94                 /* Follow the backchain. */
  95                 while (1) {
  96                         low = sp;
  97                         sp = sf->back_chain & PSW_ADDR_INSN;
  98                         if (!sp)
  99                                 break;
 100                         if (sp <= low || sp > high - sizeof(*sf))
 101                                 return sp;
 102                         sf = (struct stack_frame *) sp;
 103                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 104                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 105                 }
 106                 /* Zero backchain detected, check for interrupt frame. */
 107                 sp = (unsigned long) (sf + 1);
 108                 if (sp <= low || sp > high - sizeof(*regs))
 109                         return sp;
 110                 regs = (struct pt_regs *) sp;
 111                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 112                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 113                 low = sp;
 114                 sp = regs->gprs[15];
 115         }
 116 }
 117
 118 void show_trace(struct task_struct *task, unsigned long *stack)
 119 {
 120         register unsigned long __r15 asm ("15");
 121         unsigned long sp;
 122
 123         sp = (unsigned long) stack;
 124         if (!sp)
 125                 sp = task ? task->thread.ksp : __r15;
 126         printk("Call Trace:\n");
 127 #ifdef CONFIG_CHECK_STACK
 128         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 129                           S390_lowcore.panic_stack);
 130 #endif
 131         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 132                           S390_lowcore.async_stack);
 133         if (task)
 134                 __show_trace(sp, (unsigned long) task_stack_page(task),
 135                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
 136         else
 137                 __show_trace(sp, S390_lowcore.thread_info,
 138                              S390_lowcore.thread_info + THREAD_SIZE);
 139         printk("\n");
 140         if (!task)
 141                 task = current;
 142         debug_show_held_locks(task);
 143 }
 144
 145 void show_stack(struct task_struct *task, unsigned long *sp)
 146 {
 147         register unsigned long * __r15 asm ("15");
 148         unsigned long *stack;
 149         int i;
 150
 151         if (!sp)
 152                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
 153         else
 154                 stack = sp;
 155
 156         for (i = 0; i < kstack_depth_to_print; i++) {
 157                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 158                         break;
 159                 if (i && ((i * sizeof (long) % 32) == 0))
 160                         printk("\n       ");
 161                 printk("%p ", (void *)*stack++);
 162         }
 163         printk("\n");
 164         show_trace(task, sp);
 165 }
 166
 167 /*
 168  * The architecture-independent dump_stack generator
 169  */
 170 void dump_stack(void)
 171 {
 172         show_stack(NULL, NULL);
 173 }
 174
 175 EXPORT_SYMBOL(dump_stack);
 176
 177 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 178 {
 179         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 180 }
 181
 182 void show_registers(struct pt_regs *regs)
 183 {
 184         char *mode;
 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("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 192                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 193                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 194                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 195                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 196                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 197                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 198 #ifdef CONFIG_64BIT
 199         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 200 #endif
 201         printk("\n%s GPRS: " FOURLONG, mode,
 202                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 203         printk("           " FOURLONG,
 204                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 205         printk("           " FOURLONG,
 206                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 207         printk("           " FOURLONG,
 208                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 209
 210         show_code(regs);
 211 }
 212
 213 /* This is called from fs/proc/array.c */
 214 char *task_show_regs(struct task_struct *task, char *buffer)
 215 {
 216         struct pt_regs *regs;
 217
 218         regs = task_pt_regs(task);
 219         buffer += sprintf(buffer, "task: %p, ksp: %p\n",
 220                        task, (void *)task->thread.ksp);
 221         buffer += sprintf(buffer, "User PSW : %p %p\n",
 222                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 223
 224         buffer += sprintf(buffer, "User GPRS: " FOURLONG,
 225                           regs->gprs[0], regs->gprs[1],
 226                           regs->gprs[2], regs->gprs[3]);
 227         buffer += sprintf(buffer, "           " FOURLONG,
 228                           regs->gprs[4], regs->gprs[5],
 229                           regs->gprs[6], regs->gprs[7]);
 230         buffer += sprintf(buffer, "           " FOURLONG,
 231                           regs->gprs[8], regs->gprs[9],
 232                           regs->gprs[10], regs->gprs[11]);
 233         buffer += sprintf(buffer, "           " FOURLONG,
 234                           regs->gprs[12], regs->gprs[13],
 235                           regs->gprs[14], regs->gprs[15]);
