linux/arch/s390/kernel/traps.c
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   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#include "entry.h"
  46
  47pgm_check_handler_t *pgm_check_table[128];
  48
  49#ifdef CONFIG_SYSCTL
  50#ifdef CONFIG_PROCESS_DEBUG
  51int sysctl_userprocess_debug = 1;
  52#else
  53int sysctl_userprocess_debug = 0;
  54#endif
  55#endif
  56
  57extern pgm_check_handler_t do_protection_exception;
  58extern pgm_check_handler_t do_dat_exception;
  59extern pgm_check_handler_t do_asce_exception;
  60
  61#define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
  62
  63#ifndef CONFIG_64BIT
  64#define LONG "%08lx "
  65#define FOURLONG "%08lx %08lx %08lx %08lx\n"
  66static int kstack_depth_to_print = 12;
  67#else /* CONFIG_64BIT */
  68#define LONG "%016lx "
  69#define FOURLONG "%016lx %016lx %016lx %016lx\n"
  70static 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 */
  81static 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
 118static 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        if (!task)
 140                task = current;
 141        debug_show_held_locks(task);
 142}
 143
 144void show_stack(struct task_struct *task, unsigned long *sp)
 145{
 146        register unsigned long * __r15 asm ("15");
 147        unsigned long *stack;
 148        int i;
 149
 150        if (!sp)
 151                stack = task ? (unsigned long *) task->thread.ksp : __r15;
 152        else
 153                stack = sp;
 154
 155        for (i = 0; i < kstack_depth_to_print; i++) {
 156                if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 157                        break;
 158                if (i && ((i * sizeof (long) % 32) == 0))
 159                        printk("\n       ");
 160                printk(LONG, *stack++);
 161        }
 162        printk("\n");
 163        show_trace(task, sp);
 164}
 165
 166static void show_last_breaking_event(struct pt_regs *regs)
 167{
 168#ifdef CONFIG_64BIT
 169        printk("Last Breaking-Event-Address:\n");
 170        printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
 171        print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
 172#endif
 173}
 174
 175/*
 176 * The architecture-independent dump_stack generator
 177 */
 178void dump_stack(void)
 179{
 180        printk("CPU: %d %s %s %.*s\n",
 181               task_thread_info(current)->cpu, print_tainted(),
 182               init_utsname()->release,
 183               (int)strcspn(init_utsname()->version, " "),
 184               init_utsname()->version);
 185        printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 186               current->comm, current->pid, current,
 187               (void *) current->thread.ksp);
 188        show_stack(NULL, NULL);
 189}
 190EXPORT_SYMBOL(dump_stack);
 191
 192static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 193{
 194        return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 195}
 196
 197void show_registers(struct pt_regs *regs)
 198{
 199        char *mode;
 200
 201        mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 202        printk("%s PSW : %p %p",
 203               mode, (void *) regs->psw.mask,
 204               (void *) regs->psw.addr);
 205        print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 206        printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 207               "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 208               mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 209               mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 210               mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 211               mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 212               mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 213#ifdef CONFIG_64BIT
 214        printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 215#endif
 216        printk("\n%s GPRS: " FOURLONG, mode,
 217               regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 218        printk("           " FOURLONG,
 219               regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 220        printk("           " FOURLONG,
 221               regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 222        printk("           " FOURLONG,
 223               regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 224
 225        show_code(regs);
 226}       
 227
 228void show_regs(struct pt_regs *regs)
 229{
 230        print_modules();
 231        printk("CPU: %d %s %s %.*s\n",
