SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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/delay.h>
  28 #include <linux/module.h>
  29 #include <linux/kdebug.h>
  30 #include <linux/kallsyms.h>
  31 #include <linux/reboot.h>
  32 #include <linux/kprobes.h>
  33 #include <linux/bug.h>
  34 #include <linux/utsname.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         printk("CPU: %d %s %s %.*s\n",
 173                task_thread_info(current)->cpu, print_tainted(),
 174                init_utsname()->release,
 175                (int)strcspn(init_utsname()->version, " "),
 176                init_utsname()->version);
 177         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 178                current->comm, current->pid, current,
 179                (void *) current->thread.ksp);
 180         show_stack(NULL, NULL);
 181 }
 182 EXPORT_SYMBOL(dump_stack);
 183
 184 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 185 {
 186         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 187 }
 188
 189 void show_registers(struct pt_regs *regs)
 190 {
 191         char *mode;
 192
 193         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 194         printk("%s PSW : %p %p",
 195                mode, (void *) regs->psw.mask,
 196                (void *) regs->psw.addr);
 197         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 198         printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 199                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 200                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 201                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 202                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 203                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 204                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 205 #ifdef CONFIG_64BIT
 206         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 207 #endif
 208         printk("\n%s GPRS: " FOURLONG, mode,
 209                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 210         printk("           " FOURLONG,
 211                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 212         printk("           " FOURLONG,
 213                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 214         printk("           " FOURLONG,
 215                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 216
 217         show_code(regs);
 218 }
 219
 220 /* This is called from fs/proc/array.c */
 221 char *task_show_regs(struct task_struct *task, char *buffer)
 222 {
 223         struct pt_regs *regs;
 224
 225         regs = task_pt_regs(task);
 226         buffer += sprintf(buffer, "task: %p, ksp: %p\n",
 227                        task, (void *)task->thread.ksp);
 228         buffer += sprintf(buffer, "User PSW : %p %p\n",
 229                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 230
 231         buffer += sprintf(buffer, "User GPRS: " FOURLONG,
 232                           regs->gprs[0], regs->gprs[1],
 233                           regs->gprs[2], regs->gprs[3]);
 234         buffer += sprintf(buffer, "           " FOURLONG,
 235                           regs->gprs[4], regs->gprs[5],
 236                           regs->gprs[6], regs->gprs[7]);
 237         buffer += sprintf(buffer, "           " FOURLONG,
 238                           regs->gprs[8], regs->gprs[9],
 239                           regs->gprs[10], regs->gprs[11]);
 240         buffer += sprintf(buffer, "           " FOURLONG,
 241                           regs->gprs[12], regs->gprs[13],
 242                           regs->gprs[14], regs->gprs[15]);
 243         buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
 244                           task->thread.acrs[0], task->thread.acrs[1],
 245                           task->thread.acrs[2], task->thread.acrs[3]);
 246         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 247                           task->thread.acrs[4], task->thread.acrs[5],
 248                           task->thread.acrs[6], task->thread.acrs[7]);
 249         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 250                           task->thread.acrs[8], task->thread.acrs[9],
 251                           task->thread.acrs[10], task->thread.acrs[11]);
 252         buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
 253                           task->thread.acrs[12], task->thread.acrs[13],
 254                           task->thread.acrs[14], task->thread.acrs[15]);
 255         return buffer;
 256 }
 257
 258 static DEFINE_SPINLOCK(die_lock);
 259
 260 void die(const char * str, struct pt_regs * regs, long err)
 261 {
 262         static int die_counter;
 263
 264         oops_enter();
 265         debug_stop_all();
 266         console_verbose();
 267         spin_lock_irq(&die_lock);
 268         bust_spinlocks(1);
 269         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 270 #ifdef CONFIG_PREEMPT
 271         printk("PREEMPT ");
 272 #endif
 273 #ifdef CONFIG_SMP
 274         printk("SMP ");
 275 #endif
 276 #ifdef CONFIG_DEBUG_PAGEALLOC
 277         printk("DEBUG_PAGEALLOC");
 278 #endif
 279         printk("\n");
 280         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
 281         show_regs(regs);
 282         bust_spinlocks(0);
 283         add_taint(TAINT_DIE);
 284         spin_unlock_irq(&die_lock);
 285         if (in_interrupt())
 286                 panic("Fatal exception in interrupt");
 287         if (panic_on_oops)
 288                 panic("Fatal exception: panic_on_oops");
 289         oops_exit();
 290         do_exit(SIGSEGV);
 291 }
 292
 293 static void inline
 294 report_user_fault(long interruption_code, struct pt_regs *regs)
 295 {
 296 #if defined(CONFIG_SYSCTL)
 297         if (!sysctl_userprocess_debug)
 298                 return;
 299 #endif
 300 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 301         printk("User process fault: interruption code 0x%lX\n",
 302                interruption_code);
 303         show_regs(regs);
 304 #endif
 305 }
 306
 307 int is_valid_bugaddr(unsigned long addr)
 308 {
 309         return 1;
 310 }
 311
 312 static void __kprobes inline do_trap(long interruption_code, int signr,
 313                                         char *str, struct pt_regs *regs,
 314                                         siginfo_t *info)
 315 {
 316         /*
 317          * We got all needed information from the lowcore and can
 318          * now safely switch on interrupts.
