arch/s390/kernel/traps.c

   1 /*
   2  *  arch/s390/kernel/traps.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7  *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   8  *
   9  *  Derived from "arch/i386/kernel/traps.c"
  10  *    Copyright (C) 1991, 1992 Linus Torvalds
  11  */
  12
  13 /*
  14  * 'Traps.c' handles hardware traps and faults after we have saved some
  15  * state in 'asm.s'.
  16  */
  17 #include <linux/sched.h>
  18 #include <linux/kernel.h>
  19 #include <linux/string.h>
  20 #include <linux/errno.h>
  21 #include <linux/ptrace.h>
  22 #include <linux/timer.h>
  23 #include <linux/mm.h>
  24 #include <linux/smp.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/delay.h>
  29 #include <linux/module.h>
  30 #include <linux/kdebug.h>
  31 #include <linux/kallsyms.h>
  32 #include <linux/reboot.h>
  33 #include <linux/kprobes.h>
  34 #include <linux/bug.h>
  35 #include <linux/utsname.h>
  36 #include <asm/system.h>
  37 #include <asm/uaccess.h>
  38 #include <asm/io.h>
  39 #include <asm/atomic.h>
  40 #include <asm/mathemu.h>
  41 #include <asm/cpcmd.h>
  42 #include <asm/s390_ext.h>
  43 #include <asm/lowcore.h>
  44 #include <asm/debug.h>
  45 #include "entry.h"
  46
  47 pgm_check_handler_t *pgm_check_table[128];
  48
  49 #ifdef CONFIG_SYSCTL
  50 #ifdef CONFIG_PROCESS_DEBUG
  51 int sysctl_userprocess_debug = 1;
  52 #else
  53 int sysctl_userprocess_debug = 0;
  54 #endif
  55 #endif
  56
  57 extern pgm_check_handler_t do_protection_exception;
  58 extern pgm_check_handler_t do_dat_exception;
  59 extern 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 FOURLONG "%08lx %08lx %08lx %08lx\n"
  65 static int kstack_depth_to_print = 12;
  66 #else /* CONFIG_64BIT */
  67 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  68 static int kstack_depth_to_print = 20;
  69 #endif /* CONFIG_64BIT */
  70
  71 /*
  72  * For show_trace we have tree different stack to consider:
  73  *   - the panic stack which is used if the kernel stack has overflown
  74  *   - the asynchronous interrupt stack (cpu related)
  75  *   - the synchronous kernel stack (process related)
  76  * The stack trace can start at any of the three stack and can potentially
  77  * touch all of them. The order is: panic stack, async stack, sync stack.
  78  */
  79 static unsigned long
  80 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  81 {
  82         struct stack_frame *sf;
  83         struct pt_regs *regs;
  84
  85         while (1) {
  86                 sp = sp & PSW_ADDR_INSN;
  87                 if (sp < low || sp > high - sizeof(*sf))
  88                         return sp;
  89                 sf = (struct stack_frame *) sp;
  90                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  91                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
  92                 /* Follow the backchain. */
  93                 while (1) {
  94                         low = sp;
  95                         sp = sf->back_chain & PSW_ADDR_INSN;
  96                         if (!sp)
  97                                 break;
  98                         if (sp <= low || sp > high - sizeof(*sf))
  99                                 return sp;
 100                         sf = (struct stack_frame *) sp;
 101                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 102                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 103                 }
 104                 /* Zero backchain detected, check for interrupt frame. */
 105                 sp = (unsigned long) (sf + 1);
 106                 if (sp <= low || sp > high - sizeof(*regs))
 107                         return sp;
 108                 regs = (struct pt_regs *) sp;
 109                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 110                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 111                 low = sp;
 112                 sp = regs->gprs[15];
 113         }
 114 }
 115
 116 void show_trace(struct task_struct *task, unsigned long *stack)
 117 {
 118         register unsigned long __r15 asm ("15");
