Merge branch 'linus' into x86/pebs
[linux-2.6] / 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 static 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 static void show_last_breaking_event(struct pt_regs *regs)
165 {
166 #ifdef CONFIG_64BIT
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 #endif
171 }
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 void show_regs(struct pt_regs *regs)
227 {
228         print_modules();
229         printk("CPU: %d %s %s %.*s\n",
230                task_thread_info(current)->cpu, print_tainted(),
231                init_utsname()->release,
232                (int)strcspn(init_utsname()->version, " "),
233                init_utsname()->version);
234         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
235                current->comm, current->pid, current,
236                (void *) current->thread.ksp);
237         show_registers(regs);
238         /* Show stack backtrace if pt_regs is from kernel mode */
239         if (!(regs->psw.mask & PSW_MASK_PSTATE))
240                 show_trace(NULL, (unsigned long *) regs->gprs[15]);
241         show_last_breaking_event(regs);
242 }
243
244 /* This is called from fs/proc/array.c */
245 void task_show_regs(struct seq_file *m, struct task_struct *task)
246 {
247         struct pt_regs *regs;
248
249         regs = task_pt_regs(task);
250         seq_printf(m, "task: %p, ksp: %p\n",
251                        task, (void *)task->thread.ksp);
252         seq_printf(m, "User PSW : %p %p\n",
253                        (void *) regs->psw.mask, (void *)regs->psw.addr);
254
255         seq_printf(m, "User GPRS: " FOURLONG,
256                           regs->gprs[0], regs->gprs[1],
257                           regs->gprs[2], regs->gprs[3]);
258         seq_printf(m, "           " FOURLONG,
259                           regs->gprs[4], regs->gprs[5],
260                           regs->gprs[6], regs->gprs[7]);
261         seq_printf(m, "           " FOURLONG,
262                           regs->gprs[8], regs->gprs[9],
263                           regs->gprs[10], regs->gprs[11]);
264         seq_printf(m, "           " FOURLONG,
265                           regs->gprs[12], regs->gprs[13],
266                           regs->gprs[14], regs->gprs[15]);
267         seq_printf(m, "User ACRS: %08x %08x %08x %08x\n",
268                           task->thread.acrs[0], task->thread.acrs[1],
269                           task->thread.acrs[2], task->thread.acrs[3]);
270         seq_printf(m, "           %08x %08x %08x %08x\n",
271                           task->thread.acrs[4], task->thread.acrs[5],
272                           task->thread.acrs[6], task->thread.acrs[7]);
273         seq_printf(m, "           %08x %08x %08x %08x\n",
274                           task->thread.acrs[8], task->thread.acrs[9],
275                           task->thread.acrs[10], task->thread.acrs[11]);
276         seq_printf(m, "           %08x %08x %08x %08x\n",
277                           task->thread.acrs[12], task->thread.acrs[13],
278                           task->thread.acrs[14], task->thread.acrs[15]);
279 }
280
281 static DEFINE_SPINLOCK(die_lock);
282
283 void die(const char * str, struct pt_regs * regs, long err)
284 {
285         static int die_counter;
286
287         oops_enter();
288         debug_stop_all();
289         console_verbose();
290         spin_lock_irq(&die_lock);
291         bust_spinlocks(1);
292         printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
293 #ifdef CONFIG_PREEMPT
294         printk("PREEMPT ");
295 #endif
296 #ifdef CONFIG_SMP
297         printk("SMP ");
298 #endif
299 #ifdef CONFIG_DEBUG_PAGEALLOC
300         printk("DEBUG_PAGEALLOC");
301 #endif
302         printk("\n");
303         notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
304         show_regs(regs);
305         bust_spinlocks(0);
306         add_taint(TAINT_DIE);
307         spin_unlock_irq(&die_lock);
308         if (in_interrupt())
309                 panic("Fatal exception in interrupt");
310         if (panic_on_oops)
311                 panic("Fatal exception: panic_on_oops");
312         oops_exit();
313         do_exit(SIGSEGV);
314 }
315
316 static void inline
317 report_user_fault(long interruption_code, struct pt_regs *regs)
318 {
319 #if defined(CONFIG_SYSCTL)
320         if (!sysctl_userprocess_debug)
321                 return;
322 #endif
323 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
324         printk("User process fault: interruption code 0x%lX\n",
325                interruption_code);
326         show_regs(regs);
327 #endif
328 }
329
330 int is_valid_bugaddr(unsigned long addr)
331 {
332         return 1;
333 }
334
335 static void __kprobes inline do_trap(long interruption_code, int signr,
336                                         char *str, struct pt_regs *regs,
337                                         siginfo_t *info)
338 {
339         /*
340          * We got all needed information from the lowcore and can
341          * now safely switch on interrupts.
