atomic: use <linux/atomic.h>
[linux-2.6.git] / 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 <linux/atomic.h>
40 #include <asm/mathemu.h>
41 #include <asm/cpcmd.h>
42 #include <asm/lowcore.h>
43 #include <asm/debug.h>
44 #include "entry.h"
45
46 void (*pgm_check_table[128])(struct pt_regs *, long, unsigned long);
47
48 int show_unhandled_signals;
49
50 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
51
52 #ifndef CONFIG_64BIT
53 #define LONG "%08lx "
54 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
55 static int kstack_depth_to_print = 12;
56 #else /* CONFIG_64BIT */
57 #define LONG "%016lx "
58 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
59 static int kstack_depth_to_print = 20;
60 #endif /* CONFIG_64BIT */
61
62 /*
63  * For show_trace we have tree different stack to consider:
64  *   - the panic stack which is used if the kernel stack has overflown
65  *   - the asynchronous interrupt stack (cpu related)
66  *   - the synchronous kernel stack (process related)
67  * The stack trace can start at any of the three stack and can potentially
68  * touch all of them. The order is: panic stack, async stack, sync stack.
69  */
70 static unsigned long
71 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
72 {
73         struct stack_frame *sf;
74         struct pt_regs *regs;
75
76         while (1) {
77                 sp = sp & PSW_ADDR_INSN;
78                 if (sp < low || sp > high - sizeof(*sf))
79                         return sp;
80                 sf = (struct stack_frame *) sp;
81                 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
82                 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
83                 /* Follow the backchain. */
84                 while (1) {
85                         low = sp;
86                         sp = sf->back_chain & PSW_ADDR_INSN;
87                         if (!sp)
88                                 break;
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                 }
95                 /* Zero backchain detected, check for interrupt frame. */
96                 sp = (unsigned long) (sf + 1);
97                 if (sp <= low || sp > high - sizeof(*regs))
98                         return sp;
99                 regs = (struct pt_regs *) sp;
100                 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
101                 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
102                 low = sp;
103                 sp = regs->gprs[15];
104         }
105 }
106
107 static void show_trace(struct task_struct *task, unsigned long *stack)
108 {
109         register unsigned long __r15 asm ("15");
110         unsigned long sp;
111
112         sp = (unsigned long) stack;
113         if (!sp)
114                 sp = task ? task->thread.ksp : __r15;
115         printk("Call Trace:\n");
116 #ifdef CONFIG_CHECK_STACK
117         sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
118                           S390_lowcore.panic_stack);
119 #endif
120         sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
121                           S390_lowcore.async_stack);
122         if (task)
123                 __show_trace(sp, (unsigned long) task_stack_page(task),
124                              (unsigned long) task_stack_page(task) + THREAD_SIZE);
125         else
126                 __show_trace(sp, S390_lowcore.thread_info,
127                              S390_lowcore.thread_info + THREAD_SIZE);
128         if (!task)
129                 task = current;
130         debug_show_held_locks(task);
131 }
132
133 void show_stack(struct task_struct *task, unsigned long *sp)
134 {
135         register unsigned long * __r15 asm ("15");
136         unsigned long *stack;
137         int i;
138
139         if (!sp)
140                 stack = task ? (unsigned long *) task->thread.ksp : __r15;
141         else
142                 stack = sp;
143
144         for (i = 0; i < kstack_depth_to_print; i++) {
145                 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
146                         break;
147                 if (i && ((i * sizeof (long) % 32) == 0))
148                         printk("\n       ");
149                 printk(LONG, *stack++);
150         }
151         printk("\n");
152         show_trace(task, sp);
153 }
154
155 static void show_last_breaking_event(struct pt_regs *regs)
156 {
157 #ifdef CONFIG_64BIT
158         printk("Last Breaking-Event-Address:\n");
159         printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
160         print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