 232               task_thread_info(current)->cpu, print_tainted(),
 233               init_utsname()->release,
 234               (int)strcspn(init_utsname()->version, " "),
 235               init_utsname()->version);
 236        printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 237               current->comm, current->pid, current,
 238               (void *) current->thread.ksp);
 239        show_registers(regs);
 240        /* Show stack backtrace if pt_regs is from kernel mode */
 241        if (!(regs->psw.mask & PSW_MASK_PSTATE))
 242                show_trace(NULL, (unsigned long *) regs->gprs[15]);
 243        show_last_breaking_event(regs);
 244}
 245
 246/* This is called from fs/proc/array.c */
 247void task_show_regs(struct seq_file *m, struct task_struct *task)
 248{
 249        struct pt_regs *regs;
 250
 251        regs = task_pt_regs(task);
 252        seq_printf(m, "task: %p, ksp: %p\n",
 253                       task, (void *)task->thread.ksp);
 254        seq_printf(m, "User PSW : %p %p\n",
 255                       (void *) regs->psw.mask, (void *)regs->psw.addr);
 256
 257        seq_printf(m, "User GPRS: " FOURLONG,
 258                          regs->gprs[0], regs->gprs[1],
 259                          regs->gprs[2], regs->gprs[3]);
 260        seq_printf(m, "           " FOURLONG,
 261                          regs->gprs[4], regs->gprs[5],
 262                          regs->gprs[6], regs->gprs[7]);
 263        seq_printf(m, "           " FOURLONG,
 264                          regs->gprs[8], regs->gprs[9],
 265                          regs->gprs[10], regs->gprs[11]);
 266        seq_printf(m, "           " FOURLONG,
 267                          regs->gprs[12], regs->gprs[13],
 268                          regs->gprs[14], regs->gprs[15]);
 269        seq_printf(m, "User ACRS: %08x %08x %08x %08x\n",
 270                          task->thread.acrs[0], task->thread.acrs[1],
 271                          task->thread.acrs[2], task->thread.acrs[3]);
 272        seq_printf(m, "           %08x %08x %08x %08x\n",
 273                          task->thread.acrs[4], task->thread.acrs[5],
 274                          task->thread.acrs[6], task->thread.acrs[7]);
 275        seq_printf(m, "           %08x %08x %08x %08x\n",
 276                          task->thread.acrs[8], task->thread.acrs[9],
 277                          task->thread.acrs[10], task->thread.acrs[11]);
 278        seq_printf(m, "           %08x %08x %08x %08x\n",
 279                          task->thread.acrs[12], task->thread.acrs[13],
 280                          task->thread.acrs[14], task->thread.acrs[15]);
 281}
 282
 283static DEFINE_SPINLOCK(die_lock);
 284
 285void die(const char * str, struct pt_regs * regs, long err)
 286{
 287        static int die_counter;
 288
 289        oops_enter();
 290        debug_stop_all();
 291        console_verbose();
 292        spin_lock_irq(&die_lock);
 293        bust_spinlocks(1);
 294        printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 295#ifdef CONFIG_PREEMPT
 296        printk("PREEMPT ");
 297#endif
 298#ifdef CONFIG_SMP
 299        printk("SMP ");
 300#endif
 301#ifdef CONFIG_DEBUG_PAGEALLOC
 302        printk("DEBUG_PAGEALLOC");
 303#endif
 304        printk("\n");
 305        notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
 306        show_regs(regs);
 307        bust_spinlocks(0);
 308        add_taint(TAINT_DIE);
 309        spin_unlock_irq(&die_lock);
 310        if (in_interrupt())
 311                panic("Fatal exception in interrupt");
 312        if (panic_on_oops)
 313                panic("Fatal exception: panic_on_oops");
 314        oops_exit();
 315        do_exit(SIGSEGV);
 316}
 317
 318static void inline
 319report_user_fault(long interruption_code, struct pt_regs *regs)
 320{
 321#if defined(CONFIG_SYSCTL)
 322        if (!sysctl_userprocess_debug)
 323                return;
 324#endif
 325#if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 326        printk("User process fault: interruption code 0x%lX\n",
 327               interruption_code);
 328        show_regs(regs);
 329#endif
 330}
 331
 332int is_valid_bugaddr(unsigned long addr)
 333{
 334        return 1;
 335}
 336
 337static void __kprobes inline do_trap(long interruption_code, int signr,
 338                                        char *str, struct pt_regs *regs,
 339                                        siginfo_t *info)
 340{
 341        /*
 342         * We got all needed information from the lowcore and can
 343         * now safely switch on interrupts.
