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