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/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/delay.h>
  29 #include <linux/module.h>
  30 #include <linux/kdebug.h>
  31 #include <linux/kallsyms.h>
  32 #include <linux/reboot.h>
  33 #include <linux/kprobes.h>
  34 #include <linux/bug.h>
  35 #include <linux/utsname.h>
  36 #include <asm/system.h>
  37 #include <asm/uaccess.h>
  38 #include <asm/io.h>
  39 #include <asm/atomic.h>
  40 #include <asm/mathemu.h>
  41 #include <asm/cpcmd.h>
  42 #include <asm/s390_ext.h>
  43 #include <asm/lowcore.h>
  44 #include <asm/debug.h>
  45
  46 /* Called from entry.S only */
  47 extern void handle_per_exception(struct pt_regs *regs);
  48
  49 typedef void pgm_check_handler_t(struct pt_regs *, long);
  50 pgm_check_handler_t *pgm_check_table[128];
  51
  52 #ifdef CONFIG_SYSCTL
  53 #ifdef CONFIG_PROCESS_DEBUG
  54 int sysctl_userprocess_debug = 1;
  55 #else
  56 int sysctl_userprocess_debug = 0;
  57 #endif
  58 #endif
  59
  60 extern pgm_check_handler_t do_protection_exception;
  61 extern pgm_check_handler_t do_dat_exception;
  62 extern pgm_check_handler_t do_monitor_call;
  63 extern pgm_check_handler_t do_asce_exception;
  64
  65 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
  66
  67 #ifndef CONFIG_64BIT
  68 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
  69 static int kstack_depth_to_print = 12;
  70 #else /* CONFIG_64BIT */
  71 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  72 static int kstack_depth_to_print = 20;
  73 #endif /* CONFIG_64BIT */
  74
  75 /*
  76  * For show_trace we have tree different stack to consider:
  77  *   - the panic stack which is used if the kernel stack has overflown
  78  *   - the asynchronous interrupt stack (cpu related)
  79  *   - the synchronous kernel stack (process related)
  80  * The stack trace can start at any of the three stack and can potentially
  81  * touch all of them. The order is: panic stack, async stack, sync stack.
  82  */
  83 static unsigned long
  84 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  85 {
  86         struct stack_frame *sf;
  87         struct pt_regs *regs;
  88
  89         while (1) {
  90                 sp = sp & PSW_ADDR_INSN;
  91                 if (sp < low || sp > high - sizeof(*sf))
  92                         return sp;
  93                 sf = (struct stack_frame *) sp;
  94                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  95                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
  96                 /* Follow the backchain. */
  97                 while (1) {
  98                         low = sp;
  99                         sp = sf->back_chain & PSW_ADDR_INSN;
 100                         if (!sp)
 101                                 break;
 102                         if (sp <= low || sp > high - sizeof(*sf))
 103                                 return sp;
 104                         sf = (struct stack_frame *) sp;
 105                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 106                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 107                 }
 108                 /* Zero backchain detected, check for interrupt frame. */
 109                 sp = (unsigned long) (sf + 1);
 110                 if (sp <= low || sp > high - sizeof(*regs))
 111                         return sp;
 112                 regs = (struct pt_regs *) sp;
 113                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 114                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 115                 low = sp;
 116                 sp = regs->gprs[15];
 117         }
 118 }
 119
 120 void show_trace(struct task_struct *task, unsigned long *stack)
 121 {
 122         register unsigned long __r15 asm ("15");
 123         unsigned long sp;
 124
 125         sp = (unsigned long) stack;
 126         if (!sp)
 127                 sp = task ? task->thread.ksp : __r15;
 128         printk("Call Trace:\n");
 129 #ifdef CONFIG_CHECK_STACK
 130         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 131                           S390_lowcore.panic_stack);
 132 #endif
 133         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 134                           S390_lowcore.async_stack);
 135         if (task)
 136                 __show_trace(sp, (unsigned long) task_stack_page(task),
 137                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
 138         else
 139                 __show_trace(sp, S390_lowcore.thread_info,
 140                              S390_lowcore.thread_info + THREAD_SIZE);
 141         printk("\n");
 142         if (!task)
 143                 task = current;
 144         debug_show_held_locks(task);
 145 }
 146
 147 void show_stack(struct task_struct *task, unsigned long *sp)
 148 {
 149         register unsigned long * __r15 asm ("15");
 150         unsigned long *stack;
 151         int i;
 152
 153         if (!sp)
 154                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
 155         else
 156                 stack = sp;
 157
 158         for (i = 0; i < kstack_depth_to_print; i++) {
 159                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 160                         break;