 119         unsigned long sp;
 120
 121         sp = (unsigned long) stack;
 122         if (!sp)
 123                 sp = task ? task->thread.ksp : __r15;
 124         printk("Call Trace:\n");
 125 #ifdef CONFIG_CHECK_STACK
 126         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
 127                           S390_lowcore.panic_stack);
 128 #endif
 129         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
 130                           S390_lowcore.async_stack);
 131         if (task)
 132                 __show_trace(sp, (unsigned long) task_stack_page(task),
 133                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
 134         else
 135                 __show_trace(sp, S390_lowcore.thread_info,
 136                              S390_lowcore.thread_info + THREAD_SIZE);
 137         if (!task)
 138                 task = current;
 139         debug_show_held_locks(task);
 140 }
 141
 142 void show_stack(struct task_struct *task, unsigned long *sp)
 143 {
 144         register unsigned long * __r15 asm ("15");
 145         unsigned long *stack;
 146         int i;
 147
 148         if (!sp)
 149                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
 150         else
 151                 stack = sp;
 152
 153         for (i = 0; i < kstack_depth_to_print; i++) {
 154                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
 155                         break;
 156                 if (i && ((i * sizeof (long) % 32) == 0))
 157                         printk("\n       ");
 158                 printk("%p ", (void *)*stack++);
 159         }
 160         printk("\n");
 161         show_trace(task, sp);
 162 }
 163
 164 #ifdef CONFIG_64BIT
 165 void show_last_breaking_event(struct pt_regs *regs)
 166 {
 167         printk("Last Breaking-Event-Address:\n");
 168         printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
 169         print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
 170 }
 171 #endif
 172
 173 /*
 174  * The architecture-independent dump_stack generator
 175  */
 176 void dump_stack(void)
 177 {
 178         printk("CPU: %d %s %s %.*s\n",
 179                task_thread_info(current)->cpu, print_tainted(),
 180                init_utsname()->release,
 181                (int)strcspn(init_utsname()->version, " "),
 182                init_utsname()->version);
 183         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 184                current->comm, current->pid, current,
 185                (void *) current->thread.ksp);
 186         show_stack(NULL, NULL);
 187 }
 188 EXPORT_SYMBOL(dump_stack);
 189
 190 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 191 {
 192         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 193 }
 194
 195 void show_registers(struct pt_regs *regs)
 196 {
 197         char *mode;
 198
 199         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
 200         printk("%s PSW : %p %p",
 201                mode, (void *) regs->psw.mask,
 202                (void *) regs->psw.addr);
 203         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
 204         printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
 205                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
 206                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
 207                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
 208                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
 209                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
 210                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
 211 #ifdef CONFIG_64BIT
 212         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
 213 #endif
 214         printk("\n%s GPRS: " FOURLONG, mode,
 215                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
 216         printk("           " FOURLONG,
 217                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
 218         printk("           " FOURLONG,
 219                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
 220         printk("           " FOURLONG,