161 #endif
162 }
163
164 /*
165  * The architecture-independent dump_stack generator
166  */
167 void dump_stack(void)
168 {
169         printk("CPU: %d %s %s %.*s\n",
170                task_thread_info(current)->cpu, print_tainted(),
171                init_utsname()->release,
172                (int)strcspn(init_utsname()->version, " "),
173                init_utsname()->version);
174         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
175                current->comm, current->pid, current,
176                (void *) current->thread.ksp);
177         show_stack(NULL, NULL);
178 }
179 EXPORT_SYMBOL(dump_stack);
180
181 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
182 {
183         return (regs->psw.mask & bits) / ((~bits + 1) & bits);
184 }
185
186 void show_registers(struct pt_regs *regs)
187 {
188         char *mode;
189
190         mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
191         printk("%s PSW : %p %p",
192                mode, (void *) regs->psw.mask,
193                (void *) regs->psw.addr);
194         print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
195         printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
196                "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
197                mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
198                mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
199                mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
200                mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
201                mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
202 #ifdef CONFIG_64BIT
203         printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS));
204 #endif
205         printk("\n%s GPRS: " FOURLONG, mode,
206                regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
207         printk("           " FOURLONG,
208                regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
209         printk("           " FOURLONG,
210                regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
211         printk("           " FOURLONG,
212                regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
213
214         show_code(regs);
215 }       
216
217 void show_regs(struct pt_regs *regs)
218 {
219         print_modules();
220         printk("CPU: %d %s %s %.*s\n",
221                task_thread_info(current)->cpu, print_tainted(),
222                init_utsname()->release,
223                (int)strcspn(init_utsname()->version, " "),
224                init_utsname()->version);
225         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
226                current->comm, current->pid, current,
227                (void *) current->thread.ksp);
228         show_registers(regs);
229         /* Show stack backtrace if pt_regs is from kernel mode */
230         if (!(regs->psw.mask & PSW_MASK_PSTATE))
231                 show_trace(NULL, (unsigned long *) regs->gprs[15]);
232         show_last_breaking_event(regs);
233 }
234
235 static DEFINE_SPINLOCK(die_lock);
236
237 void die(const char * str, struct pt_regs * regs, long err)
238 {
239         static int die_counter;
240
241         oops_enter();
242         debug_stop_all();
243         console_verbose();
244         spin_lock_irq(&die_lock);
245         bust_spinlocks(1);
246         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
247 #ifdef CONFIG_PREEMPT
248         printk("PREEMPT ");
249 #endif
250 #ifdef CONFIG_SMP
251         printk("SMP ");
252 #endif
253 #ifdef CONFIG_DEBUG_PAGEALLOC
254         printk("DEBUG_PAGEALLOC");
255 #endif
256         printk("\n");
257         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
258         show_regs(regs);
259         bust_spinlocks(0);
260         add_taint(TAINT_DIE);
261         spin_unlock_irq(&die_lock);
262         if (in_interrupt())
263                 panic("Fatal exception in interrupt");
264         if (panic_on_oops)
265                 panic("Fatal exception: panic_on_oops");
266         oops_exit();
267         do_exit(SIGSEGV);
268 }
269
270 static void inline report_user_fault(struct pt_regs *regs, long int_code,
271                                      int signr)
272 {
273         if ((task_pid_nr(current) > 1) && !show_unhandled_signals)
274                 return;
275         if (!unhandled_signal(current, signr))
276                 return;
277         if (!printk_ratelimit())
278                 return;
279         printk("User process fault: interruption code 0x%lX ", int_code);