 344         */
 345        if (regs->psw.mask & PSW_MASK_PSTATE)
 346                local_irq_enable();
 347
 348        if (notify_die(DIE_TRAP, str, regs, interruption_code,
 349                                interruption_code, signr) == NOTIFY_STOP)
 350                return;
 351
 352        if (regs->psw.mask & PSW_MASK_PSTATE) {
 353                struct task_struct *tsk = current;
 354
 355                tsk->thread.trap_no = interruption_code & 0xffff;
 356                force_sig_info(signr, info, tsk);
 357                report_user_fault(interruption_code, regs);
 358        } else {
 359                const struct exception_table_entry *fixup;
 360                fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 361                if (fixup)
 362                        regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 363                else {
 364                        enum bug_trap_type btt;
 365
 366                        btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 367                        if (btt == BUG_TRAP_TYPE_WARN)
 368                                return;
 369                        die(str, regs, interruption_code);
 370                }
 371        }
 372}
 373
 374static inline void __user *get_check_address(struct pt_regs *regs)
 375{
 376        return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 377}
 378
 379void __kprobes do_single_step(struct pt_regs *regs)
 380{
 381        if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 382                                        SIGTRAP) == NOTIFY_STOP){
 383                return;
 384        }
 385        if ((current->ptrace & PT_PTRACED) != 0)
 386                force_sig(SIGTRAP, current);
 387}
 388
 389static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 390{
 391        if (regs->psw.mask & PSW_MASK_PSTATE) {
 392                local_irq_enable();
 393                do_exit(SIGSEGV);
 394                report_user_fault(interruption_code, regs);
 395        } else
 396                die("Unknown program exception", regs, interruption_code);
 397}
 398
 399#define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 400static void name(struct pt_regs * regs, long interruption_code) \
 401{ \
 402        siginfo_t info; \
 403        info.si_signo = signr; \
 404        info.si_errno = 0; \
 405        info.si_code = sicode; \
 406        info.si_addr = siaddr; \
 407        do_trap(interruption_code, signr, str, regs, &info); \
 408}
 409
 410DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 411              ILL_ILLADR, get_check_address(regs))
 412DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 413              ILL_ILLOPN, get_check_address(regs))
 414DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 415              FPE_INTDIV, get_check_address(regs))
 416DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 417              FPE_INTOVF, get_check_address(regs))
 418DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 419              FPE_FLTOVF, get_check_address(regs))
 420DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 421              FPE_FLTUND, get_check_address(regs))
 422DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 423              FPE_FLTRES, get_check_address(regs))
 424DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 425              FPE_FLTDIV, get_check_address(regs))
 426DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 427              FPE_FLTINV, get_check_address(regs))
 428DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 429              ILL_ILLOPN, get_check_address(regs))
 430DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 431              ILL_PRVOPC, get_check_address(regs))
 432DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 433              ILL_ILLOPN, get_check_address(regs))
 434DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 435              ILL_ILLOPN, get_check_address(regs))
 436
 437static inline void
 438do_fp_trap(struct pt_regs *regs, void __user *location,
 439           int fpc, long interruption_code)
 440{
 441        siginfo_t si;
 442
 443        si.si_signo = SIGFPE;
 444        si.si_errno = 0;
 445        si.si_addr = location;
 446        si.si_code = 0;
 447        /* FPC[2] is Data Exception Code */
 448        if ((fpc & 0x00000300) == 0) {
 449                /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 450                if (fpc & 0x8000) /* invalid fp operation */
 451                        si.si_code = FPE_FLTINV;
 452                else if (fpc & 0x4000) /* div by 0 */
 453                        si.si_code = FPE_FLTDIV;
 454                else if (fpc & 0x2000) /* overflow */
 455                        si.si_code = FPE_FLTOVF;
 456                else if (fpc & 0x1000) /* underflow */
 457                        si.si_code = FPE_FLTUND;
 458                else if (fpc & 0x0800) /* inexact */
 459                        si.si_code = FPE_FLTRES;
 460        }
 461        current->thread.ieee_instruction_pointer = (addr_t) location;
 462        do_trap(interruption_code, SIGFPE,
 463                "floating point exception", regs, &si);
 464}
 465
 466static void illegal_op(struct pt_regs * regs, long interruption_code)
 467{
 468        siginfo_t info;
 469        __u8 opcode[6];
 470        __u16 __user *location;
 471        int signal = 0;
 472
 473        location = get_check_address(regs);
 474
 475        /*
 476         * We got all needed information from the lowcore and can
 477         * now safely switch on interrupts.