 221                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
 222
 223         show_code(regs);
 224 }
 225
 226 /* This is called from fs/proc/array.c */
 227 void task_show_regs(struct seq_file *m, struct task_struct *task)
 228 {
 229         struct pt_regs *regs;
 230
 231         regs = task_pt_regs(task);
 232         seq_printf(m, "task: %p, ksp: %p\n",
 233                        task, (void *)task->thread.ksp);
 234         seq_printf(m, "User PSW : %p %p\n",
 235                        (void *) regs->psw.mask, (void *)regs->psw.addr);
 236
 237         seq_printf(m, "User GPRS: " FOURLONG,
 238                           regs->gprs[0], regs->gprs[1],
 239                           regs->gprs[2], regs->gprs[3]);
 240         seq_printf(m, "           " FOURLONG,
 241                           regs->gprs[4], regs->gprs[5],
 242                           regs->gprs[6], regs->gprs[7]);
 243         seq_printf(m, "           " FOURLONG,
 244                           regs->gprs[8], regs->gprs[9],
 245                           regs->gprs[10], regs->gprs[11]);
 246         seq_printf(m, "           " FOURLONG,
 247                           regs->gprs[12], regs->gprs[13],
 248                           regs->gprs[14], regs->gprs[15]);
 249         seq_printf(m, "User ACRS: %08x %08x %08x %08x\n",
 250                           task->thread.acrs[0], task->thread.acrs[1],
 251                           task->thread.acrs[2], task->thread.acrs[3]);
 252         seq_printf(m, "           %08x %08x %08x %08x\n",
 253                           task->thread.acrs[4], task->thread.acrs[5],
 254                           task->thread.acrs[6], task->thread.acrs[7]);
 255         seq_printf(m, "           %08x %08x %08x %08x\n",
 256                           task->thread.acrs[8], task->thread.acrs[9],
 257                           task->thread.acrs[10], task->thread.acrs[11]);
 258         seq_printf(m, "           %08x %08x %08x %08x\n",
 259                           task->thread.acrs[12], task->thread.acrs[13],
 260                           task->thread.acrs[14], task->thread.acrs[15]);
 261 }
 262
 263 static DEFINE_SPINLOCK(die_lock);
 264
 265 void die(const char * str, struct pt_regs * regs, long err)
 266 {
 267         static int die_counter;
 268
 269         oops_enter();
 270         debug_stop_all();
 271         console_verbose();
 272         spin_lock_irq(&die_lock);
 273         bust_spinlocks(1);
 274         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
 275 #ifdef CONFIG_PREEMPT
 276         printk("PREEMPT ");
 277 #endif
 278 #ifdef CONFIG_SMP
 279         printk("SMP ");
 280 #endif
 281 #ifdef CONFIG_DEBUG_PAGEALLOC
 282         printk("DEBUG_PAGEALLOC");
 283 #endif
 284         printk("\n");
 285         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
 286         show_regs(regs);
 287         bust_spinlocks(0);
 288         add_taint(TAINT_DIE);
 289         spin_unlock_irq(&die_lock);
 290         if (in_interrupt())
 291                 panic("Fatal exception in interrupt");
 292         if (panic_on_oops)
 293                 panic("Fatal exception: panic_on_oops");
 294         oops_exit();
 295         do_exit(SIGSEGV);
 296 }
 297
 298 static void inline
 299 report_user_fault(long interruption_code, struct pt_regs *regs)
 300 {
 301 #if defined(CONFIG_SYSCTL)
 302         if (!sysctl_userprocess_debug)
 303                 return;
 304 #endif
 305 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
 306         printk("User process fault: interruption code 0x%lX\n",
 307                interruption_code);
 308         show_regs(regs);
 309 #endif
 310 }
 311
 312 int is_valid_bugaddr(unsigned long addr)
 313 {
 314         return 1;
 315 }
 316
 317 static void __kprobes inline do_trap(long interruption_code, int signr,
 318                                         char *str, struct pt_regs *regs,
 319                                         siginfo_t *info)
 320 {
 321         /*
 322          * We got all needed information from the lowcore and can
 323          * now safely switch on interrupts.