280         print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN);
281         printk("\n");
282         show_regs(regs);
283 }
284
285 int is_valid_bugaddr(unsigned long addr)
286 {
287         return 1;
288 }
289
290 static inline void __kprobes do_trap(long pgm_int_code, int signr, char *str,
291                                      struct pt_regs *regs, siginfo_t *info)
292 {
293         if (notify_die(DIE_TRAP, str, regs, pgm_int_code,
294                        pgm_int_code, signr) == NOTIFY_STOP)
295                 return;
296
297         if (regs->psw.mask & PSW_MASK_PSTATE) {
298                 struct task_struct *tsk = current;
299
300                 tsk->thread.trap_no = pgm_int_code & 0xffff;
301                 force_sig_info(signr, info, tsk);
302                 report_user_fault(regs, pgm_int_code, signr);
303         } else {
304                 const struct exception_table_entry *fixup;
305                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
306                 if (fixup)
307                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
308                 else {
309                         enum bug_trap_type btt;
310
311                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
312                         if (btt == BUG_TRAP_TYPE_WARN)
313                                 return;
314                         die(str, regs, pgm_int_code);
315                 }
316         }
317 }
318
319 static inline void __user *get_psw_address(struct pt_regs *regs,
320                                            long pgm_int_code)
321 {
322         return (void __user *)
323                 ((regs->psw.addr - (pgm_int_code >> 16)) & PSW_ADDR_INSN);
324 }
325
326 void __kprobes do_per_trap(struct pt_regs *regs)
327 {
328         siginfo_t info;
329
330         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
331                 return;
332         if (!current->ptrace)
333                 return;
334         info.si_signo = SIGTRAP;
335         info.si_errno = 0;
336         info.si_code = TRAP_HWBKPT;
337         info.si_addr = (void *) current->thread.per_event.address;
338         force_sig_info(SIGTRAP, &info, current);
339 }
340
341 static void default_trap_handler(struct pt_regs *regs, long pgm_int_code,
342                                  unsigned long trans_exc_code)
343 {
344         if (regs->psw.mask & PSW_MASK_PSTATE) {
345                 report_user_fault(regs, pgm_int_code, SIGSEGV);
346                 do_exit(SIGSEGV);
347         } else
348                 die("Unknown program exception", regs, pgm_int_code);
349 }
350
351 #define DO_ERROR_INFO(name, signr, sicode, str) \
352 static void name(struct pt_regs *regs, long pgm_int_code, \
353                  unsigned long trans_exc_code) \
354 { \
355         siginfo_t info; \
356         info.si_signo = signr; \
357         info.si_errno = 0; \
358         info.si_code = sicode; \
359         info.si_addr = get_psw_address(regs, pgm_int_code); \
360         do_trap(pgm_int_code, signr, str, regs, &info);     \
361 }
362
363 DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
364               "addressing exception")
365 DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
366               "execute exception")
367 DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
368               "fixpoint divide exception")
369 DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
370               "fixpoint overflow exception")
371 DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
372               "HFP overflow exception")
373 DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
374               "HFP underflow exception")
375 DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
376               "HFP significance exception")
377 DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
378               "HFP divide exception")
379 DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
380               "HFP square root exception")
381 DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
382               "operand exception")
383 DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
384               "privileged operation")
385 DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
386               "special operation exception")
387 DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN,
388               "translation exception")
389
390 static inline void do_fp_trap(struct pt_regs *regs, void __user *location,
391                               int fpc, long pgm_int_code)
392 {
393         siginfo_t si;
394
395         si.si_signo = SIGFPE;