 478         */
 479        if (regs->psw.mask & PSW_MASK_PSTATE)
 480                local_irq_enable();
 481
 482        if (regs->psw.mask & PSW_MASK_PSTATE) {
 483                if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 484                        return;
 485                if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 486                        if (current->ptrace & PT_PTRACED)
 487                                force_sig(SIGTRAP, current);
 488                        else
 489                                signal = SIGILL;
 490#ifdef CONFIG_MATHEMU
 491                } else if (opcode[0] == 0xb3) {
 492                        if (get_user(*((__u16 *) (opcode+2)), location+1))
 493                                return;
 494                        signal = math_emu_b3(opcode, regs);
 495                } else if (opcode[0] == 0xed) {
 496                        if (get_user(*((__u32 *) (opcode+2)),
 497                                     (__u32 __user *)(location+1)))
 498                                return;
 499                        signal = math_emu_ed(opcode, regs);
 500                } else if (*((__u16 *) opcode) == 0xb299) {
 501                        if (get_user(*((__u16 *) (opcode+2)), location+1))
 502                                return;
 503                        signal = math_emu_srnm(opcode, regs);
 504                } else if (*((__u16 *) opcode) == 0xb29c) {
 505                        if (get_user(*((__u16 *) (opcode+2)), location+1))
 506                                return;
 507                        signal = math_emu_stfpc(opcode, regs);
 508                } else if (*((__u16 *) opcode) == 0xb29d) {
 509                        if (get_user(*((__u16 *) (opcode+2)), location+1))
 510                                return;
 511                        signal = math_emu_lfpc(opcode, regs);
 512#endif
 513                } else
 514                        signal = SIGILL;
 515        } else {
 516                /*
 517                 * If we get an illegal op in kernel mode, send it through the
 518                 * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 519                 */
 520                if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 521                               3, SIGTRAP) != NOTIFY_STOP)
 522                        signal = SIGILL;
 523        }
 524
 525#ifdef CONFIG_MATHEMU
 526        if (signal == SIGFPE)
 527                do_fp_trap(regs, location,
 528                           current->thread.fp_regs.fpc, interruption_code);
 529        else if (signal == SIGSEGV) {
 530                info.si_signo = signal;
 531                info.si_errno = 0;
 532                info.si_code = SEGV_MAPERR;
 533                info.si_addr = (void __user *) location;
 534                do_trap(interruption_code, signal,
 535                        "user address fault", regs, &info);
 536        } else
 537#endif
 538        if (signal) {
 539                info.si_signo = signal;
 540                info.si_errno = 0;
 541                info.si_code = ILL_ILLOPC;
 542                info.si_addr = (void __user *) location;
 543                do_trap(interruption_code, signal,
 544                        "illegal operation", regs, &info);
 545        }
 546}
 547
 548
 549#ifdef CONFIG_MATHEMU
 550asmlinkage void 
 551specification_exception(struct pt_regs * regs, long interruption_code)
 552{
 553        __u8 opcode[6];
 554        __u16 __user *location = NULL;
 555        int signal = 0;
 556
 557        location = (__u16 __user *) get_check_address(regs);
 558
 559        /*
 560         * We got all needed information from the lowcore and can
 561         * now safely switch on interrupts.