342          */
343         if (regs->psw.mask & PSW_MASK_PSTATE)
344                 local_irq_enable();
345
346         if (notify_die(DIE_TRAP, str, regs, interruption_code,
347                                 interruption_code, signr) == NOTIFY_STOP)
348                 return;
349
350         if (regs->psw.mask & PSW_MASK_PSTATE) {
351                 struct task_struct *tsk = current;
352
353                 tsk->thread.trap_no = interruption_code & 0xffff;
354                 force_sig_info(signr, info, tsk);
355                 report_user_fault(interruption_code, regs);
356         } else {
357                 const struct exception_table_entry *fixup;
358                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
359                 if (fixup)
360                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
361                 else {
362                         enum bug_trap_type btt;
363
364                         btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
365                         if (btt == BUG_TRAP_TYPE_WARN)
366                                 return;
367                         die(str, regs, interruption_code);
368                 }
369         }
370 }
371
372 static inline void __user *get_check_address(struct pt_regs *regs)
373 {
374         return (void __user *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
375 }
376
377 void __kprobes do_single_step(struct pt_regs *regs)
378 {
379         if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0,
380                                         SIGTRAP) == NOTIFY_STOP){
381                 return;
382         }
383         if ((current->ptrace & PT_PTRACED) != 0)
384                 force_sig(SIGTRAP, current);
385 }
386
387 static void default_trap_handler(struct pt_regs * regs, long interruption_code)
388 {
389         if (regs->psw.mask & PSW_MASK_PSTATE) {
390                 local_irq_enable();
391                 do_exit(SIGSEGV);
392                 report_user_fault(interruption_code, regs);
393         } else
394                 die("Unknown program exception", regs, interruption_code);
395 }
396
397 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
398 static void name(struct pt_regs * regs, long interruption_code) \
399 { \
400         siginfo_t info; \
401         info.si_signo = signr; \
402         info.si_errno = 0; \
403         info.si_code = sicode; \
404         info.si_addr = siaddr; \
405         do_trap(interruption_code, signr, str, regs, &info); \
406 }
407
408 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
409               ILL_ILLADR, get_check_address(regs))
410 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
411               ILL_ILLOPN, get_check_address(regs))
412 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
413               FPE_INTDIV, get_check_address(regs))
414 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
415               FPE_INTOVF, get_check_address(regs))
416 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
417               FPE_FLTOVF, get_check_address(regs))
418 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
419               FPE_FLTUND, get_check_address(regs))
420 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
421               FPE_FLTRES, get_check_address(regs))
422 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
423               FPE_FLTDIV, get_check_address(regs))
424 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
425               FPE_FLTINV, get_check_address(regs))
426 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
427               ILL_ILLOPN, get_check_address(regs))
428 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
429               ILL_PRVOPC, get_check_address(regs))
430 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
431               ILL_ILLOPN, get_check_address(regs))
432 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
433               ILL_ILLOPN, get_check_address(regs))
434
435 static inline void
436 do_fp_trap(struct pt_regs *regs, void __user *location,
437            int fpc, long interruption_code)
438 {
439         siginfo_t si;
440
441         si.si_signo = SIGFPE;
442         si.si_errno = 0;
443         si.si_addr = location;
444         si.si_code = 0;
445         /* FPC[2] is Data Exception Code */
446         if ((fpc & 0x00000300) == 0) {
447                 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
448                 if (fpc & 0x8000) /* invalid fp operation */
449                         si.si_code = FPE_FLTINV;
450                 else if (fpc & 0x4000) /* div by 0 */
451                         si.si_code = FPE_FLTDIV;
452                 else if (fpc & 0x2000) /* overflow */
453                         si.si_code = FPE_FLTOVF;
454                 else if (fpc & 0x1000) /* underflow */
455                         si.si_code = FPE_FLTUND;
456                 else if (fpc & 0x0800) /* inexact */
457                         si.si_code = FPE_FLTRES;
458         }
459         current->thread.ieee_instruction_pointer = (addr_t) location;
460         do_trap(interruption_code, SIGFPE,
461                 "floating point exception", regs, &si);
462 }
463
464 static void illegal_op(struct pt_regs * regs, long interruption_code)
465 {
466         siginfo_t info;
467         __u8 opcode[6];
468         __u16 __user *location;
469         int signal = 0;
470
471         location = get_check_address(regs);
472
473         /*
474          * We got all needed information from the lowcore and can
475          * now safely switch on interrupts.