396         si.si_errno = 0;
397         si.si_addr = location;
398         si.si_code = 0;
399         /* FPC[2] is Data Exception Code */
400         if ((fpc & 0x00000300) == 0) {
401                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
402                 if (fpc & 0x8000) /* invalid fp operation */
403                         si.si_code = FPE_FLTINV;
404                 else if (fpc & 0x4000) /* div by 0 */
405                         si.si_code = FPE_FLTDIV;
406                 else if (fpc & 0x2000) /* overflow */
407                         si.si_code = FPE_FLTOVF;
408                 else if (fpc & 0x1000) /* underflow */
409                         si.si_code = FPE_FLTUND;
410                 else if (fpc & 0x0800) /* inexact */
411                         si.si_code = FPE_FLTRES;
412         }
413         do_trap(pgm_int_code, SIGFPE,
414                 "floating point exception", regs, &si);
415 }
416
417 static void __kprobes illegal_op(struct pt_regs *regs, long pgm_int_code,
418                                  unsigned long trans_exc_code)
419 {
420         siginfo_t info;
421         __u8 opcode[6];
422         __u16 __user *location;
423         int signal = 0;
424
425         location = get_psw_address(regs, pgm_int_code);
426
427         if (regs->psw.mask & PSW_MASK_PSTATE) {
428                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
429                         return;
430                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
431                         if (current->ptrace) {
432                                 info.si_signo = SIGTRAP;
433                                 info.si_errno = 0;
434                                 info.si_code = TRAP_BRKPT;
435                                 info.si_addr = location;
436                                 force_sig_info(SIGTRAP, &info, current);
437                         } else
438                                 signal = SIGILL;
439 #ifdef CONFIG_MATHEMU
440                 } else if (opcode[0] == 0xb3) {
441                         if (get_user(*((__u16 *) (opcode+2)), location+1))
442                                 return;
443                         signal = math_emu_b3(opcode, regs);
444                 } else if (opcode[0] == 0xed) {
445                         if (get_user(*((__u32 *) (opcode+2)),
446                                      (__u32 __user *)(location+1)))
447                                 return;
448                         signal = math_emu_ed(opcode, regs);
449                 } else if (*((__u16 *) opcode) == 0xb299) {
450                         if (get_user(*((__u16 *) (opcode+2)), location+1))
451                                 return;
452                         signal = math_emu_srnm(opcode, regs);
453                 } else if (*((__u16 *) opcode) == 0xb29c) {
454                         if (get_user(*((__u16 *) (opcode+2)), location+1))
455                                 return;
456                         signal = math_emu_stfpc(opcode, regs);
457                 } else if (*((__u16 *) opcode) == 0xb29d) {
458                         if (get_user(*((__u16 *) (opcode+2)), location+1))
459                                 return;
460                         signal = math_emu_lfpc(opcode, regs);
461 #endif
462                 } else
463                         signal = SIGILL;
464         } else {
465                 /*
466                  * If we get an illegal op in kernel mode, send it through the
467                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
468                  */
469                 if (notify_die(DIE_BPT, "bpt", regs, pgm_int_code,
470                                3, SIGTRAP) != NOTIFY_STOP)
471                         signal = SIGILL;
472         }
473
474 #ifdef CONFIG_MATHEMU
475         if (signal == SIGFPE)
476                 do_fp_trap(regs, location,
477                            current->thread.fp_regs.fpc, pgm_int_code);
478         else if (signal == SIGSEGV) {
479                 info.si_signo = signal;
480                 info.si_errno = 0;
481                 info.si_code = SEGV_MAPERR;
482                 info.si_addr = (void __user *) location;
483                 do_trap(pgm_int_code, signal,
484                         "user address fault", regs, &info);
485         } else
486 #endif
487         if (signal) {
488                 info.si_signo = signal;
489                 info.si_errno = 0;
490                 info.si_code = ILL_ILLOPC;
491                 info.si_addr = (void __user *) location;
492                 do_trap(pgm_int_code, signal,