 562         */
 563        if (regs->psw.mask & PSW_MASK_PSTATE)
 564                local_irq_enable();
 565
 566        if (regs->psw.mask & PSW_MASK_PSTATE) {
 567                get_user(*((__u16 *) opcode), location);
 568                switch (opcode[0]) {
 569                case 0x28: /* LDR Rx,Ry   */
 570                        signal = math_emu_ldr(opcode);
 571                        break;
 572                case 0x38: /* LER Rx,Ry   */
 573                        signal = math_emu_ler(opcode);
 574                        break;
 575                case 0x60: /* STD R,D(X,B) */
 576                        get_user(*((__u16 *) (opcode+2)), location+1);
 577                        signal = math_emu_std(opcode, regs);
 578                        break;
 579                case 0x68: /* LD R,D(X,B) */
 580                        get_user(*((__u16 *) (opcode+2)), location+1);
 581                        signal = math_emu_ld(opcode, regs);
 582                        break;
 583                case 0x70: /* STE R,D(X,B) */
 584                        get_user(*((__u16 *) (opcode+2)), location+1);
 585                        signal = math_emu_ste(opcode, regs);
 586                        break;
 587                case 0x78: /* LE R,D(X,B) */
 588                        get_user(*((__u16 *) (opcode+2)), location+1);
 589                        signal = math_emu_le(opcode, regs);
 590                        break;
 591                default:
 592                        signal = SIGILL;
 593                        break;
 594                }
 595        } else
 596                signal = SIGILL;
 597
 598        if (signal == SIGFPE)
 599                do_fp_trap(regs, location,
 600                           current->thread.fp_regs.fpc, interruption_code);
 601        else if (signal) {
 602                siginfo_t info;
 603                info.si_signo = signal;
 604                info.si_errno = 0;
 605                info.si_code = ILL_ILLOPN;
 606                info.si_addr = location;
 607                do_trap(interruption_code, signal, 
 608                        "specification exception", regs, &info);
 609        }
 610}
 611#else
 612DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 613              ILL_ILLOPN, get_check_address(regs));
 614#endif
 615
 616static void data_exception(struct pt_regs * regs, long interruption_code)
 617{
 618        __u16 __user *location;
 619        int signal = 0;
 620
 621        location = get_check_address(regs);
 622
 623        /*
 624         * We got all needed information from the lowcore and can
 625         * now safely switch on interrupts.
 626         */
 627        if (regs->psw.mask & PSW_MASK_PSTATE)
 628                local_irq_enable();
 629
 630        if (MACHINE_HAS_IEEE)
 631                asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 632
 633#ifdef CONFIG_MATHEMU
 634        else if (regs->psw.mask & PSW_MASK_PSTATE) {
 635                __u8 opcode[6];
 636                get_user(*((__u16 *) opcode), location);
 637                switch (opcode[0]) {
 638                case 0x28: /* LDR Rx,Ry   */
 639                        signal = math_emu_ldr(opcode);
 640                        break;
 641                case 0x38: /* LER Rx,Ry   */
 642                        signal = math_emu_ler(opcode);
 643                        break;
 644                case 0x60: /* STD R,D(X,B) */
 645                        get_user(*((__u16 *) (opcode+2)), location+1);
 646                        signal = math_emu_std(opcode, regs);
 647                        break;
 648                case 0x68: /* LD R,D(X,B) */
 649                        get_user(*((__u16 *) (opcode+2)), location+1);
 650                        signal = math_emu_ld(opcode, regs);
 651                        break;
 652                case 0x70: /* STE R,D(X,B) */
 653                        get_user(*((__u16 *) (opcode+2)), location+1);
 654                        signal = math_emu_ste(opcode, regs);
 655                        break;
 656                case 0x78: /* LE R,D(X,B) */
 657                        get_user(*((__u16 *) (opcode+2)), location+1);
 658                        signal = math_emu_le(opcode, regs);
 659                        break;
 660                case 0xb3:
 661                        get_user(*((__u16 *) (opcode+2)), location+1);
 662                        signal = math_emu_b3(opcode, regs);
 663                        break;