 324          */
 325         if (regs->psw.mask & PSW_MASK_PSTATE)
 326                 local_irq_enable();
 327
 328         if (notify_die(DIE_TRAP, str, regs, interruption_code,
 329                                 interruption_code, signr) == NOTIFY_STOP)
 330                 return;
 331
 332         if (regs->psw.mask & PSW_MASK_PSTATE) {
 333                 struct task_struct *tsk = current;
 334
 335                 tsk->thread.trap_no = interruption_code & 0xffff;
 336                 force_sig_info(signr, info, tsk);
 337                 report_user_fault(interruption_code, regs);
 338         } else {
 339                 const struct exception_table_entry *fixup;
 340                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 341                 if (fixup)
 342                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 343                 else {
 344                         enum bug_trap_type btt;
 345
 346                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 347                         if (btt == BUG_TRAP_TYPE_WARN)
 348                                 return;
 349                         die(str, regs, interruption_code);
 350                 }
 351         }
 352 }
 353
 354 static inline void __user *get_check_address(struct pt_regs *regs)
 355 {
 356         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
 357 }
 358
 359 void __kprobes do_single_step(struct pt_regs *regs)
 360 {
 361         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
 362                                         SIGTRAP) == NOTIFY_STOP){
 363                 return;
 364         }
 365         if ((current->ptrace & PT_PTRACED) != 0)
 366                 force_sig(SIGTRAP, current);
 367 }
 368
 369 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
 370 {
 371         if (regs->psw.mask & PSW_MASK_PSTATE) {
 372                 local_irq_enable();
 373                 do_exit(SIGSEGV);
 374                 report_user_fault(interruption_code, regs);
 375         } else
 376                 die("Unknown program exception", regs, interruption_code);
 377 }
 378
 379 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
 380 static void name(struct pt_regs * regs, long interruption_code) \
 381 { \
 382         siginfo_t info; \
 383         info.si_signo = signr; \
 384         info.si_errno = 0; \
 385         info.si_code = sicode; \
 386         info.si_addr = siaddr; \
 387         do_trap(interruption_code, signr, str, regs, &info); \
 388 }
 389
 390 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 391               ILL_ILLADR, get_check_address(regs))
 392 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 393               ILL_ILLOPN, get_check_address(regs))
 394 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 395               FPE_INTDIV, get_check_address(regs))
 396 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 397               FPE_INTOVF, get_check_address(regs))
 398 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 399               FPE_FLTOVF, get_check_address(regs))
 400 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 401               FPE_FLTUND, get_check_address(regs))
 402 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 403               FPE_FLTRES, get_check_address(regs))
 404 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 405               FPE_FLTDIV, get_check_address(regs))
 406 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 407               FPE_FLTINV, get_check_address(regs))
 408 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 409               ILL_ILLOPN, get_check_address(regs))
 410 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 411               ILL_PRVOPC, get_check_address(regs))
 412 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 413               ILL_ILLOPN, get_check_address(regs))
 414 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 415               ILL_ILLOPN, get_check_address(regs))
 416
 417 static inline void
 418 do_fp_trap(struct pt_regs *regs, void __user *location,
 419            int fpc, long interruption_code)
 420 {
 421         siginfo_t si;
 422
 423         si.si_signo = SIGFPE;
 424         si.si_errno = 0;
 425         si.si_addr = location;
 426         si.si_code = 0;
 427         /* FPC[2] is Data Exception Code */
 428         if ((fpc & 0x00000300) == 0) {
 429                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
 430                 if (fpc & 0x8000) /* invalid fp operation */
 431                         si.si_code = FPE_FLTINV;
 432                 else if (fpc & 0x4000) /* div by 0 */
 433                         si.si_code = FPE_FLTDIV;
 434                 else if (fpc & 0x2000) /* overflow */
 435                         si.si_code = FPE_FLTOVF;
 436                 else if (fpc & 0x1000) /* underflow */
 437                         si.si_code = FPE_FLTUND;
 438                 else if (fpc & 0x0800) /* inexact */
 439                         si.si_code = FPE_FLTRES;
 440         }
 441         current->thread.ieee_instruction_pointer = (addr_t) location;
 442         do_trap(interruption_code, SIGFPE,
 443                 "floating point exception", regs, &si);
 444 }
 445
 446 static void illegal_op(struct pt_regs * regs, long interruption_code)
 447 {
 448         siginfo_t info;
 449         __u8 opcode[6];
 450         __u16 __user *location;
 451         int signal = 0;
 452
 453         location = get_check_address(regs);
 454
 455         /*
 456          * We got all needed information from the lowcore and can
 457          * now safely switch on interrupts.