493                         "illegal operation", regs, &info);
494         }
495 }
496
497
498 #ifdef CONFIG_MATHEMU
499 void specification_exception(struct pt_regs *regs, long pgm_int_code,
500                              unsigned long trans_exc_code)
501 {
502         __u8 opcode[6];
503         __u16 __user *location = NULL;
504         int signal = 0;
505
506         location = (__u16 __user *) get_psw_address(regs, pgm_int_code);
507
508         if (regs->psw.mask & PSW_MASK_PSTATE) {
509                 get_user(*((__u16 *) opcode), location);
510                 switch (opcode[0]) {
511                 case 0x28: /* LDR Rx,Ry   */
512                         signal = math_emu_ldr(opcode);
513                         break;
514                 case 0x38: /* LER Rx,Ry   */
515                         signal = math_emu_ler(opcode);
516                         break;
517                 case 0x60: /* STD R,D(X,B) */
518                         get_user(*((__u16 *) (opcode+2)), location+1);
519                         signal = math_emu_std(opcode, regs);
520                         break;
521                 case 0x68: /* LD R,D(X,B) */
522                         get_user(*((__u16 *) (opcode+2)), location+1);
523                         signal = math_emu_ld(opcode, regs);
524                         break;
525                 case 0x70: /* STE R,D(X,B) */
526                         get_user(*((__u16 *) (opcode+2)), location+1);
527                         signal = math_emu_ste(opcode, regs);
528                         break;
529                 case 0x78: /* LE R,D(X,B) */
530                         get_user(*((__u16 *) (opcode+2)), location+1);
531                         signal = math_emu_le(opcode, regs);
532                         break;
533                 default:
534                         signal = SIGILL;
535                         break;
536                 }
537         } else
538                 signal = SIGILL;
539
540         if (signal == SIGFPE)
541                 do_fp_trap(regs, location,
542                            current->thread.fp_regs.fpc, pgm_int_code);
543         else if (signal) {
544                 siginfo_t info;
545                 info.si_signo = signal;
546                 info.si_errno = 0;
547                 info.si_code = ILL_ILLOPN;
548                 info.si_addr = location;
549                 do_trap(pgm_int_code, signal,
550                         "specification exception", regs, &info);
551         }
552 }
553 #else
554 DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
555               "specification exception");
556 #endif
557
558 static void data_exception(struct pt_regs *regs, long pgm_int_code,
559                            unsigned long trans_exc_code)
560 {
561         __u16 __user *location;
562         int signal = 0;
563
564         location = get_psw_address(regs, pgm_int_code);
565
566         if (MACHINE_HAS_IEEE)
567                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
568
569 #ifdef CONFIG_MATHEMU
570         else if (regs->psw.mask & PSW_MASK_PSTATE) {
571                 __u8 opcode[6];
572                 get_user(*((__u16 *) opcode), location);
573                 switch (opcode[0]) {
574                 case 0x28: /* LDR Rx,Ry   */
575                         signal = math_emu_ldr(opcode);
576                         break;
577                 case 0x38: /* LER Rx,Ry   */
578                         signal = math_emu_ler(opcode);
579                         break;
580                 case 0x60: /* STD R,D(X,B) */
581                         get_user(*((__u16 *) (opcode+2)), location+1);
582                         signal = math_emu_std(opcode, regs);
583                         break;
584                 case 0x68: /* LD R,D(X,B) */
585                         get_user(*((__u16 *) (opcode+2)), location+1);
586                         signal = math_emu_ld(opcode, regs);
587                         break;
588                 case 0x70: /* STE R,D(X,B) */
589                         get_user(*((__u16 *) (opcode+2)), location+1);
590                         signal = math_emu_ste(opcode, regs);
591                         break;
592                 case 0x78: /* LE R,D(X,B) */
593                         get_user(*((__u16 *) (opcode+2)), location+1);
594                         signal = math_emu_le(opcode, regs);
595                         break;
596                 case 0xb3:
597                         get_user(*((__u16 *) (opcode+2)), location+1);
598                         signal = math_emu_b3(opcode, regs);