 161                 if (i && ((i * sizeof (long) % 32) == 0))
 162                         printk("\n       ");
 163                 printk("%p ", (void *)*stack++);
 164         }
 165         printk("\n");
 166         show_trace(task, sp);
 167 }
 168
 169 /*
 170  * The architecture-independent dump_stack generator
 171  */
 172 void dump_stack(void)
 173 {
 174         printk("CPU: %d %s %s %.*s\n",
 175                task_thread_info(current)->cpu, print_tainted(),
 176                init_utsname()->release,
 177                (int)strcspn(init_utsname()->version, " "),
 178                init_utsname()->version);
 179         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 180                current->comm, current->pid, current,
 181                (void *) current->thread.ksp);
 182         show_stack(NULL, NULL);
 183 }
 184 EXPORT_SYMBOL(dump_stack);
 185
 186 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 187 {
 188         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 189 }
 190
 191 void show_registers(struct pt_regs *regs)
 192 {
 193         char *mode;
 194
 195         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 196         printk("%s PSW : %p %p",
 197                mode, (void *) regs->psw.mask,
 198                (void *) regs->psw.addr);
 199         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 200         printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 201                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 202                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 203                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 204                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 205                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 206                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 207 #ifdef CONFIG_64BIT
 208         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 209 #endif
 210         printk("\n%s GPRS: " FOURLONG, mode,
 211                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 212         printk("           " FOURLONG,
 213                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 214         printk("           " FOURLONG,
 215                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 216         printk("           " FOURLONG,
 217                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 218
 219         show_code(regs);
 220 }
 221
 222 /* This is called from fs/proc/array.c */
 223 void task_show_regs(struct seq_file *m, struct task_struct *task)
 224 {
 225         struct pt_regs *regs;
 226
 227         regs = task_pt_regs(task);
 228         seq_printf(m, "task: %p, ksp: %p\n",
 229                        task, (void *)task->thread.ksp);
 230         seq_printf(m, "User PSW : %p %p\n",
 231                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 232
 233         seq_printf(m, "User GPRS: " FOURLONG,
 234                           regs->gprs[0], regs->gprs[1],
 235                           regs->gprs[2], regs->gprs[3]);
 236         seq_printf(m, "           " FOURLONG,
 237                           regs->gprs[4], regs->gprs[5],
 238                           regs->gprs[6], regs->gprs[7]);
 239         seq_printf(m, "           " FOURLONG,
 240                           regs->gprs[8], regs->gprs[9],
 241                           regs->gprs[10], regs->gprs[11]);
 242         seq_printf(m, "           " FOURLONG,
 243                           regs->gprs[12], regs->gprs[13],
 244                           regs->gprs[14], regs->gprs[15]);
 245         seq_printf(m, "User ACRS: %08x %08x %08x %08x\n",
 246                           task->thread.acrs[0], task->thread.acrs[1],
 247                           task->thread.acrs[2], task->thread.acrs[3]);
 248         seq_printf(m, "           %08x %08x %08x %08x\n",
 249                           task->thread.acrs[4], task->thread.acrs[5],
 250                           task->thread.acrs[6], task->thread.acrs[7]);
 251         seq_printf(m, "           %08x %08x %08x %08x\n",
 252                           task->thread.acrs[8], task->thread.acrs[9],
 253                           task->thread.acrs[10], task->thread.acrs[11]);
 254         seq_printf(m, "           %08x %08x %08x %08x\n",
 255                           task->thread.acrs[12], task->thread.acrs[13],
 256                           task->thread.acrs[14], task->thread.acrs[15]);
 257 }
 258
 259 static DEFINE_SPINLOCK(die_lock);
 260
 261 void die(const char * str, struct pt_regs * regs, long err)
 262 {
 263         static int die_counter;
 264
 265         oops_enter();
 266         debug_stop_all();
 267         console_verbose();
 268         spin_lock_irq(&die_lock);
 269         bust_spinlocks(1);
 270         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 271 #ifdef CONFIG_PREEMPT
 272         printk("PREEMPT ");
 273 #endif
 274 #ifdef CONFIG_SMP
 275         printk("SMP ");
 276 #endif
 277 #ifdef CONFIG_DEBUG_PAGEALLOC
 278         printk("DEBUG_PAGEALLOC");
 279 #endif
 280         printk("\n");
 281         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
 282         show_regs(regs);
 283         bust_spinlocks(0);
 284         add_taint(TAINT_DIE);