 236         buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
 237                           task->thread.acrs[0], task->thread.acrs[1],
 238                           task->thread.acrs[2], task->thread.acrs[3]);
 239         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 240                           task->thread.acrs[4], task->thread.acrs[5],
 241                           task->thread.acrs[6], task->thread.acrs[7]);
 242         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 243                           task->thread.acrs[8], task->thread.acrs[9],
 244                           task->thread.acrs[10], task->thread.acrs[11]);
 245         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 246                           task->thread.acrs[12], task->thread.acrs[13],
 247                           task->thread.acrs[14], task->thread.acrs[15]);
 248         return buffer;
 249 }
 250
 251 static DEFINE_SPINLOCK(die_lock);
 252
 253 void die(const char * str, struct pt_regs * regs, long err)
 254 {
 255         static int die_counter;
 256
 257         debug_stop_all();
 258         console_verbose();
 259         spin_lock_irq(&die_lock);
 260         bust_spinlocks(1);
 261         printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 262         show_regs(regs);
 263         bust_spinlocks(0);
 264         spin_unlock_irq(&die_lock);
 265         if (in_interrupt())
 266                 panic("Fatal exception in interrupt");
 267         if (panic_on_oops)
 268                 panic("Fatal exception: panic_on_oops");
 269         do_exit(SIGSEGV);
 270 }
 271
 272 static void inline
 273 report_user_fault(long interruption_code, struct pt_regs *regs)
 274 {
 275 #if defined(CONFIG_SYSCTL)
 276         if (!sysctl_userprocess_debug)
 277                 return;
 278 #endif
 279 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 280         printk("User process fault: interruption code 0x%lX\n",
 281                interruption_code);
 282         show_regs(regs);
 283 #endif
 284 }
 285
 286 int is_valid_bugaddr(unsigned long addr)
 287 {
 288         return 1;
 289 }
 290
 291 static void __kprobes inline do_trap(long interruption_code, int signr,
 292                                         char *str, struct pt_regs *regs,
 293                                         siginfo_t *info)
 294 {
 295         /*
 296          * We got all needed information from the lowcore and can
 297          * now safely switch on interrupts.
 298          */
 299         if (regs->psw.mask & PSW_MASK_PSTATE)
 300                 local_irq_enable();
 301
 302         if (notify_die(DIE_TRAP, str, regs, interruption_code,
 303                                 interruption_code, signr) == NOTIFY_STOP)
 304                 return;
 305
 306         if (regs->psw.mask & PSW_MASK_PSTATE) {
 307                 struct task_struct *tsk = current;
 308
 309                 tsk->thread.trap_no = interruption_code & 0xffff;
 310                 force_sig_info(signr, info, tsk);
 311                 report_user_fault(interruption_code, regs);
 312         } else {
 313                 const struct exception_table_entry *fixup;
 314                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 315                 if (fixup)
 316                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 317                 else {
 318                         enum bug_trap_type btt;
 319
 320                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN);
 321                         if (btt == BUG_TRAP_TYPE_WARN)
 322                                 return;
 323                         die(str, regs, interruption_code);
 324                 }
 325         }
 326 }
 327
 328 static inline void __user *get_check_address(struct pt_regs *regs)
 329 {
 330         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 331 }
 332
 333 void __kprobes do_single_step(struct pt_regs *regs)
 334 {
 335         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 336                                         SIGTRAP) == NOTIFY_STOP){
 337                 return;
 338         }
 339         if ((current->ptrace & PT_PTRACED) != 0)
 340                 force_sig(SIGTRAP, current);
 341 }
 342
 343 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 344 {
 345         if (regs->psw.mask & PSW_MASK_PSTATE) {
 346                 local_irq_enable();
 347                 do_exit(SIGSEGV);
 348                 report_user_fault(interruption_code, regs);
 349         } else
 350                 die("Unknown program exception", regs, interruption_code);
 351 }
 352
 353 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 354 static void name(struct pt_regs * regs, long interruption_code) \
 355 { \
 356         siginfo_t info; \
 357         info.si_signo = signr; \
 358         info.si_errno = 0; \
 359         info.si_code = sicode; \
 360         info.si_addr = siaddr; \
 361         do_trap(interruption_code, signr, str, regs, &info); \
 362 }
 363
 364 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 365               ILL_ILLADR, get_check_address(regs))
 366 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 367               ILL_ILLOPN, get_check_address(regs))
 368 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 369               FPE_INTDIV, get_check_address(regs))
 370 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 371               FPE_INTOVF, get_check_address(regs))
 372 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 373               FPE_FLTOVF, get_check_address(regs))
 374 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 375               FPE_FLTUND, get_check_address(regs))
 376 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 377               FPE_FLTRES, get_check_address(regs))