 458          */
 459         if (regs->psw.mask & PSW_MASK_PSTATE)
 460                 local_irq_enable();
 461
 462         if (regs->psw.mask & PSW_MASK_PSTATE) {
 463                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 464                         return;
 465                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 466                         if (current->ptrace & PT_PTRACED)
 467                                 force_sig(SIGTRAP, current);
 468                         else
 469                                 signal = SIGILL;
 470 #ifdef CONFIG_MATHEMU
 471                 } else if (opcode[0] == 0xb3) {
 472                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 473                                 return;
 474                         signal = math_emu_b3(opcode, regs);
 475                 } else if (opcode[0] == 0xed) {
 476                         if (get_user(*((__u32 *) (opcode+2)),
 477                                      (__u32 __user *)(location+1)))
 478                                 return;
 479                         signal = math_emu_ed(opcode, regs);
 480                 } else if (*((__u16 *) opcode) == 0xb299) {
 481                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 482                                 return;
 483                         signal = math_emu_srnm(opcode, regs);
 484                 } else if (*((__u16 *) opcode) == 0xb29c) {
 485                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 486                                 return;
 487                         signal = math_emu_stfpc(opcode, regs);
 488                 } else if (*((__u16 *) opcode) == 0xb29d) {
 489                         if (get_user(*((__u16 *) (opcode+2)), location+1))
 490                                 return;
 491                         signal = math_emu_lfpc(opcode, regs);
 492 #endif
 493                 } else
 494                         signal = SIGILL;
 495         } else {
 496                 /*
 497                  * If we get an illegal op in kernel mode, send it through the
 498                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
 499                  */
 500                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
 501                                3, SIGTRAP) != NOTIFY_STOP)
 502                         signal = SIGILL;
 503         }
 504
 505 #ifdef CONFIG_MATHEMU
 506         if (signal == SIGFPE)
 507                 do_fp_trap(regs, location,
 508                            current->thread.fp_regs.fpc, interruption_code);
 509         else if (signal == SIGSEGV) {
 510                 info.si_signo = signal;
 511                 info.si_errno = 0;
 512                 info.si_code = SEGV_MAPERR;
 513                 info.si_addr = (void __user *) location;
 514                 do_trap(interruption_code, signal,
 515                         "user address fault", regs, &info);
 516         } else
 517 #endif
 518         if (signal) {
 519                 info.si_signo = signal;
 520                 info.si_errno = 0;
 521                 info.si_code = ILL_ILLOPC;
 522                 info.si_addr = (void __user *) location;
 523                 do_trap(interruption_code, signal,
 524                         "illegal operation", regs, &info);
 525         }
 526 }
 527
 528
 529 #ifdef CONFIG_MATHEMU
 530 asmlinkage void
 531 specification_exception(struct pt_regs * regs, long interruption_code)
 532 {
 533         __u8 opcode[6];
 534         __u16 __user *location = NULL;
 535         int signal = 0;
 536
 537         location = (__u16 __user *) get_check_address(regs);
 538
 539         /*
 540          * We got all needed information from the lowcore and can
 541          * now safely switch on interrupts.