599                         break;
600                 case 0xed:
601                         get_user(*((__u32 *) (opcode+2)),
602                                  (__u32 __user *)(location+1));
603                         signal = math_emu_ed(opcode, regs);
604                         break;
605                 case 0xb2:
606                         if (opcode[1] == 0x99) {
607                                 get_user(*((__u16 *) (opcode+2)), location+1);
608                                 signal = math_emu_srnm(opcode, regs);
609                         } else if (opcode[1] == 0x9c) {
610                                 get_user(*((__u16 *) (opcode+2)), location+1);
611                                 signal = math_emu_stfpc(opcode, regs);
612                         } else if (opcode[1] == 0x9d) {
613                                 get_user(*((__u16 *) (opcode+2)), location+1);
614                                 signal = math_emu_lfpc(opcode, regs);
615                         } else
616                                 signal = SIGILL;
617                         break;
618                 default:
619                         signal = SIGILL;
620                         break;
621                 }
622         }
623 #endif 
624         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
625                 signal = SIGFPE;
626         else
627                 signal = SIGILL;
628         if (signal == SIGFPE)
629                 do_fp_trap(regs, location,
630                            current->thread.fp_regs.fpc, pgm_int_code);
631         else if (signal) {
632                 siginfo_t info;
633                 info.si_signo = signal;
634                 info.si_errno = 0;
635                 info.si_code = ILL_ILLOPN;
636                 info.si_addr = location;
637                 do_trap(pgm_int_code, signal, "data exception", regs, &info);
638         }
639 }
640
641 static void space_switch_exception(struct pt_regs *regs, long pgm_int_code,
642                                    unsigned long trans_exc_code)
643 {
644         siginfo_t info;
645
646         /* Set user psw back to home space mode. */
647         if (regs->psw.mask & PSW_MASK_PSTATE)
648                 regs->psw.mask |= PSW_ASC_HOME;
649         /* Send SIGILL. */
650         info.si_signo = SIGILL;
651         info.si_errno = 0;
652         info.si_code = ILL_PRVOPC;
653         info.si_addr = get_psw_address(regs, pgm_int_code);
654         do_trap(pgm_int_code, SIGILL, "space switch event", regs, &info);
655 }
656
657 void __kprobes kernel_stack_overflow(struct pt_regs * regs)
658 {
659         bust_spinlocks(1);
660         printk("Kernel stack overflow.\n");
661         show_regs(regs);
662         bust_spinlocks(0);
663         panic("Corrupt kernel stack, can't continue.");
664 }
665
666 /* init is done in lowcore.S and head.S */
667
668 void __init trap_init(void)
669 {
670         int i;
671
672         for (i = 0; i < 128; i++)
673           pgm_check_table[i] = &default_trap_handler;
674         pgm_check_table[1] = &illegal_op;
675         pgm_check_table[2] = &privileged_op;
676         pgm_check_table[3] = &execute_exception;
677         pgm_check_table[4] = &do_protection_exception;
678         pgm_check_table[5] = &addressing_exception;
679         pgm_check_table[6] = &specification_exception;
680         pgm_check_table[7] = &data_exception;
681         pgm_check_table[8] = &overflow_exception;
682         pgm_check_table[9] = &divide_exception;
683         pgm_check_table[0x0A] = &overflow_exception;
684         pgm_check_table[0x0B] = &divide_exception;
685         pgm_check_table[0x0C] = &hfp_overflow_exception;
686         pgm_check_table[0x0D] = &hfp_underflow_exception;
687         pgm_check_table[0x0E] = &hfp_significance_exception;
688         pgm_check_table[0x0F] = &hfp_divide_exception;
689         pgm_check_table[0x10] = &do_dat_exception;
690         pgm_check_table[0x11] = &do_dat_exception;
691         pgm_check_table[0x12] = &translation_exception;
692         pgm_check_table[0x13] = &special_op_exception;
693 #ifdef CONFIG_64BIT
694         pgm_check_table[0x38] = &do_asce_exception;
695         pgm_check_table[0x39] = &do_dat_exception;
696         pgm_check_table[0x3A] = &do_dat_exception;
697         pgm_check_table[0x3B] = &do_dat_exception;
698 #endif /* CONFIG_64BIT */
699         pgm_check_table[0x15] = &operand_exception;
700         pgm_check_table[0x1C] = &space_switch_exception;
701         pgm_check_table[0x1D] = &hfp_sqrt_exception;
702         /* Enable machine checks early. */
703         local_mcck_enable();
704 }