 378 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 379               FPE_FLTDIV, get_check_address(regs))
 380 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 381               FPE_FLTINV, get_check_address(regs))
 382 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 383               ILL_ILLOPN, get_check_address(regs))
 384 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 385               ILL_PRVOPC, get_check_address(regs))
 386 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 387               ILL_ILLOPN, get_check_address(regs))
 388 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 389               ILL_ILLOPN, get_check_address(regs))
 390
 391 static inline void
 392 do_fp_trap(struct pt_regs *regs, void __user *location,
 393            int fpc, long interruption_code)
 394 {
 395         siginfo_t si;
 396
 397         si.si_signo = SIGFPE;
 398         si.si_errno = 0;
 399         si.si_addr = location;
 400         si.si_code = 0;
 401         /* FPC[2] is Data Exception Code */
 402         if ((fpc & 0x00000300) == 0) {
 403                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 404                 if (fpc & 0x8000) /* invalid fp operation */
 405                         si.si_code = FPE_FLTINV;
 406                 else if (fpc & 0x4000) /* div by 0 */
 407                         si.si_code = FPE_FLTDIV;
 408                 else if (fpc & 0x2000) /* overflow */
 409                         si.si_code = FPE_FLTOVF;
 410                 else if (fpc & 0x1000) /* underflow */
 411                         si.si_code = FPE_FLTUND;
 412                 else if (fpc & 0x0800) /* inexact */
 413                         si.si_code = FPE_FLTRES;
 414         }
 415         current->thread.ieee_instruction_pointer = (addr_t) location;
 416         do_trap(interruption_code, SIGFPE,
 417                 "floating point exception", regs, &si);
 418 }
 419
 420 static void illegal_op(struct pt_regs * regs, long interruption_code)
 421 {
 422         siginfo_t info;
 423         __u8 opcode[6];
 424         __u16 __user *location;
 425         int signal = 0;
 426
 427         location = 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                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 438                         return;
 439                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 440                         if (current->ptrace & PT_PTRACED)
 441                                 force_sig(SIGTRAP, current);
 442                         else
 443                                 signal = SIGILL;
 444 #ifdef CONFIG_MATHEMU
 445                 } else if (opcode[0] == 0xb3) {
 446                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 447                                 return;
 448                         signal = math_emu_b3(opcode, regs);
 449                 } else if (opcode[0] == 0xed) {
 450                         if (get_user(*((__u32 *) (opcode+2)),
 451                                      (__u32 __user *)(location+1)))
 452                                 return;
 453                         signal = math_emu_ed(opcode, regs);
 454                 } else if (*((__u16 *) opcode) == 0xb299) {
 455                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 456                                 return;
 457                         signal = math_emu_srnm(opcode, regs);
 458                 } else if (*((__u16 *) opcode) == 0xb29c) {
 459                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 460                                 return;
 461                         signal = math_emu_stfpc(opcode, regs);
 462                 } else if (*((__u16 *) opcode) == 0xb29d) {
 463                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 464                                 return;
 465                         signal = math_emu_lfpc(opcode, regs);
 466 #endif
 467                 } else
 468                         signal = SIGILL;
 469         } else {
 470                 /*
 471                  * If we get an illegal op in kernel mode, send it through the
 472                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 473                  */
 474                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 475                                3, SIGTRAP) != NOTIFY_STOP)
 476                         signal = SIGILL;
 477         }
 478
 479 #ifdef CONFIG_MATHEMU
 480         if (signal == SIGFPE)
 481                 do_fp_trap(regs, location,
 482                            current->thread.fp_regs.fpc, interruption_code);
 483         else if (signal == SIGSEGV) {
 484                 info.si_signo = signal;
 485                 info.si_errno = 0;
 486                 info.si_code = SEGV_MAPERR;
 487                 info.si_addr = (void __user *) location;
 488                 do_trap(interruption_code, signal,
 489                         "user address fault", regs, &info);
 490         } else
 491 #endif
 492         if (signal) {
 493                 info.si_signo = signal;
 494                 info.si_errno = 0;
 495                 info.si_code = ILL_ILLOPC;
 496                 info.si_addr = (void __user *) location;
 497                 do_trap(interruption_code, signal,
 498                         "illegal operation", regs, &info);
 499         }
 500 }
 501
 502
 503 #ifdef CONFIG_MATHEMU
 504 asmlinkage void
 505 specification_exception(struct pt_regs * regs, long interruption_code)
 506 {
 507         __u8 opcode[6];
 508         __u16 __user *location = NULL;
 509         int signal = 0;
 510
 511         location = (__u16 __user *) get_check_address(regs);
 512
 513         /*
 514          * We got all needed information from the lowcore and can
 515          * now safely switch on interrupts.