 542          */
 543         if (regs->psw.mask & PSW_MASK_PSTATE)
 544                 local_irq_enable();
 545
 546         if (regs->psw.mask & PSW_MASK_PSTATE) {
 547                 get_user(*((__u16 *) opcode), location);
 548                 switch (opcode[0]) {
 549                 case 0x28: /* LDR Rx,Ry   */
 550                         signal = math_emu_ldr(opcode);
 551                         break;
 552                 case 0x38: /* LER Rx,Ry   */
 553                         signal = math_emu_ler(opcode);
 554                         break;
 555                 case 0x60: /* STD R,D(X,B) */
 556                         get_user(*((__u16 *) (opcode+2)), location+1);
 557                         signal = math_emu_std(opcode, regs);
 558                         break;
 559                 case 0x68: /* LD R,D(X,B) */
 560                         get_user(*((__u16 *) (opcode+2)), location+1);
 561                         signal = math_emu_ld(opcode, regs);
 562                         break;
 563                 case 0x70: /* STE R,D(X,B) */
 564                         get_user(*((__u16 *) (opcode+2)), location+1);
 565                         signal = math_emu_ste(opcode, regs);
 566                         break;
 567                 case 0x78: /* LE R,D(X,B) */
 568                         get_user(*((__u16 *) (opcode+2)), location+1);
 569                         signal = math_emu_le(opcode, regs);
 570                         break;
 571                 default:
 572                         signal = SIGILL;
 573                         break;
 574                 }
 575         } else
 576                 signal = SIGILL;
 577
 578         if (signal == SIGFPE)
 579                 do_fp_trap(regs, location,
 580                            current->thread.fp_regs.fpc, interruption_code);
 581         else if (signal) {
 582                 siginfo_t info;
 583                 info.si_signo = signal;
 584                 info.si_errno = 0;
 585                 info.si_code = ILL_ILLOPN;
 586                 info.si_addr = location;
 587                 do_trap(interruption_code, signal,
 588                         "specification exception", regs, &info);
 589         }
 590 }
 591 #else
 592 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 593               ILL_ILLOPN, get_check_address(regs));
 594 #endif
 595
 596 static void data_exception(struct pt_regs * regs, long interruption_code)
 597 {
 598         __u16 __user *location;
 599         int signal = 0;
 600
 601         location = get_check_address(regs);
 602
 603         /*
 604          * We got all needed information from the lowcore and can
 605          * now safely switch on interrupts.
 606          */
 607         if (regs->psw.mask & PSW_MASK_PSTATE)
 608                 local_irq_enable();
 609
 610         if (MACHINE_HAS_IEEE)
 611                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 612
 613 #ifdef CONFIG_MATHEMU
 614         else if (regs->psw.mask & PSW_MASK_PSTATE) {
 615                 __u8 opcode[6];
 616                 get_user(*((__u16 *) opcode), location);
 617                 switch (opcode[0]) {
 618                 case 0x28: /* LDR Rx,Ry   */
 619                         signal = math_emu_ldr(opcode);
 620                         break;
 621                 case 0x38: /* LER Rx,Ry   */
 622                         signal = math_emu_ler(opcode);
 623                         break;
 624                 case 0x60: /* STD R,D(X,B) */
 625                         get_user(*((__u16 *) (opcode+2)), location+1);
 626                         signal = math_emu_std(opcode, regs);
 627                         break;
 628                 case 0x68: /* LD R,D(X,B) */
 629                         get_user(*((__u16 *) (opcode+2)), location+1);
 630                         signal = math_emu_ld(opcode, regs);
 631                         break;
 632                 case 0x70: /* STE R,D(X,B) */
 633                         get_user(*((__u16 *) (opcode+2)), location+1);
 634                         signal = math_emu_ste(opcode, regs);
 635                         break;
 636                 case 0x78: /* LE R,D(X,B) */
 637                         get_user(*((__u16 *) (opcode+2)), location+1);
 638                         signal = math_emu_le(opcode, regs);
 639                         break;
 640                 case 0xb3:
 641                         get_user(*((__u16 *) (opcode+2)), location+1);
 642                         signal = math_emu_b3(opcode, regs);
 643                         break;