 319          */
 320         if (regs->psw.mask & PSW_MASK_PSTATE)
 321                 local_irq_enable();
 322
 323         if (notify_die(DIE_TRAP, str, regs, interruption_code,
 324                                 interruption_code, signr) == NOTIFY_STOP)
 325                 return;
 326
 327         if (regs->psw.mask & PSW_MASK_PSTATE) {
 328                 struct task_struct *tsk = current;
 329
 330                 tsk->thread.trap_no = interruption_code & 0xffff;
 331                 force_sig_info(signr, info, tsk);
 332                 report_user_fault(interruption_code, regs);
 333         } else {
 334                 const struct exception_table_entry *fixup;
 335                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 336                 if (fixup)
 337                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 338                 else {
 339                         enum bug_trap_type btt;
 340
 341                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 342                         if (btt == BUG_TRAP_TYPE_WARN)
 343                                 return;
 344                         die(str, regs, interruption_code);
 345                 }
 346         }
 347 }
 348
 349 static inline void __user *get_check_address(struct pt_regs *regs)
 350 {
 351         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 352 }
 353
 354 void __kprobes do_single_step(struct pt_regs *regs)
 355 {
 356         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 357                                         SIGTRAP) == NOTIFY_STOP){
 358                 return;
 359         }
 360         if ((current->ptrace & PT_PTRACED) != 0)
 361                 force_sig(SIGTRAP, current);
 362 }
 363
 364 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 365 {
 366         if (regs->psw.mask & PSW_MASK_PSTATE) {
 367                 local_irq_enable();
 368                 do_exit(SIGSEGV);
 369                 report_user_fault(interruption_code, regs);
 370         } else
 371                 die("Unknown program exception", regs, interruption_code);
 372 }
 373
 374 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 375 static void name(struct pt_regs * regs, long interruption_code) \
 376 { \
 377         siginfo_t info; \
 378         info.si_signo = signr; \
 379         info.si_errno = 0; \
 380         info.si_code = sicode; \
 381         info.si_addr = siaddr; \
 382         do_trap(interruption_code, signr, str, regs, &info); \
 383 }
 384
 385 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 386               ILL_ILLADR, get_check_address(regs))
 387 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 388               ILL_ILLOPN, get_check_address(regs))
 389 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 390               FPE_INTDIV, get_check_address(regs))
 391 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 392               FPE_INTOVF, get_check_address(regs))
 393 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 394               FPE_FLTOVF, get_check_address(regs))
 395 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 396               FPE_FLTUND, get_check_address(regs))
 397 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 398               FPE_FLTRES, get_check_address(regs))
 399 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 400               FPE_FLTDIV, get_check_address(regs))
 401 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 402               FPE_FLTINV, get_check_address(regs))
 403 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 404               ILL_ILLOPN, get_check_address(regs))
 405 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 406               ILL_PRVOPC, get_check_address(regs))
 407 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 408               ILL_ILLOPN, get_check_address(regs))
 409 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 410               ILL_ILLOPN, get_check_address(regs))
 411
 412 static inline void
 413 do_fp_trap(struct pt_regs *regs, void __user *location,
 414            int fpc, long interruption_code)
 415 {
 416         siginfo_t si;
 417
 418         si.si_signo = SIGFPE;
 419         si.si_errno = 0;
 420         si.si_addr = location;
 421         si.si_code = 0;
 422         /* FPC[2] is Data Exception Code */
 423         if ((fpc & 0x00000300) == 0) {
 424                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 425                 if (fpc & 0x8000) /* invalid fp operation */
 426                         si.si_code = FPE_FLTINV;
 427                 else if (fpc & 0x4000) /* div by 0 */
 428                         si.si_code = FPE_FLTDIV;