476          */
477         if (regs->psw.mask & PSW_MASK_PSTATE)
478                 local_irq_enable();
479
480         if (regs->psw.mask & PSW_MASK_PSTATE) {
481                 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
482                         return;
483                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
484                         if (current->ptrace & PT_PTRACED)
485                                 force_sig(SIGTRAP, current);
486                         else
487                                 signal = SIGILL;
488 #ifdef CONFIG_MATHEMU
489                 } else if (opcode[0] == 0xb3) {
490                         if (get_user(*((__u16 *) (opcode+2)), location+1))
491                                 return;
492                         signal = math_emu_b3(opcode, regs);
493                 } else if (opcode[0] == 0xed) {
494                         if (get_user(*((__u32 *) (opcode+2)),
495                                      (__u32 __user *)(location+1)))
496                                 return;
497                         signal = math_emu_ed(opcode, regs);
498                 } else if (*((__u16 *) opcode) == 0xb299) {
499                         if (get_user(*((__u16 *) (opcode+2)), location+1))
500                                 return;
501                         signal = math_emu_srnm(opcode, regs);
502                 } else if (*((__u16 *) opcode) == 0xb29c) {
503                         if (get_user(*((__u16 *) (opcode+2)), location+1))
504                                 return;
505                         signal = math_emu_stfpc(opcode, regs);
506                 } else if (*((__u16 *) opcode) == 0xb29d) {
507                         if (get_user(*((__u16 *) (opcode+2)), location+1))
508                                 return;
509                         signal = math_emu_lfpc(opcode, regs);
510 #endif
511                 } else
512                         signal = SIGILL;
513         } else {
514                 /*
515                  * If we get an illegal op in kernel mode, send it through the
516                  * kprobes notifier. If kprobes doesn't pick it up, SIGILL
517                  */
518                 if (notify_die(DIE_BPT, "bpt", regs, interruption_code,
519                                3, SIGTRAP) != NOTIFY_STOP)
520                         signal = SIGILL;
521         }
522
523 #ifdef CONFIG_MATHEMU
524         if (signal == SIGFPE)
525                 do_fp_trap(regs, location,
526                            current->thread.fp_regs.fpc, interruption_code);
527         else if (signal == SIGSEGV) {
528                 info.si_signo = signal;
529                 info.si_errno = 0;
530                 info.si_code = SEGV_MAPERR;
531                 info.si_addr = (void __user *) location;
532                 do_trap(interruption_code, signal,
533                         "user address fault", regs, &info);
534         } else
535 #endif
536         if (signal) {
537                 info.si_signo = signal;
538                 info.si_errno = 0;
539                 info.si_code = ILL_ILLOPC;
540                 info.si_addr = (void __user *) location;
541                 do_trap(interruption_code, signal,
542                         "illegal operation", regs, &info);
543         }
544 }
545
546
547 #ifdef CONFIG_MATHEMU
548 asmlinkage void 
549 specification_exception(struct pt_regs * regs, long interruption_code)
550 {
551         __u8 opcode[6];
552         __u16 __user *location = NULL;
553         int signal = 0;
554
555         location = (__u16 __user *) get_check_address(regs);
556
557         /*
558          * We got all needed information from the lowcore and can
559          * now safely switch on interrupts.
560          */
561         if (regs->psw.mask & PSW_MASK_PSTATE)
562                 local_irq_enable();
563
564         if (regs->psw.mask & PSW_MASK_PSTATE) {
565                 get_user(*((__u16 *) opcode), location);
566                 switch (opcode[0]) {
567                 case 0x28: /* LDR Rx,Ry   */
568                         signal = math_emu_ldr(opcode);
569                         break;
570                 case 0x38: /* LER Rx,Ry   */
571                         signal = math_emu_ler(opcode);
572                         break;
573                 case 0x60: /* STD R,D(X,B) */
574                         get_user(*((__u16 *) (opcode+2)), location+1);
575                         signal = math_emu_std(opcode, regs);
576                         break;
577                 case 0x68: /* LD R,D(X,B) */
578                         get_user(*((__u16 *) (opcode+2)), location+1);
579                         signal = math_emu_ld(opcode, regs);
580                         break;
581                 case 0x70: /* STE R,D(X,B) */
582                         get_user(*((__u16 *) (opcode+2)), location+1);
583                         signal = math_emu_ste(opcode, regs);
584                         break;
585                 case 0x78: /* LE R,D(X,B) */
586                         get_user(*((__u16 *) (opcode+2)), location+1);
587                         signal = math_emu_le(opcode, regs);
588                         break;
589                 default:
590                         signal = SIGILL;
591                         break;
592                 }
593         } else
594                 signal = SIGILL;
595
596         if (signal == SIGFPE)
597                 do_fp_trap(regs, location,
598                            current->thread.fp_regs.fpc, interruption_code);
599         else if (signal) {
600                 siginfo_t info;
601                 info.si_signo = signal;
602                 info.si_errno = 0;
603                 info.si_code = ILL_ILLOPN;
604                 info.si_addr = location;
605                 do_trap(interruption_code, signal, 
606                         "specification exception", regs, &info);
607         }
608 }
609 #else
610 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
611               ILL_ILLOPN, get_check_address(regs));
612 #endif
613
614 static void data_exception(struct pt_regs * regs, long interruption_code)
615 {
616         __u16 __user *location;
617         int signal = 0;
618
619         location = get_check_address(regs);
620
621         /*
622          * We got all needed information from the lowcore and can
623          * now safely switch on interrupts.