 644                 case 0xed:
 645                         get_user(*((__u32 *) (opcode+2)),
 646                                  (__u32 __user *)(location+1));
 647                         signal = math_emu_ed(opcode, regs);
 648                         break;
 649                 case 0xb2:
 650                         if (opcode[1] == 0x99) {
 651                                 get_user(*((__u16 *) (opcode+2)), location+1);
 652                                 signal = math_emu_srnm(opcode, regs);
 653                         } else if (opcode[1] == 0x9c) {
 654                                 get_user(*((__u16 *) (opcode+2)), location+1);
 655                                 signal = math_emu_stfpc(opcode, regs);
 656                         } else if (opcode[1] == 0x9d) {
 657                                 get_user(*((__u16 *) (opcode+2)), location+1);
 658                                 signal = math_emu_lfpc(opcode, regs);
 659                         } else
 660                                 signal = SIGILL;
 661                         break;
 662                 default:
 663                         signal = SIGILL;
 664                         break;
 665                 }
 666         }
 667 #endif
 668         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
 669                 signal = SIGFPE;
 670         else
 671                 signal = SIGILL;
 672         if (signal == SIGFPE)
 673                 do_fp_trap(regs, location,
 674                            current->thread.fp_regs.fpc, interruption_code);
 675         else if (signal) {
 676                 siginfo_t info;
 677                 info.si_signo = signal;
 678                 info.si_errno = 0;
 679                 info.si_code = ILL_ILLOPN;
 680                 info.si_addr = location;
 681                 do_trap(interruption_code, signal,
 682                         "data exception", regs, &info);
 683         }
 684 }
 685
 686 static void space_switch_exception(struct pt_regs * regs, long int_code)
 687 {
 688         siginfo_t info;
 689
 690         /* Set user psw back to home space mode. */
 691         if (regs->psw.mask & PSW_MASK_PSTATE)
 692                 regs->psw.mask |= PSW_ASC_HOME;
 693         /* Send SIGILL. */
 694         info.si_signo = SIGILL;
 695         info.si_errno = 0;
 696         info.si_code = ILL_PRVOPC;
 697         info.si_addr = get_check_address(regs);
 698         do_trap(int_code, SIGILL, "space switch event", regs, &info);
 699 }
 700
 701 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
 702 {
 703         bust_spinlocks(1);
 704         printk("Kernel stack overflow.\n");
 705         show_regs(regs);
 706         bust_spinlocks(0);
 707         panic("Corrupt kernel stack, can't continue.");
 708 }
 709
 710 /* init is done in lowcore.S and head.S */
 711
 712 void __init trap_init(void)
 713 {
 714         int i;
 715
 716         for (i = 0; i < 128; i++)
 717           pgm_check_table[i] = &default_trap_handler;
 718         pgm_check_table[1] = &illegal_op;
 719         pgm_check_table[2] = &privileged_op;
 720         pgm_check_table[3] = &execute_exception;
 721         pgm_check_table[4] = &do_protection_exception;
 722         pgm_check_table[5] = &addressing_exception;
 723         pgm_check_table[6] = &specification_exception;
 724         pgm_check_table[7] = &data_exception;
 725         pgm_check_table[8] = &overflow_exception;
 726         pgm_check_table[9] = &divide_exception;
 727         pgm_check_table[0x0A] = &overflow_exception;
 728         pgm_check_table[0x0B] = &divide_exception;
 729         pgm_check_table[0x0C] = &hfp_overflow_exception;
 730         pgm_check_table[0x0D] = &hfp_underflow_exception;
 731         pgm_check_table[0x0E] = &hfp_significance_exception;
 732         pgm_check_table[0x0F] = &hfp_divide_exception;
 733         pgm_check_table[0x10] = &do_dat_exception;
 734         pgm_check_table[0x11] = &do_dat_exception;
 735         pgm_check_table[0x12] = &translation_exception;
 736         pgm_check_table[0x13] = &special_op_exception;
 737 #ifdef CONFIG_64BIT
 738         pgm_check_table[0x38] = &do_asce_exception;
 739         pgm_check_table[0x39] = &do_dat_exception;
 740         pgm_check_table[0x3A] = &do_dat_exception;
 741         pgm_check_table[0x3B] = &do_dat_exception;
 742 #endif /* CONFIG_64BIT */
 743         pgm_check_table[0x15] = &operand_exception;
 744         pgm_check_table[0x1C] = &space_switch_exception;
 745         pgm_check_table[0x1D] = &hfp_sqrt_exception;
 746         pfault_irq_init();
 747 }