 429                 else if (fpc & 0x2000) /* overflow */
 430                         si.si_code = FPE_FLTOVF;
 431                 else if (fpc & 0x1000) /* underflow */
 432                         si.si_code = FPE_FLTUND;
 433                 else if (fpc & 0x0800) /* inexact */
 434                         si.si_code = FPE_FLTRES;
 435         }
 436         current->thread.ieee_instruction_pointer = (addr_t) location;
 437         do_trap(interruption_code, SIGFPE,
 438                 "floating point exception", regs, &si);
 439 }
 440
 441 static void illegal_op(struct pt_regs * regs, long interruption_code)
 442 {
 443         siginfo_t info;
 444         __u8 opcode[6];
 445         __u16 __user *location;
 446         int signal = 0;
 447
 448         location = get_check_address(regs);
 449
 450         /*
 451          * We got all needed information from the lowcore and can
 452          * now safely switch on interrupts.
 453          */
 454         if (regs->psw.mask & PSW_MASK_PSTATE)
 455                 local_irq_enable();
 456
 457         if (regs->psw.mask & PSW_MASK_PSTATE) {
 458                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 459                         return;
 460                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 461                         if (current->ptrace & PT_PTRACED)
 462                                 force_sig(SIGTRAP, current);
 463                         else
 464                                 signal = SIGILL;
 465 #ifdef CONFIG_MATHEMU
 466                 } else if (opcode[0] == 0xb3) {
 467                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 468                                 return;
 469                         signal = math_emu_b3(opcode, regs);
 470                 } else if (opcode[0] == 0xed) {
 471                         if (get_user(*((__u32 *) (opcode+2)),
 472                                      (__u32 __user *)(location+1)))
 473                                 return;
 474                         signal = math_emu_ed(opcode, regs);
 475                 } else if (*((__u16 *) opcode) == 0xb299) {
 476                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 477                                 return;
 478                         signal = math_emu_srnm(opcode, regs);
 479                 } else if (*((__u16 *) opcode) == 0xb29c) {
 480                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 481                                 return;
 482                         signal = math_emu_stfpc(opcode, regs);
 483                 } else if (*((__u16 *) opcode) == 0xb29d) {
 484                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 485                                 return;
 486                         signal = math_emu_lfpc(opcode, regs);
 487 #endif
 488                 } else
 489                         signal = SIGILL;
 490         } else {
 491                 /*
 492                  * If we get an illegal op in kernel mode, send it through the
 493                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 494                  */
 495                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 496                                3, SIGTRAP) != NOTIFY_STOP)
 497                         signal = SIGILL;
 498         }
 499
 500 #ifdef CONFIG_MATHEMU
 501         if (signal == SIGFPE)
 502                 do_fp_trap(regs, location,
 503                            current->thread.fp_regs.fpc, interruption_code);
 504         else if (signal == SIGSEGV) {
 505                 info.si_signo = signal;
 506                 info.si_errno = 0;
 507                 info.si_code = SEGV_MAPERR;
 508                 info.si_addr = (void __user *) location;
 509                 do_trap(interruption_code, signal,
 510                         "user address fault", regs, &info);
 511         } else
 512 #endif
 513         if (signal) {
 514                 info.si_signo = signal;
 515                 info.si_errno = 0;
 516                 info.si_code = ILL_ILLOPC;
 517                 info.si_addr = (void __user *) location;
 518                 do_trap(interruption_code, signal,
 519                         "illegal operation", regs, &info);
 520         }
 521 }
 522
 523
 524 #ifdef CONFIG_MATHEMU
 525 asmlinkage void
 526 specification_exception(struct pt_regs * regs, long interruption_code)
 527 {
 528         __u8 opcode[6];
 529         __u16 __user *location = NULL;
 530         int signal = 0;
 531
 532         location = (__u16 __user *) get_check_address(regs);
 533
 534         /*
 535          * We got all needed information from the lowcore and can
 536          * now safely switch on interrupts.