 285         spin_unlock_irq(&die_lock);
 286         if (in_interrupt())
 287                 panic("Fatal exception in interrupt");
 288         if (panic_on_oops)
 289                 panic("Fatal exception: panic_on_oops");
 290         oops_exit();
 291         do_exit(SIGSEGV);
 292 }
 293
 294 static void inline
 295 report_user_fault(long interruption_code, struct pt_regs *regs)
 296 {
 297 #if defined(CONFIG_SYSCTL)
 298         if (!sysctl_userprocess_debug)
 299                 return;
 300 #endif
 301 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 302         printk("User process fault: interruption code 0x%lX\n",
 303                interruption_code);
 304         show_regs(regs);
 305 #endif
 306 }
 307
 308 int is_valid_bugaddr(unsigned long addr)
 309 {
 310         return 1;
 311 }
 312
 313 static void __kprobes inline do_trap(long interruption_code, int signr,
 314                                         char *str, struct pt_regs *regs,
 315                                         siginfo_t *info)
 316 {
 317         /*
 318          * We got all needed information from the lowcore and can
 319          * now safely switch on interrupts.
 320          */
 321         if (regs->psw.mask & PSW_MASK_PSTATE)
 322                 local_irq_enable();
 323
 324         if (notify_die(DIE_TRAP, str, regs, interruption_code,
 325                                 interruption_code, signr) == NOTIFY_STOP)
 326                 return;
 327
 328         if (regs->psw.mask & PSW_MASK_PSTATE) {
 329                 struct task_struct *tsk = current;
 330
 331                 tsk->thread.trap_no = interruption_code & 0xffff;
 332                 force_sig_info(signr, info, tsk);
 333                 report_user_fault(interruption_code, regs);
 334         } else {
 335                 const struct exception_table_entry *fixup;
 336                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 337                 if (fixup)
 338                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 339                 else {
 340                         enum bug_trap_type btt;
 341
 342                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 343                         if (btt == BUG_TRAP_TYPE_WARN)
 344                                 return;
 345                         die(str, regs, interruption_code);
 346                 }
 347         }
 348 }
 349
 350 static inline void __user *get_check_address(struct pt_regs *regs)
 351 {
 352         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 353 }
 354
 355 void __kprobes do_single_step(struct pt_regs *regs)
 356 {
 357         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 358                                         SIGTRAP) == NOTIFY_STOP){
 359                 return;
 360         }
 361         if ((current->ptrace & PT_PTRACED) != 0)
 362                 force_sig(SIGTRAP, current);
 363 }
 364
 365 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 366 {
 367         if (regs->psw.mask & PSW_MASK_PSTATE) {
 368                 local_irq_enable();
 369                 do_exit(SIGSEGV);
 370                 report_user_fault(interruption_code, regs);
 371         } else
 372                 die("Unknown program exception", regs, interruption_code);
 373 }
 374
 375 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 376 static void name(struct pt_regs * regs, long interruption_code) \
 377 { \
 378         siginfo_t info; \
 379         info.si_signo = signr; \
 380         info.si_errno = 0; \
 381         info.si_code = sicode; \
 382         info.si_addr = siaddr; \
 383         do_trap(interruption_code, signr, str, regs, &info); \
 384 }
 385
 386 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 387               ILL_ILLADR, get_check_address(regs))
 388 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 389               ILL_ILLOPN, get_check_address(regs))
 390 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 391               FPE_INTDIV, get_check_address(regs))
 392 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 393               FPE_INTOVF, get_check_address(regs))
 394 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 395               FPE_FLTOVF, get_check_address(regs))
 396 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 397               FPE_FLTUND, get_check_address(regs))
 398 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 399               FPE_FLTRES, get_check_address(regs))
 400 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 401               FPE_FLTDIV, get_check_address(regs))
 402 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 403               FPE_FLTINV, get_check_address(regs))
 404 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 405               ILL_ILLOPN, get_check_address(regs))
 406 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 407               ILL_PRVOPC, get_check_address(regs))
 408 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 409               ILL_ILLOPN, get_check_address(regs))
 410 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 411               ILL_ILLOPN, get_check_address(regs))
 412
 413 static inline void
 414 do_fp_trap(struct pt_regs *regs, void __user *location,
 415            int fpc, long interruption_code)
