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/kallsyms.h>
  31 #include <linux/reboot.h>
  32 #include <linux/kprobes.h>
  33
  34 #include <asm/system.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/io.h>
  37 #include <asm/atomic.h>
  38 #include <asm/mathemu.h>
  39 #include <asm/cpcmd.h>
  40 #include <asm/s390_ext.h>
  41 #include <asm/lowcore.h>
  42 #include <asm/debug.h>
  43 #include <asm/kdebug.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 ATOMIC_NOTIFIER_HEAD(s390die_chain);
  74
  75 int register_die_notifier(struct notifier_block *nb)
  76 {
  77         return atomic_notifier_chain_register(&s390die_chain, nb);
  78 }
  79 EXPORT_SYMBOL(register_die_notifier);
  80
  81 int unregister_die_notifier(struct notifier_block *nb)
  82 {
  83         return atomic_notifier_chain_unregister(&s390die_chain, nb);
  84 }
  85 EXPORT_SYMBOL(unregister_die_notifier);
  86
  87 /*
  88  * For show_trace we have tree different stack to consider:
  89  *   - the panic stack which is used if the kernel stack has overflown
  90  *   - the asynchronous interrupt stack (cpu related)
  91  *   - the synchronous kernel stack (process related)
  92  * The stack trace can start at any of the three stack and can potentially
  93  * touch all of them. The order is: panic stack, async stack, sync stack.
  94  */
  95 static unsigned long
  96 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  97 {
  98         struct stack_frame *sf;
  99         struct pt_regs *regs;
 100
 101         while (1) {
 102                 sp = sp & PSW_ADDR_INSN;
 103                 if (sp < low || sp > high - sizeof(*sf))
 104                         return sp;
 105                 sf = (struct stack_frame *) sp;
 106                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 107                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
 108                 /* Follow the backchain. */
 109                 while (1) {
 110                         low = sp;
 111                         sp = sf->back_chain & PSW_ADDR_INSN;
 112                         if (!sp)
 113                                 break;
 114                         if (sp <= low || sp > high - sizeof(*sf))
 115                                 return sp;
 116                         sf = (struct stack_frame *) sp;
 117                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 118                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 119                 }
 120                 /* Zero backchain detected, check for interrupt frame. */
 121                 sp = (unsigned long) (sf + 1);
 122                 if (sp <= low || sp > high - sizeof(*regs))
 123                         return sp;
 124                 regs = (struct pt_regs *) sp;
 125                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 126                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 127                 low = sp;
 128                 sp = regs->gprs[15];
 129         }
 130 }
 131
 132 void show_trace(struct task_struct *task, unsigned long *stack)
 133 {
 134         register unsigned long __r15 asm ("15");
 135         unsigned long sp;
 136
 137         sp = (unsigned long) stack;
 138         if (!sp)
 139                 sp = task ? task->thread.ksp : __r15;
 140         printk("Call Trace:\n");
 141 #ifdef CONFIG_CHECK_STACK
 142         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 143                           S390_lowcore.panic_stack);
 144 #endif
 145         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 146                           S390_lowcore.async_stack);
 147         if (task)
 148                 __show_trace(sp, (unsigned long) task_stack_page(task),
 149                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
 150         else
 151                 __show_trace(sp, S390_lowcore.thread_info,
 152                              S390_lowcore.thread_info + THREAD_SIZE);
 153         printk("\n");
 154         if (!task)
 155                 task = current;
 156         debug_show_held_locks(task);
 157 }
 158
 159 void show_stack(struct task_struct *task, unsigned long *sp)
 160 {
 161         register unsigned long * __r15 asm ("15");
 162         unsigned long *stack;
 163         int i;
 164
 165         if (!sp)
 166                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
 167         else
 168                 stack = sp;
 169
 170         for (i = 0; i < kstack_depth_to_print; i++) {
 171                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 172                         break;
 173                 if (i && ((i * sizeof (long) % 32) == 0))
 174                         printk("\n       ");
 175                 printk("%p ", (void *)*stack++);
 176         }
 177         printk("\n");
 178         show_trace(task, sp);
 179 }
 180
 181 /*
 182  * The architecture-independent dump_stack generator
 183  */
 184 void dump_stack(void)
 185 {
 186         show_stack(NULL, NULL);
 187 }
 188
 189 EXPORT_SYMBOL(dump_stack);
 190
 191 void show_registers(struct pt_regs *regs)
 192 {
 193         mm_segment_t old_fs;
 194         char *mode;
 195         int i;
 196
 197         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 198         printk("%s PSW : %p %p",
 199                mode, (void *) regs->psw.mask,
 200                (void *) regs->psw.addr);
 201         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 202         printk("%s GPRS: " FOURLONG, mode,