 537          */
 538         if (regs->psw.mask & PSW_MASK_PSTATE)
 539                 local_irq_enable();
 540
 541         if (regs->psw.mask & PSW_MASK_PSTATE) {
 542                 get_user(*((__u16 *) opcode), location);
 543                 switch (opcode[0]) {
 544                 case 0x28: /* LDR Rx,Ry   */
 545                         signal = math_emu_ldr(opcode);
 546                         break;
 547                 case 0x38: /* LER Rx,Ry   */
 548                         signal = math_emu_ler(opcode);
 549                         break;
 550                 case 0x60: /* STD R,D(X,B) */
 551                         get_user(*((__u16 *) (opcode+2)), location+1);
 552                         signal = math_emu_std(opcode, regs);
 553                         break;
 554                 case 0x68: /* LD R,D(X,B) */
 555                         get_user(*((__u16 *) (opcode+2)), location+1);
 556                         signal = math_emu_ld(opcode, regs);
 557                         break;
 558                 case 0x70: /* STE R,D(X,B) */
 559                         get_user(*((__u16 *) (opcode+2)), location+1);
 560                         signal = math_emu_ste(opcode, regs);
 561                         break;
 562                 case 0x78: /* LE R,D(X,B) */
 563                         get_user(*((__u16 *) (opcode+2)), location+1);
 564                         signal = math_emu_le(opcode, regs);
 565                         break;
 566                 default:
 567                         signal = SIGILL;
 568                         break;
 569                 }
 570         } else
 571                 signal = SIGILL;
 572
 573         if (signal == SIGFPE)
 574                 do_fp_trap(regs, location,
 575                            current->thread.fp_regs.fpc, interruption_code);
 576         else if (signal) {
 577                 siginfo_t info;
 578                 info.si_signo = signal;
 579                 info.si_errno = 0;
 580                 info.si_code = ILL_ILLOPN;
 581                 info.si_addr = location;
 582                 do_trap(interruption_code, signal,
 583                         "specification exception", regs, &info);
 584         }
 585 }
 586 #else
 587 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 588               ILL_ILLOPN, get_check_address(regs));
 589 #endif
 590
 591 static void data_exception(struct pt_regs * regs, long interruption_code)
 592 {
 593         __u16 __user *location;
 594         int signal = 0;
 595
 596         location = get_check_address(regs);
 597
 598         /*
 599          * We got all needed information from the lowcore and can
 600          * now safely switch on interrupts.
 601          */
 602         if (regs->psw.mask & PSW_MASK_PSTATE)
 603                 local_irq_enable();
 604
 605         if (MACHINE_HAS_IEEE)
 606                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 607
 608 #ifdef CONFIG_MATHEMU
 609         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 610                 __u8 opcode[6];
 611                 get_user(*((__u16 *) opcode), location);
 612                 switch (opcode[0]) {
 613                 case 0x28: /* LDR Rx,Ry   */
 614                         signal = math_emu_ldr(opcode);
 615                         break;
 616                 case 0x38: /* LER Rx,Ry   */
 617                         signal = math_emu_ler(opcode);
 618                         break;
 619                 case 0x60: /* STD R,D(X,B) */
 620                         get_user(*((__u16 *) (opcode+2)), location+1);
 621                         signal = math_emu_std(opcode, regs);
 622                         break;
 623                 case 0x68: /* LD R,D(X,B) */
 624                         get_user(*((__u16 *) (opcode+2)), location+1);
 625                         signal = math_emu_ld(opcode, regs);
 626                         break;
 627                 case 0x70: /* STE R,D(X,B) */
 628                         get_user(*((__u16 *) (opcode+2)), location+1);
 629                         signal = math_emu_ste(opcode, regs);
 630                         break;
 631                 case 0x78: /* LE R,D(X,B) */
 632                         get_user(*((__u16 *) (opcode+2)), location+1);
 633                         signal = math_emu_le(opcode, regs);
 634                         break;
 635                 case 0xb3:
 636                         get_user(*((__u16 *) (opcode+2)), location+1);
 637                         signal = math_emu_b3(opcode, regs);
 638                         break;
 639                 case 0xed:
 640                         get_user(*((__u32 *) (opcode+2)),
 641                                  (__u32 __user *)(location+1));
 642                         signal = math_emu_ed(opcode, regs);
 643                         break;
 644                 case 0xb2:
 645                         if (opcode[1] == 0x99) {
 646                                 get_user(*((__u16 *) (opcode+2)), location+1);
 647                                 signal = math_emu_srnm(opcode, regs);
 648                         } else if (opcode[1] == 0x9c) {
 649                                 get_user(*((__u16 *) (opcode+2)), location+1);
 650                                 signal = math_emu_stfpc(opcode, regs);
 651                         } else if (opcode[1] == 0x9d) {
 652                                 get_user(*((__u16 *) (opcode+2)), location+1);
 653                                 signal = math_emu_lfpc(opcode, regs);
 654                         } else
 655                                 signal = SIGILL;
 656                         break;
 657                 default:
 658                         signal = SIGILL;
 659                         break;
 660                 }
 661         }
 662 #endif
 663         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 664                 signal = SIGFPE;
 665         else
 666                 signal = SIGILL;
 667         if (signal == SIGFPE)
 668                 do_fp_trap(regs, location,
 669                            current->thread.fp_regs.fpc, interruption_code);
 670         else if (signal) {
 671                 siginfo_t info;
 672                 info.si_signo = signal;
 673                 info.si_errno = 0;
 674                 info.si_code = ILL_ILLOPN;
 675                 info.si_addr = location;
 676                 do_trap(interruption_code, signal,
 677                         "data exception", regs, &info);
 678         }
 679 }
 680
 681 static void space_switch_exception(struct pt_regs * regs, long int_code)
 682 {
 683         siginfo_t info;
 684
 685         /* Set user psw back to home space mode. */
 686         if (regs->psw.mask & PSW_MASK_PSTATE)
 687                 regs->psw.mask |= PSW_ASC_HOME;
 688         /* Send SIGILL. */
 689         info.si_signo = SIGILL;
 690         info.si_errno = 0;
 691         info.si_code = ILL_PRVOPC;
 692         info.si_addr = get_check_address(regs);
 693         do_trap(int_code, SIGILL, "space switch event", regs, &info);
 694 }
 695
 696 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 697 {
 698         bust_spinlocks(1);
 699         printk("Kernel stack overflow.\n");
 700         show_regs(regs);
 701         bust_spinlocks(0);
 702         panic("Corrupt kernel stack, can't continue.");
 703 }
 704
 705 /* init is done in lowcore.S and head.S */
 706
 707 void __init trap_init(void)
 708 {
 709         int i;
 710
 711         for (i = 0; i < 128; i++)
 712           pgm_check_table[i] = &default_trap_handler;
 713         pgm_check_table[1] = &illegal_op;
 714         pgm_check_table[2] = &privileged_op;
 715         pgm_check_table[3] = &execute_exception;
 716         pgm_check_table[4] = &do_protection_exception;
 717         pgm_check_table[5] = &addressing_exception;
 718         pgm_check_table[6] = &specification_exception;
 719         pgm_check_table[7] = &data_exception;
 720         pgm_check_table[8] = &overflow_exception;
 721         pgm_check_table[9] = &divide_exception;
 722         pgm_check_table[0x0A] = &overflow_exception;
 723         pgm_check_table[0x0B] = &divide_exception;
 724         pgm_check_table[0x0C] = &hfp_overflow_exception;
 725         pgm_check_table[0x0D] = &hfp_underflow_exception;
 726         pgm_check_table[0x0E] = &hfp_significance_exception;
 727         pgm_check_table[0x0F] = &hfp_divide_exception;
 728         pgm_check_table[0x10] = &do_dat_exception;
 729         pgm_check_table[0x11] = &do_dat_exception;
 730         pgm_check_table[0x12] = &translation_exception;
 731         pgm_check_table[0x13] = &special_op_exception;
 732 #ifdef CONFIG_64BIT
 733         pgm_check_table[0x38] = &do_dat_exception;
 734         pgm_check_table[0x39] = &do_dat_exception;
 735         pgm_check_table[0x3A] = &do_dat_exception;
 736         pgm_check_table[0x3B] = &do_dat_exception;
 737 #endif /* CONFIG_64BIT */
 738         pgm_check_table[0x15] = &operand_exception;
 739         pgm_check_table[0x1C] = &space_switch_exception;
 740         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 741         pgm_check_table[0x40] = &do_monitor_call;
 742         pfault_irq_init();
 743 }