 416 {
 417         siginfo_t si;
 418
 419         si.si_signo = SIGFPE;
 420         si.si_errno = 0;
 421         si.si_addr = location;
 422         si.si_code = 0;
 423         /* FPC[2] is Data Exception Code */
 424         if ((fpc & 0x00000300) == 0) {
 425                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 426                 if (fpc & 0x8000) /* invalid fp operation */
 427                         si.si_code = FPE_FLTINV;
 428                 else if (fpc & 0x4000) /* div by 0 */
 429                         si.si_code = FPE_FLTDIV;
 430                 else if (fpc & 0x2000) /* overflow */
 431                         si.si_code = FPE_FLTOVF;
 432                 else if (fpc & 0x1000) /* underflow */
 433                         si.si_code = FPE_FLTUND;
 434                 else if (fpc & 0x0800) /* inexact */
 435                         si.si_code = FPE_FLTRES;
 436         }
 437         current->thread.ieee_instruction_pointer = (addr_t) location;
 438         do_trap(interruption_code, SIGFPE,
 439                 "floating point exception", regs, &si);
 440 }
 441
 442 static void illegal_op(struct pt_regs * regs, long interruption_code)
 443 {
 444         siginfo_t info;
 445         __u8 opcode[6];
 446         __u16 __user *location;
 447         int signal = 0;
 448
 449         location = get_check_address(regs);
 450
 451         /*
 452          * We got all needed information from the lowcore and can
 453          * now safely switch on interrupts.
 454          */
 455         if (regs->psw.mask & PSW_MASK_PSTATE)
 456                 local_irq_enable();
 457
 458         if (regs->psw.mask & PSW_MASK_PSTATE) {
 459                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 460                         return;
 461                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 462                         if (current->ptrace & PT_PTRACED)
 463                                 force_sig(SIGTRAP, current);
 464                         else
 465                                 signal = SIGILL;
 466 #ifdef CONFIG_MATHEMU
 467                 } else if (opcode[0] == 0xb3) {
 468                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 469                                 return;
 470                         signal = math_emu_b3(opcode, regs);
 471                 } else if (opcode[0] == 0xed) {
 472                         if (get_user(*((__u32 *) (opcode+2)),
 473                                      (__u32 __user *)(location+1)))
 474                                 return;
 475                         signal = math_emu_ed(opcode, regs);
 476                 } else if (*((__u16 *) opcode) == 0xb299) {
 477                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 478                                 return;
 479                         signal = math_emu_srnm(opcode, regs);
 480                 } else if (*((__u16 *) opcode) == 0xb29c) {
 481                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 482                                 return;
 483                         signal = math_emu_stfpc(opcode, regs);
 484                 } else if (*((__u16 *) opcode) == 0xb29d) {
 485                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 486                                 return;
 487                         signal = math_emu_lfpc(opcode, regs);
 488 #endif
 489                 } else
 490                         signal = SIGILL;
 491         } else {
 492                 /*
 493                  * If we get an illegal op in kernel mode, send it through the
 494                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 495                  */
 496                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 497                                3, SIGTRAP) != NOTIFY_STOP)
 498                         signal = SIGILL;
 499         }
 500
 501 #ifdef CONFIG_MATHEMU
 502         if (signal == SIGFPE)
 503                 do_fp_trap(regs, location,
 504                            current->thread.fp_regs.fpc, interruption_code);
 505         else if (signal == SIGSEGV) {
 506                 info.si_signo = signal;
 507                 info.si_errno = 0;
 508                 info.si_code = SEGV_MAPERR;
 509                 info.si_addr = (void __user *) location;
 510                 do_trap(interruption_code, signal,
 511                         "user address fault", regs, &info);
 512         } else
 513 #endif
 514         if (signal) {
 515                 info.si_signo = signal;
 516                 info.si_errno = 0;
 517                 info.si_code = ILL_ILLOPC;
 518                 info.si_addr = (void __user *) location;
 519                 do_trap(interruption_code, signal,
 520                         "illegal operation", regs, &info);
 521         }
 522 }
 523
 524
 525 #ifdef CONFIG_MATHEMU
 526 asmlinkage void
 527 specification_exception(struct pt_regs * regs, long interruption_code)
 528 {
 529         __u8 opcode[6];
 530         __u16 __user *location = NULL;
 531         int signal = 0;
 532
 533         location = (__u16 __user *) get_check_address(regs);
 534
 535         /*
 536          * We got all needed information from the lowcore and can
 537          * now safely switch on interrupts.