 203                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 204         printk("           " FOURLONG,
 205                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 206         printk("           " FOURLONG,
 207                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 208         printk("           " FOURLONG,
 209                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 210
 211 #if 0
 212         /* FIXME: this isn't needed any more but it changes the ksymoops
 213          * input. To remove or not to remove ... */
 214         save_access_regs(regs->acrs);
 215         printk("%s ACRS: %08x %08x %08x %08x\n", mode,
 216                regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
 217         printk("           %08x %08x %08x %08x\n",
 218                regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
 219         printk("           %08x %08x %08x %08x\n",
 220                regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
 221         printk("           %08x %08x %08x %08x\n",
 222                regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
 223 #endif
 224
 225         /*
 226          * Print the first 20 byte of the instruction stream at the
 227          * time of the fault.
 228          */
 229         old_fs = get_fs();
 230         if (regs->psw.mask & PSW_MASK_PSTATE)
 231                 set_fs(USER_DS);
 232         else
 233                 set_fs(KERNEL_DS);
 234         printk("%s Code: ", mode);
 235         for (i = 0; i < 20; i++) {
 236                 unsigned char c;
 237                 if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
 238                         printk(" Bad PSW.");
 239                         break;
 240                 }
 241                 printk("%02x ", c);
 242         }
 243         set_fs(old_fs);
 244
 245         printk("\n");
 246 }
 247
 248 /* This is called from fs/proc/array.c */
 249 char *task_show_regs(struct task_struct *task, char *buffer)
 250 {
 251         struct pt_regs *regs;
 252
 253         regs = task_pt_regs(task);
 254         buffer += sprintf(buffer, "task: %p, ksp: %p\n",
 255                        task, (void *)task->thread.ksp);
 256         buffer += sprintf(buffer, "User PSW : %p %p\n",
 257                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 258
 259         buffer += sprintf(buffer, "User GPRS: " FOURLONG,
 260                           regs->gprs[0], regs->gprs[1],
 261                           regs->gprs[2], regs->gprs[3]);
 262         buffer += sprintf(buffer, "           " FOURLONG,
 263                           regs->gprs[4], regs->gprs[5],
 264                           regs->gprs[6], regs->gprs[7]);
 265         buffer += sprintf(buffer, "           " FOURLONG,
 266                           regs->gprs[8], regs->gprs[9],
 267                           regs->gprs[10], regs->gprs[11]);
 268         buffer += sprintf(buffer, "           " FOURLONG,
 269                           regs->gprs[12], regs->gprs[13],
 270                           regs->gprs[14], regs->gprs[15]);
 271         buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
 272                           task->thread.acrs[0], task->thread.acrs[1],
 273                           task->thread.acrs[2], task->thread.acrs[3]);
 274         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 275                           task->thread.acrs[4], task->thread.acrs[5],
 276                           task->thread.acrs[6], task->thread.acrs[7]);
 277         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 278                           task->thread.acrs[8], task->thread.acrs[9],
 279                           task->thread.acrs[10], task->thread.acrs[11]);
 280         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 281                           task->thread.acrs[12], task->thread.acrs[13],
 282                           task->thread.acrs[14], task->thread.acrs[15]);
 283         return buffer;
 284 }
 285
 286 static DEFINE_SPINLOCK(die_lock);
 287
 288 void die(const char * str, struct pt_regs * regs, long err)
 289 {
 290         static int die_counter;
 291
 292         debug_stop_all();
 293         console_verbose();
 294         spin_lock_irq(&die_lock);
 295         bust_spinlocks(1);
 296         printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 297         show_regs(regs);
 298         bust_spinlocks(0);
 299         spin_unlock_irq(&die_lock);
 300         if (in_interrupt())
 301                 panic("Fatal exception in interrupt");
 302         if (panic_on_oops)
 303                 panic("Fatal exception: panic_on_oops");
 304         do_exit(SIGSEGV);
 305 }
 306
 307 static void inline
 308 report_user_fault(long interruption_code, struct pt_regs *regs)
 309 {
 310 #if defined(CONFIG_SYSCTL)
 311         if (!sysctl_userprocess_debug)
 312                 return;
 313 #endif
 314 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 315         printk("User process fault: interruption code 0x%lX\n",
 316                interruption_code);
 317         show_regs(regs);
 318 #endif
 319 }
 320
 321 static void __kprobes inline do_trap(long interruption_code, int signr,
 322                                         char *str, struct pt_regs *regs,
 323                                         siginfo_t *info)
 324 {
 325         /*
 326          * We got all needed information from the lowcore and can
 327          * now safely switch on interrupts.