 516          */
 517         if (regs->psw.mask & PSW_MASK_PSTATE)
 518                 local_irq_enable();
 519
 520         if (regs->psw.mask & PSW_MASK_PSTATE) {
 521                 get_user(*((__u16 *) opcode), location);
 522                 switch (opcode[0]) {
 523                 case 0x28: /* LDR Rx,Ry   */
 524                         signal = math_emu_ldr(opcode);
 525                         break;
 526                 case 0x38: /* LER Rx,Ry   */
 527                         signal = math_emu_ler(opcode);
 528                         break;
 529                 case 0x60: /* STD R,D(X,B) */
 530                         get_user(*((__u16 *) (opcode+2)), location+1);
 531                         signal = math_emu_std(opcode, regs);
 532                         break;
 533                 case 0x68: /* LD R,D(X,B) */
 534                         get_user(*((__u16 *) (opcode+2)), location+1);
 535                         signal = math_emu_ld(opcode, regs);
 536                         break;
 537                 case 0x70: /* STE R,D(X,B) */
 538                         get_user(*((__u16 *) (opcode+2)), location+1);
 539                         signal = math_emu_ste(opcode, regs);
 540                         break;
 541                 case 0x78: /* LE R,D(X,B) */
 542                         get_user(*((__u16 *) (opcode+2)), location+1);
 543                         signal = math_emu_le(opcode, regs);
 544                         break;
 545                 default:
 546                         signal = SIGILL;
 547                         break;
 548                 }
 549         } else
 550                 signal = SIGILL;
 551
 552         if (signal == SIGFPE)
 553                 do_fp_trap(regs, location,
 554                            current->thread.fp_regs.fpc, interruption_code);
 555         else if (signal) {
 556                 siginfo_t info;
 557                 info.si_signo = signal;
 558                 info.si_errno = 0;
 559                 info.si_code = ILL_ILLOPN;
 560                 info.si_addr = location;
 561                 do_trap(interruption_code, signal,
 562                         "specification exception", regs, &info);
 563         }
 564 }
 565 #else
 566 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 567               ILL_ILLOPN, get_check_address(regs));
 568 #endif
 569
 570 static void data_exception(struct pt_regs * regs, long interruption_code)
 571 {
 572         __u16 __user *location;
 573         int signal = 0;
 574
 575         location = get_check_address(regs);
 576
 577         /*
 578          * We got all needed information from the lowcore and can
 579          * now safely switch on interrupts.
 580          */
 581         if (regs->psw.mask & PSW_MASK_PSTATE)
 582                 local_irq_enable();
 583
 584         if (MACHINE_HAS_IEEE)
 585                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 586
 587 #ifdef CONFIG_MATHEMU
 588         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 589                 __u8 opcode[6];
 590                 get_user(*((__u16 *) opcode), location);
 591                 switch (opcode[0]) {
 592                 case 0x28: /* LDR Rx,Ry   */
 593                         signal = math_emu_ldr(opcode);
 594                         break;
 595                 case 0x38: /* LER Rx,Ry   */
 596                         signal = math_emu_ler(opcode);
 597                         break;
 598                 case 0x60: /* STD R,D(X,B) */
 599                         get_user(*((__u16 *) (opcode+2)), location+1);
 600                         signal = math_emu_std(opcode, regs);
 601                         break;
 602                 case 0x68: /* LD R,D(X,B) */
 603                         get_user(*((__u16 *) (opcode+2)), location+1);
 604                         signal = math_emu_ld(opcode, regs);
 605                         break;
 606                 case 0x70: /* STE R,D(X,B) */
 607                         get_user(*((__u16 *) (opcode+2)), location+1);
 608                         signal = math_emu_ste(opcode, regs);
 609                         break;
 610                 case 0x78: /* LE R,D(X,B) */
 611                         get_user(*((__u16 *) (opcode+2)), location+1);
 612                         signal = math_emu_le(opcode, regs);
 613                         break;
 614                 case 0xb3:
 615                         get_user(*((__u16 *) (opcode+2)), location+1);
 616                         signal = math_emu_b3(opcode, regs);
 617                         break;
 618                 case 0xed:
 619                         get_user(*((__u32 *) (opcode+2)),
 620                                  (__u32 __user *)(location+1));
 621                         signal = math_emu_ed(opcode, regs);
 622                         break;
 623                 case 0xb2:
 624                         if (opcode[1] == 0x99) {
 625                                 get_user(*((__u16 *) (opcode+2)), location+1);
 626                                 signal = math_emu_srnm(opcode, regs);
 627                         } else if (opcode[1] == 0x9c) {
 628                                 get_user(*((__u16 *) (opcode+2)), location+1);
 629                                 signal = math_emu_stfpc(opcode, regs);
 630                         } else if (opcode[1] == 0x9d) {
 631                                 get_user(*((__u16 *) (opcode+2)), location+1);
 632                                 signal = math_emu_lfpc(opcode, regs);
 633                         } else
 634                                 signal = SIGILL;
 635                         break;
 636                 default:
 637                         signal = SIGILL;
 638                         break;
 639                 }
 640         }
 641 #endif
 642         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 643                 signal = SIGFPE;
 644         else
 645                 signal = SIGILL;
 646         if (signal == SIGFPE)
 647                 do_fp_trap(regs, location,
 648                            current->thread.fp_regs.fpc, interruption_code);
 649         else if (signal) {
 650                 siginfo_t info;
 651                 info.si_signo = signal;
 652                 info.si_errno = 0;
 653                 info.si_code = ILL_ILLOPN;
 654                 info.si_addr = location;
 655                 do_trap(interruption_code, signal,
 656                         "data exception", regs, &info);
 657         }
 658 }
 659
 660 static void space_switch_exception(struct pt_regs * regs, long int_code)
 661 {
 662         siginfo_t info;
 663
 664         /* Set user psw back to home space mode. */
 665         if (regs->psw.mask & PSW_MASK_PSTATE)
 666                 regs->psw.mask |= PSW_ASC_HOME;
 667         /* Send SIGILL. */
 668         info.si_signo = SIGILL;
 669         info.si_errno = 0;
 670         info.si_code = ILL_PRVOPC;
 671         info.si_addr = get_check_address(regs);
 672         do_trap(int_code, SIGILL, "space switch event", regs, &info);
 673 }
 674
 675 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 676 {
 677         bust_spinlocks(1);
 678         printk("Kernel stack overflow.\n");
 679         show_regs(regs);
 680         bust_spinlocks(0);
 681         panic("Corrupt kernel stack, can't continue.");
 682 }
 683
 684 /* init is done in lowcore.S and head.S */
 685
 686 void __init trap_init(void)
 687 {
 688         int i;
 689
 690         for (i = 0; i < 128; i++)
 691           pgm_check_table[i] = &default_trap_handler;
 692         pgm_check_table[1] = &illegal_op;
 693         pgm_check_table[2] = &privileged_op;
 694         pgm_check_table[3] = &execute_exception;
 695         pgm_check_table[4] = &do_protection_exception;
 696         pgm_check_table[5] = &addressing_exception;
 697         pgm_check_table[6] = &specification_exception;
 698         pgm_check_table[7] = &data_exception;
 699         pgm_check_table[8] = &overflow_exception;
 700         pgm_check_table[9] = &divide_exception;
 701         pgm_check_table[0x0A] = &overflow_exception;
 702         pgm_check_table[0x0B] = &divide_exception;
 703         pgm_check_table[0x0C] = &hfp_overflow_exception;
 704         pgm_check_table[0x0D] = &hfp_underflow_exception;
 705         pgm_check_table[0x0E] = &hfp_significance_exception;
 706         pgm_check_table[0x0F] = &hfp_divide_exception;
 707         pgm_check_table[0x10] = &do_dat_exception;
 708         pgm_check_table[0x11] = &do_dat_exception;
 709         pgm_check_table[0x12] = &translation_exception;
 710         pgm_check_table[0x13] = &special_op_exception;
 711 #ifdef CONFIG_64BIT
 712         pgm_check_table[0x38] = &do_dat_exception;
 713         pgm_check_table[0x39] = &do_dat_exception;
 714         pgm_check_table[0x3A] = &do_dat_exception;
 715         pgm_check_table[0x3B] = &do_dat_exception;
 716 #endif /* CONFIG_64BIT */
 717         pgm_check_table[0x15] = &operand_exception;
 718         pgm_check_table[0x1C] = &space_switch_exception;
 719         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 720         pgm_check_table[0x40] = &do_monitor_call;
 721         pfault_irq_init();
 722 }