 538          */
 539         if (regs->psw.mask & PSW_MASK_PSTATE)
 540                 local_irq_enable();
 541
 542         if (regs->psw.mask & PSW_MASK_PSTATE) {
 543                 get_user(*((__u16 *) opcode), location);
 544                 switch (opcode[0]) {
 545                 case 0x28: /* LDR Rx,Ry   */
 546                         signal = math_emu_ldr(opcode);
 547                         break;
 548                 case 0x38: /* LER Rx,Ry   */
 549                         signal = math_emu_ler(opcode);
 550                         break;
 551                 case 0x60: /* STD R,D(X,B) */
 552                         get_user(*((__u16 *) (opcode+2)), location+1);
 553                         signal = math_emu_std(opcode, regs);
 554                         break;
 555                 case 0x68: /* LD R,D(X,B) */
 556                         get_user(*((__u16 *) (opcode+2)), location+1);
 557                         signal = math_emu_ld(opcode, regs);
 558                         break;
 559                 case 0x70: /* STE R,D(X,B) */
 560                         get_user(*((__u16 *) (opcode+2)), location+1);
 561                         signal = math_emu_ste(opcode, regs);
 562                         break;
 563                 case 0x78: /* LE R,D(X,B) */
 564                         get_user(*((__u16 *) (opcode+2)), location+1);
 565                         signal = math_emu_le(opcode, regs);
 566                         break;
 567                 default:
 568                         signal = SIGILL;
 569                         break;
 570                 }
 571         } else
 572                 signal = SIGILL;
 573
 574         if (signal == SIGFPE)
 575                 do_fp_trap(regs, location,
 576                            current->thread.fp_regs.fpc, interruption_code);
 577         else if (signal) {
 578                 siginfo_t info;
 579                 info.si_signo = signal;
 580                 info.si_errno = 0;
 581                 info.si_code = ILL_ILLOPN;
 582                 info.si_addr = location;
 583                 do_trap(interruption_code, signal,
 584                         "specification exception", regs, &info);
 585         }
 586 }
 587 #else
 588 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 589               ILL_ILLOPN, get_check_address(regs));
 590 #endif
 591
 592 static void data_exception(struct pt_regs * regs, long interruption_code)
 593 {
 594         __u16 __user *location;
 595         int signal = 0;
 596
 597         location = get_check_address(regs);
 598
 599         /*
 600          * We got all needed information from the lowcore and can
 601          * now safely switch on interrupts.
 602          */
 603         if (regs->psw.mask & PSW_MASK_PSTATE)
 604                 local_irq_enable();
 605
 606         if (MACHINE_HAS_IEEE)
 607                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 608
 609 #ifdef CONFIG_MATHEMU
 610         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 611                 __u8 opcode[6];
 612                 get_user(*((__u16 *) opcode), location);
 613                 switch (opcode[0]) {
 614                 case 0x28: /* LDR Rx,Ry   */
 615                         signal = math_emu_ldr(opcode);
 616                         break;
 617                 case 0x38: /* LER Rx,Ry   */
 618                         signal = math_emu_ler(opcode);
 619                         break;
 620                 case 0x60: /* STD R,D(X,B) */
 621                         get_user(*((__u16 *) (opcode+2)), location+1);
 622                         signal = math_emu_std(opcode, regs);
 623                         break;
 624                 case 0x68: /* LD R,D(X,B) */
 625                         get_user(*((__u16 *) (opcode+2)), location+1);
 626                         signal = math_emu_ld(opcode, regs);
 627                         break;
 628                 case 0x70: /* STE R,D(X,B) */
 629                         get_user(*((__u16 *) (opcode+2)), location+1);
 630                         signal = math_emu_ste(opcode, regs);
 631                         break;
 632                 case 0x78: /* LE R,D(X,B) */
 633                         get_user(*((__u16 *) (opcode+2)), location+1);
 634                         signal = math_emu_le(opcode, regs);
 635                         break;
 636                 case 0xb3:
 637                         get_user(*((__u16 *) (opcode+2)), location+1);
 638                         signal = math_emu_b3(opcode, regs);
 639                         break;
 640                 case 0xed:
 641                         get_user(*((__u32 *) (opcode+2)),
 642                                  (__u32 __user *)(location+1));
 643                         signal = math_emu_ed(opcode, regs);
 644                         break;
 645                 case 0xb2:
 646                         if (opcode[1] == 0x99) {
 647                                 get_user(*((__u16 *) (opcode+2)), location+1);
 648                                 signal = math_emu_srnm(opcode, regs);
 649                         } else if (opcode[1] == 0x9c) {
 650                                 get_user(*((__u16 *) (opcode+2)), location+1);
 651                                 signal = math_emu_stfpc(opcode, regs);
 652                         } else if (opcode[1] == 0x9d) {
 653                                 get_user(*((__u16 *) (opcode+2)), location+1);
 654                                 signal = math_emu_lfpc(opcode, regs);
 655                         } else
 656                                 signal = SIGILL;
 657                         break;
 658                 default:
 659                         signal = SIGILL;
 660                         break;
 661                 }
 662         }
 663 #endif
 664         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 665                 signal = SIGFPE;
 666         else
 667                 signal = SIGILL;
 668         if (signal == SIGFPE)
 669                 do_fp_trap(regs, location,
 670                            current->thread.fp_regs.fpc, interruption_code);
 671         else if (signal) {
 672                 siginfo_t info;
 673                 info.si_signo = signal;
 674                 info.si_errno = 0;
 675                 info.si_code = ILL_ILLOPN;
 676                 info.si_addr = location;
 677                 do_trap(interruption_code, signal,
 678                         "data exception", regs, &info);
 679         }
 680 }
 681
 682 static void space_switch_exception(struct pt_regs * regs, long int_code)
 683 {
 684         siginfo_t info;
 685
 686         /* Set user psw back to home space mode. */
 687         if (regs->psw.mask & PSW_MASK_PSTATE)
 688                 regs->psw.mask |= PSW_ASC_HOME;
 689         /* Send SIGILL. */
 690         info.si_signo = SIGILL;
 691         info.si_errno = 0;
 692         info.si_code = ILL_PRVOPC;
 693         info.si_addr = get_check_address(regs);
 694         do_trap(int_code, SIGILL, "space switch event", regs, &info);
 695 }
 696
 697 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 698 {
 699         bust_spinlocks(1);
 700         printk("Kernel stack overflow.\n");
 701         show_regs(regs);
 702         bust_spinlocks(0);
 703         panic("Corrupt kernel stack, can't continue.");
 704 }
 705
 706 /* init is done in lowcore.S and head.S */
 707
 708 void __init trap_init(void)
 709 {
 710         int i;
 711
 712         for (i = 0; i < 128; i++)
 713           pgm_check_table[i] = &default_trap_handler;
 714         pgm_check_table[1] = &illegal_op;
 715         pgm_check_table[2] = &privileged_op;
 716         pgm_check_table[3] = &execute_exception;
 717         pgm_check_table[4] = &do_protection_exception;
 718         pgm_check_table[5] = &addressing_exception;
 719         pgm_check_table[6] = &specification_exception;
 720         pgm_check_table[7] = &data_exception;
 721         pgm_check_table[8] = &overflow_exception;
 722         pgm_check_table[9] = &divide_exception;
 723         pgm_check_table[0x0A] = &overflow_exception;
 724         pgm_check_table[0x0B] = &divide_exception;
 725         pgm_check_table[0x0C] = &hfp_overflow_exception;
 726         pgm_check_table[0x0D] = &hfp_underflow_exception;
 727         pgm_check_table[0x0E] = &hfp_significance_exception;
 728         pgm_check_table[0x0F] = &hfp_divide_exception;
 729         pgm_check_table[0x10] = &do_dat_exception;
 730         pgm_check_table[0x11] = &do_dat_exception;
 731         pgm_check_table[0x12] = &translation_exception;
 732         pgm_check_table[0x13] = &special_op_exception;
 733 #ifdef CONFIG_64BIT
 734         pgm_check_table[0x38] = &do_asce_exception;
 735         pgm_check_table[0x39] = &do_dat_exception;
 736         pgm_check_table[0x3A] = &do_dat_exception;
 737         pgm_check_table[0x3B] = &do_dat_exception;
 738 #endif /* CONFIG_64BIT */
 739         pgm_check_table[0x15] = &operand_exception;
 740         pgm_check_table[0x1C] = &space_switch_exception;
 741         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 742         pgm_check_table[0x40] = &do_monitor_call;
 743         pfault_irq_init();
 744 }