 328          */
 329         if (regs->psw.mask & PSW_MASK_PSTATE)
 330                 local_irq_enable();
 331
 332         if (notify_die(DIE_TRAP, str, regs, interruption_code,
 333                                 interruption_code, signr) == NOTIFY_STOP)
 334                 return;
 335
 336         if (regs->psw.mask & PSW_MASK_PSTATE) {
 337                 struct task_struct *tsk = current;
 338
 339                 tsk->thread.trap_no = interruption_code & 0xffff;
 340                 force_sig_info(signr, info, tsk);
 341                 report_user_fault(interruption_code, regs);
 342         } else {
 343                 const struct exception_table_entry *fixup;
 344                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 345                 if (fixup)
 346                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 347                 else
 348                         die(str, regs, interruption_code);
 349         }
 350 }
 351
 352 static inline void __user *get_check_address(struct pt_regs *regs)
 353 {
 354         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 355 }
 356
 357 void __kprobes do_single_step(struct pt_regs *regs)
 358 {
 359         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 360                                         SIGTRAP) == NOTIFY_STOP){
 361                 return;
 362         }
 363         if ((current->ptrace & PT_PTRACED) != 0)
 364                 force_sig(SIGTRAP, current);
 365 }
 366
 367 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 368 {
 369         if (regs->psw.mask & PSW_MASK_PSTATE) {
 370                 local_irq_enable();
 371                 do_exit(SIGSEGV);
 372                 report_user_fault(interruption_code, regs);
 373         } else
 374                 die("Unknown program exception", regs, interruption_code);
 375 }
 376
 377 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 378 static void name(struct pt_regs * regs, long interruption_code) \
 379 { \
 380         siginfo_t info; \
 381         info.si_signo = signr; \
 382         info.si_errno = 0; \
 383         info.si_code = sicode; \
 384         info.si_addr = siaddr; \
 385         do_trap(interruption_code, signr, str, regs, &info); \
 386 }
 387
 388 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 389               ILL_ILLADR, get_check_address(regs))
 390 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 391               ILL_ILLOPN, get_check_address(regs))
 392 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 393               FPE_INTDIV, get_check_address(regs))
 394 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 395               FPE_INTOVF, get_check_address(regs))
 396 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 397               FPE_FLTOVF, get_check_address(regs))
 398 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 399               FPE_FLTUND, get_check_address(regs))
 400 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 401               FPE_FLTRES, get_check_address(regs))
 402 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 403               FPE_FLTDIV, get_check_address(regs))
 404 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 405               FPE_FLTINV, get_check_address(regs))
 406 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 407               ILL_ILLOPN, get_check_address(regs))
 408 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 409               ILL_PRVOPC, get_check_address(regs))
 410 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 411               ILL_ILLOPN, get_check_address(regs))
 412 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 413               ILL_ILLOPN, get_check_address(regs))
 414
 415 static inline void
 416 do_fp_trap(struct pt_regs *regs, void __user *location,
 417            int fpc, long interruption_code)
 418 {
 419         siginfo_t si;
 420
 421         si.si_signo = SIGFPE;
 422         si.si_errno = 0;
 423         si.si_addr = location;
 424         si.si_code = 0;
 425         /* FPC[2] is Data Exception Code */
 426         if ((fpc & 0x00000300) == 0) {
 427                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 428                 if (fpc & 0x8000) /* invalid fp operation */
 429                         si.si_code = FPE_FLTINV;
 430                 else if (fpc & 0x4000) /* div by 0 */
 431                         si.si_code = FPE_FLTDIV;
 432                 else if (fpc & 0x2000) /* overflow */
 433                         si.si_code = FPE_FLTOVF;
 434                 else if (fpc & 0x1000) /* underflow */
 435                         si.si_code = FPE_FLTUND;
 436                 else if (fpc & 0x0800) /* inexact */
 437                         si.si_code = FPE_FLTRES;
 438         }
 439         current->thread.ieee_instruction_pointer = (addr_t) location;
 440         do_trap(interruption_code, SIGFPE,
 441                 "floating point exception", regs, &si);
 442 }
 443
 444 static void illegal_op(struct pt_regs * regs, long interruption_code)
 445 {
 446         siginfo_t info;
 447         __u8 opcode[6];
 448         __u16 __user *location;
 449         int signal = 0;
 450
 451         location = get_check_address(regs);
 452
 453         /*
 454          * We got all needed information from the lowcore and can
 455          * now safely switch on interrupts.
