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/tracehook.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 LONG "%08lx "
  65 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
  66 static int kstack_depth_to_print = 12;
  67 #else /* CONFIG_64BIT */
  68 #define LONG "%016lx "
  69 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
  70 static int kstack_depth_to_print = 20;
  71 #endif /* CONFIG_64BIT */
  72
  73 /*
  74  * For show_trace we have tree different stack to consider:
  75  *   - the panic stack which is used if the kernel stack has overflown
  76  *   - the asynchronous interrupt stack (cpu related)
  77  *   - the synchronous kernel stack (process related)
  78  * The stack trace can start at any of the three stack and can potentially
  79  * touch all of them. The order is: panic stack, async stack, sync stack.
  80  */
  81 static unsigned long
  82 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
  83 {
  84         struct stack_frame *sf;
  85         struct pt_regs *regs;
  86
  87         while (1) {
  88                 sp = sp & PSW_ADDR_INSN;
  89                 if (sp < low || sp > high - sizeof(*sf))
  90                         return sp;
  91                 sf = (struct stack_frame *) sp;
  92                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
  93                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
  94                 /* Follow the backchain. */
  95                 while (1) {
  96                         low = sp;
  97                         sp = sf->back_chain & PSW_ADDR_INSN;
  98                         if (!sp)
  99                                 break;
 100                         if (sp <= low || sp > high - sizeof(*sf))
 101                                 return sp;
 102                         sf = (struct stack_frame *) sp;
 103                         printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
 104                         print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
 105                 }
 106                 /* Zero backchain detected, check for interrupt frame. */
 107                 sp = (unsigned long) (sf + 1);
 108                 if (sp <= low || sp > high - sizeof(*regs))
 109                         return sp;
 110                 regs = (struct pt_regs *) sp;
 111                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
 112                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
 113                 low = sp;
 114                 sp = regs->gprs[15];
 115         }
 116 }
 117
 118 static 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
 144 void 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
 166 static 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  */
 178 void 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 }
 190 EXPORT_SYMBOL(dump_stack);
 191
 192 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
 193 {
 194         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
 195 }
 196
 197 void 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
 228 void 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 */
 247 void 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
 283 static DEFINE_SPINLOCK(die_lock);
 284
 285 void 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
 318 static void inline
 319 report_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
 332 int is_valid_bugaddr(unsigned long addr)
 333 {
 334         return 1;
 335 }
 336
 337 static 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
 374 static 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
 379 void __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 (tracehook_consider_fatal_signal(current, SIGTRAP))
 386                 force_sig(SIGTRAP, current);
 387 }
 388
 389 static 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) \
 400 static 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
 410 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
 411               ILL_ILLADR, get_check_address(regs))
 412 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
 413               ILL_ILLOPN, get_check_address(regs))
 414 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
 415               FPE_INTDIV, get_check_address(regs))
 416 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
 417               FPE_INTOVF, get_check_address(regs))
 418 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
 419               FPE_FLTOVF, get_check_address(regs))
 420 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
 421               FPE_FLTUND, get_check_address(regs))
 422 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
 423               FPE_FLTRES, get_check_address(regs))
 424 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
 425               FPE_FLTDIV, get_check_address(regs))
 426 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
 427               FPE_FLTINV, get_check_address(regs))
 428 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
 429               ILL_ILLOPN, get_check_address(regs))
 430 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
 431               ILL_PRVOPC, get_check_address(regs))
 432 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
 433               ILL_ILLOPN, get_check_address(regs))
 434 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
 435               ILL_ILLOPN, get_check_address(regs))
 436
 437 static inline void
 438 do_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
 466 static 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 (tracehook_consider_fatal_signal(current, SIGTRAP))
 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
 550 asmlinkage void
 551 specification_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
 612 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
 613               ILL_ILLOPN, get_check_address(regs));
 614 #endif
 615
 616 static 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
 706 static 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
 721 asmlinkage 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
 732 void __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 }