 664                case 0xed:
 665                        get_user(*((__u32 *) (opcode+2)),
 666                                 (__u32 __user *)(location+1));
 667                        signal = math_emu_ed(opcode, regs);
 668                        break;
 669                case 0xb2:
 670                        if (opcode[1] == 0x99) {
 671                                get_user(*((__u16 *) (opcode+2)), location+1);
 672                                signal = math_emu_srnm(opcode, regs);
 673                        } else if (opcode[1] == 0x9c) {
 674                                get_user(*((__u16 *) (opcode+2)), location+1);
 675                                signal = math_emu_stfpc(opcode, regs);
 676                        } else if (opcode[1] == 0x9d) {
 677                                get_user(*((__u16 *) (opcode+2)), location+1);
 678                                signal = math_emu_lfpc(opcode, regs);
 679                        } else
 680                                signal = SIGILL;
 681                        break;
 682                default:
 683                        signal = SIGILL;
 684                        break;
 685                }
 686        }
 687#endif 
 688        if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 689                signal = SIGFPE;
 690        else
 691                signal = SIGILL;
 692        if (signal == SIGFPE)
 693                do_fp_trap(regs, location,
 694                           current->thread.fp_regs.fpc, interruption_code);
 695        else if (signal) {
 696                siginfo_t info;
 697                info.si_signo = signal;
 698                info.si_errno = 0;
 699                info.si_code = ILL_ILLOPN;
 700                info.si_addr = location;
 701                do_trap(interruption_code, signal, 
 702                        "data exception", regs, &info);
 703        }
 704}
 705
 706static void space_switch_exception(struct pt_regs * regs, long int_code)
 707{
 708        siginfo_t info;
 709
 710        /* Set user psw back to home space mode. */
 711        if (regs->psw.mask & PSW_MASK_PSTATE)
 712                regs->psw.mask |= PSW_ASC_HOME;
 713        /* Send SIGILL. */
 714        info.si_signo = SIGILL;
 715        info.si_errno = 0;
 716        info.si_code = ILL_PRVOPC;
 717        info.si_addr = get_check_address(regs);
 718        do_trap(int_code, SIGILL, "space switch event", regs, &info);
 719}
 720
 721asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 722{
 723        bust_spinlocks(1);
 724        printk("Kernel stack overflow.\n");
 725        show_regs(regs);
 726        bust_spinlocks(0);
 727        panic("Corrupt kernel stack, can't continue.");
 728}
 729
 730/* init is done in lowcore.S and head.S */
 731
 732void __init trap_init(void)
 733{
 734        int i;
 735
 736        for (i = 0; i < 128; i++)
 737          pgm_check_table[i] = &default_trap_handler;
 738        pgm_check_table[1] = &illegal_op;
 739        pgm_check_table[2] = &privileged_op;
 740        pgm_check_table[3] = &execute_exception;
 741        pgm_check_table[4] = &do_protection_exception;
 742        pgm_check_table[5] = &addressing_exception;
 743        pgm_check_table[6] = &specification_exception;
 744        pgm_check_table[7] = &data_exception;
 745        pgm_check_table[8] = &overflow_exception;
 746        pgm_check_table[9] = &divide_exception;
 747        pgm_check_table[0x0A] = &overflow_exception;
 748        pgm_check_table[0x0B] = &divide_exception;
 749        pgm_check_table[0x0C] = &hfp_overflow_exception;
 750        pgm_check_table[0x0D] = &hfp_underflow_exception;
 751        pgm_check_table[0x0E] = &hfp_significance_exception;
 752        pgm_check_table[0x0F] = &hfp_divide_exception;
 753        pgm_check_table[0x10] = &do_dat_exception;
 754        pgm_check_table[0x11] = &do_dat_exception;
 755        pgm_check_table[0x12] = &translation_exception;
 756        pgm_check_table[0x13] = &special_op_exception;
 757#ifdef CONFIG_64BIT
 758        pgm_check_table[0x38] = &do_asce_exception;
 759        pgm_check_table[0x39] = &do_dat_exception;
 760        pgm_check_table[0x3A] = &do_dat_exception;
 761        pgm_check_table[0x3B] = &do_dat_exception;
 762#endif /* CONFIG_64BIT */
 763        pgm_check_table[0x15] = &operand_exception;
 764        pgm_check_table[0x1C] = &space_switch_exception;
 765        pgm_check_table[0x1D] = &hfp_sqrt_exception;
 766        pfault_irq_init();
 767}
 768