 456          */
 457         if (regs->psw.mask & PSW_MASK_PSTATE)
 458                 local_irq_enable();
 459
 460         if (regs->psw.mask & PSW_MASK_PSTATE) {
 461                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 462                         return;
 463                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 464                         if (current->ptrace & PT_PTRACED)
 465                                 force_sig(SIGTRAP, current);
 466                         else
 467                                 signal = SIGILL;
 468 #ifdef CONFIG_MATHEMU
 469                 } else if (opcode[0] == 0xb3) {
 470                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 471                                 return;
 472                         signal = math_emu_b3(opcode, regs);
 473                 } else if (opcode[0] == 0xed) {
 474                         if (get_user(*((__u32 *) (opcode+2)),
 475                                      (__u32 __user *)(location+1)))
 476                                 return;
 477                         signal = math_emu_ed(opcode, regs);
 478                 } else if (*((__u16 *) opcode) == 0xb299) {
 479                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 480                                 return;
 481                         signal = math_emu_srnm(opcode, regs);
 482                 } else if (*((__u16 *) opcode) == 0xb29c) {
 483                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 484                                 return;
 485                         signal = math_emu_stfpc(opcode, regs);
 486                 } else if (*((__u16 *) opcode) == 0xb29d) {
 487                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 488                                 return;
 489                         signal = math_emu_lfpc(opcode, regs);
 490 #endif
 491                 } else
 492                         signal = SIGILL;
 493         } else {
 494                 /*
 495                  * If we get an illegal op in kernel mode, send it through the
 496                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 497                  */
 498                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 499                                3, SIGTRAP) != NOTIFY_STOP)
 500                         signal = SIGILL;
 501         }
 502
 503 #ifdef CONFIG_MATHEMU
 504         if (signal == SIGFPE)
 505                 do_fp_trap(regs, location,
 506                            current->thread.fp_regs.fpc, interruption_code);
 507         else if (signal == SIGSEGV) {
 508                 info.si_signo = signal;
 509                 info.si_errno = 0;
 510                 info.si_code = SEGV_MAPERR;
 511                 info.si_addr = (void __user *) location;
 512                 do_trap(interruption_code, signal,
 513                         "user address fault", regs, &info);
 514         } else
 515 #endif
 516         if (signal) {
 517                 info.si_signo = signal;
 518                 info.si_errno = 0;
 519                 info.si_code = ILL_ILLOPC;
 520                 info.si_addr = (void __user *) location;
 521                 do_trap(interruption_code, signal,
 522                         "illegal operation", regs, &info);
 523         }
 524 }
 525
 526
 527 #ifdef CONFIG_MATHEMU
 528 asmlinkage void
 529 specification_exception(struct pt_regs * regs, long interruption_code)
 530 {
 531         __u8 opcode[6];
 532         __u16 __user *location = NULL;
 533         int signal = 0;
 534
 535         location = (__u16 __user *) get_check_address(regs);
 536
 537         /*
 538          * We got all needed information from the lowcore and can
 539          * now safely switch on interrupts.
 540          */
 541         if (regs->psw.mask & PSW_MASK_PSTATE)
 542                 local_irq_enable();
 543
 544         if (regs->psw.mask & PSW_MASK_PSTATE) {
 545                 get_user(*((__u16 *) opcode), location);
 546                 switch (opcode[0]) {
 547                 case 0x28: /* LDR Rx,Ry   */
 548                         signal = math_emu_ldr(opcode);
 549                         break;
 550                 case 0x38: /* LER Rx,Ry   */
 551                         signal = math_emu_ler(opcode);
 552                         break;
 553                 case 0x60: /* STD R,D(X,B) */
 554                         get_user(*((__u16 *) (opcode+2)), location+1);
 555                         signal = math_emu_std(opcode, regs);
 556                         break;
 557                 case 0x68: /* LD R,D(X,B) */
 558                         get_user(*((__u16 *) (opcode+2)), location+1);
 559                         signal = math_emu_ld(opcode, regs);
 560                         break;
 561                 case 0x70: /* STE R,D(X,B) */
 562                         get_user(*((__u16 *) (opcode+2)), location+1);
 563                         signal = math_emu_ste(opcode, regs);
 564                         break;
 565                 case 0x78: /* LE R,D(X,B) */
 566                         get_user(*((__u16 *) (opcode+2)), location+1);
 567                         signal = math_emu_le(opcode, regs);
 568                         break;
 569                 default:
 570                         signal = SIGILL;
 571                         break;
 572                 }
 573         } else
 574                 signal = SIGILL;
 575
 576         if (signal == SIGFPE)
 577                 do_fp_trap(regs, location,
 578                            current->thread.fp_regs.fpc, interruption_code);
 579         else if (signal) {
 580                 siginfo_t info;
 581                 info.si_signo = signal;
 582                 info.si_errno = 0;
 583                 info.si_code = ILL_ILLOPN;
 584                 info.si_addr = location;
 585                 do_trap(interruption_code, signal,
 586                         "specification exception", regs, &info);
 587         }
 588 }
 589 #else
 590 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 591               ILL_ILLOPN, get_check_address(regs));
 592 #endif
 593
 594 static void data_exception(struct pt_regs * regs, long interruption_code)
 595 {
 596         __u16 __user *location;
 597         int signal = 0;
 598
 599         location = get_check_address(regs);
 600
 601         /*
 602          * We got all needed information from the lowcore and can
 603          * now safely switch on interrupts.
 604          */
 605         if (regs->psw.mask & PSW_MASK_PSTATE)
 606                 local_irq_enable();
 607
 608         if (MACHINE_HAS_IEEE)
 609                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 610
 611 #ifdef CONFIG_MATHEMU
 612         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 613                 __u8 opcode[6];
 614                 get_user(*((__u16 *) opcode), location);
 615                 switch (opcode[0]) {
 616                 case 0x28: /* LDR Rx,Ry   */
 617                         signal = math_emu_ldr(opcode);
 618                         break;
 619                 case 0x38: /* LER Rx,Ry   */
 620                         signal = math_emu_ler(opcode);
 621                         break;
 622                 case 0x60: /* STD R,D(X,B) */
 623                         get_user(*((__u16 *) (opcode+2)), location+1);
 624                         signal = math_emu_std(opcode, regs);
 625                         break;
 626                 case 0x68: /* LD R,D(X,B) */
 627                         get_user(*((__u16 *) (opcode+2)), location+1);
 628                         signal = math_emu_ld(opcode, regs);
 629                         break;
 630                 case 0x70: /* STE R,D(X,B) */
 631                         get_user(*((__u16 *) (opcode+2)), location+1);
 632                         signal = math_emu_ste(opcode, regs);
 633                         break;
 634                 case 0x78: /* LE R,D(X,B) */
 635                         get_user(*((__u16 *) (opcode+2)), location+1);
 636                         signal = math_emu_le(opcode, regs);
 637                         break;
 638                 case 0xb3:
 639                         get_user(*((__u16 *) (opcode+2)), location+1);
 640                         signal = math_emu_b3(opcode, regs);
 641                         break;
 642                 case 0xed:
 643                         get_user(*((__u32 *) (opcode+2)),
 644                                  (__u32 __user *)(location+1));
 645                         signal = math_emu_ed(opcode, regs);
 646                         break;
 647                 case 0xb2:
 648                         if (opcode[1] == 0x99) {
 649                                 get_user(*((__u16 *) (opcode+2)), location+1);
 650                                 signal = math_emu_srnm(opcode, regs);
 651                         } else if (opcode[1] == 0x9c) {
 652                                 get_user(*((__u16 *) (opcode+2)), location+1);
 653                                 signal = math_emu_stfpc(opcode, regs);
 654                         } else if (opcode[1] == 0x9d) {
 655                                 get_user(*((__u16 *) (opcode+2)), location+1);
 656                                 signal = math_emu_lfpc(opcode, regs);
 657                         } else
 658                                 signal = SIGILL;
 659                         break;
 660                 default:
 661                         signal = SIGILL;
 662                         break;
 663                 }
 664         }
 665 #endif
 666         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 667                 signal = SIGFPE;
 668         else
 669                 signal = SIGILL;
 670         if (signal == SIGFPE)
 671                 do_fp_trap(regs, location,
 672                            current->thread.fp_regs.fpc, interruption_code);
 673         else if (signal) {
 674                 siginfo_t info;
 675                 info.si_signo = signal;
 676                 info.si_errno = 0;
 677                 info.si_code = ILL_ILLOPN;
 678                 info.si_addr = location;
 679                 do_trap(interruption_code, signal,
 680                         "data exception", regs, &info);
 681         }
 682 }
 683
 684 static void space_switch_exception(struct pt_regs * regs, long int_code)
 685 {
 686         siginfo_t info;
 687
 688         /* Set user psw back to home space mode. */
 689         if (regs->psw.mask & PSW_MASK_PSTATE)
 690                 regs->psw.mask |= PSW_ASC_HOME;
 691         /* Send SIGILL. */
 692         info.si_signo = SIGILL;
 693         info.si_errno = 0;
 694         info.si_code = ILL_PRVOPC;
 695         info.si_addr = get_check_address(regs);
 696         do_trap(int_code, SIGILL, "space switch event", regs, &info);
 697 }
 698
 699 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 700 {
 701         bust_spinlocks(1);
 702         printk("Kernel stack overflow.\n");
 703         show_regs(regs);
 704         bust_spinlocks(0);
 705         panic("Corrupt kernel stack, can't continue.");
 706 }
 707
 708 /* init is done in lowcore.S and head.S */
 709
 710 void __init trap_init(void)
 711 {
 712         int i;
 713
 714         for (i = 0; i < 128; i++)
 715           pgm_check_table[i] = &default_trap_handler;
 716         pgm_check_table[1] = &illegal_op;
 717         pgm_check_table[2] = &privileged_op;
 718         pgm_check_table[3] = &execute_exception;
 719         pgm_check_table[4] = &do_protection_exception;
 720         pgm_check_table[5] = &addressing_exception;
 721         pgm_check_table[6] = &specification_exception;
 722         pgm_check_table[7] = &data_exception;
 723         pgm_check_table[8] = &overflow_exception;
 724         pgm_check_table[9] = &divide_exception;
 725         pgm_check_table[0x0A] = &overflow_exception;
 726         pgm_check_table[0x0B] = &divide_exception;
 727         pgm_check_table[0x0C] = &hfp_overflow_exception;
 728         pgm_check_table[0x0D] = &hfp_underflow_exception;
 729         pgm_check_table[0x0E] = &hfp_significance_exception;
 730         pgm_check_table[0x0F] = &hfp_divide_exception;
 731         pgm_check_table[0x10] = &do_dat_exception;
 732         pgm_check_table[0x11] = &do_dat_exception;
 733         pgm_check_table[0x12] = &translation_exception;
 734         pgm_check_table[0x13] = &special_op_exception;
 735 #ifdef CONFIG_64BIT
 736         pgm_check_table[0x38] = &do_dat_exception;
 737         pgm_check_table[0x39] = &do_dat_exception;
 738         pgm_check_table[0x3A] = &do_dat_exception;
 739         pgm_check_table[0x3B] = &do_dat_exception;
 740 #endif /* CONFIG_64BIT */
 741         pgm_check_table[0x15] = &operand_exception;
 742         pgm_check_table[0x1C] = &space_switch_exception;
 743         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 744         pgm_check_table[0x40] = &do_monitor_call;
 745         pfault_irq_init();
 746 }