624          */
625         if (regs->psw.mask & PSW_MASK_PSTATE)
626                 local_irq_enable();
627
628         if (MACHINE_HAS_IEEE)
629                 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
630
631 #ifdef CONFIG_MATHEMU
632         else if (regs->psw.mask & PSW_MASK_PSTATE) {
633                 __u8 opcode[6];
634                 get_user(*((__u16 *) opcode), location);
635                 switch (opcode[0]) {
636                 case 0x28: /* LDR Rx,Ry   */
637                         signal = math_emu_ldr(opcode);
638                         break;
639                 case 0x38: /* LER Rx,Ry   */
640                         signal = math_emu_ler(opcode);
641                         break;
642                 case 0x60: /* STD R,D(X,B) */
643                         get_user(*((__u16 *) (opcode+2)), location+1);
644                         signal = math_emu_std(opcode, regs);
645                         break;
646                 case 0x68: /* LD R,D(X,B) */
647                         get_user(*((__u16 *) (opcode+2)), location+1);
648                         signal = math_emu_ld(opcode, regs);
649                         break;
650                 case 0x70: /* STE R,D(X,B) */
651                         get_user(*((__u16 *) (opcode+2)), location+1);
652                         signal = math_emu_ste(opcode, regs);
653                         break;
654                 case 0x78: /* LE R,D(X,B) */
655                         get_user(*((__u16 *) (opcode+2)), location+1);
656                         signal = math_emu_le(opcode, regs);
657                         break;
658                 case 0xb3:
659                         get_user(*((__u16 *) (opcode+2)), location+1);
660                         signal = math_emu_b3(opcode, regs);
661                         break;
662                 case 0xed:
663                         get_user(*((__u32 *) (opcode+2)),
664                                  (__u32 __user *)(location+1));
665                         signal = math_emu_ed(opcode, regs);
666                         break;
667                 case 0xb2:
668                         if (opcode[1] == 0x99) {
669                                 get_user(*((__u16 *) (opcode+2)), location+1);
670                                 signal = math_emu_srnm(opcode, regs);
671                         } else if (opcode[1] == 0x9c) {
672                                 get_user(*((__u16 *) (opcode+2)), location+1);
673                                 signal = math_emu_stfpc(opcode, regs);
674                         } else if (opcode[1] == 0x9d) {
675                                 get_user(*((__u16 *) (opcode+2)), location+1);
676                                 signal = math_emu_lfpc(opcode, regs);
677                         } else
678                                 signal = SIGILL;
679                         break;
680                 default:
681                         signal = SIGILL;
682                         break;
683                 }
684         }
685 #endif 
686         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
687                 signal = SIGFPE;
688         else
689                 signal = SIGILL;
690         if (signal == SIGFPE)
691                 do_fp_trap(regs, location,
692                            current->thread.fp_regs.fpc, interruption_code);
693         else if (signal) {
694                 siginfo_t info;
695                 info.si_signo = signal;
696                 info.si_errno = 0;
697                 info.si_code = ILL_ILLOPN;
698                 info.si_addr = location;
699                 do_trap(interruption_code, signal, 
700                         "data exception", regs, &info);
701         }
702 }
703
704 static void space_switch_exception(struct pt_regs * regs, long int_code)
705 {
706         siginfo_t info;
707
708         /* Set user psw back to home space mode. */
709         if (regs->psw.mask & PSW_MASK_PSTATE)
710                 regs->psw.mask |= PSW_ASC_HOME;
711         /* Send SIGILL. */
712         info.si_signo = SIGILL;
713         info.si_errno = 0;
714         info.si_code = ILL_PRVOPC;
715         info.si_addr = get_check_address(regs);
716         do_trap(int_code, SIGILL, "space switch event", regs, &info);
717 }
718
719 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
720 {
721         bust_spinlocks(1);
722         printk("Kernel stack overflow.\n");
723         show_regs(regs);
724         bust_spinlocks(0);
725         panic("Corrupt kernel stack, can't continue.");
726 }
727
728 /* init is done in lowcore.S and head.S */
729
730 void __init trap_init(void)
731 {
732         int i;
733
734         for (i = 0; i < 128; i++)
735           pgm_check_table[i] = &default_trap_handler;
736         pgm_check_table[1] = &illegal_op;
737         pgm_check_table[2] = &privileged_op;
738         pgm_check_table[3] = &execute_exception;
739         pgm_check_table[4] = &do_protection_exception;
740         pgm_check_table[5] = &addressing_exception;
741         pgm_check_table[6] = &specification_exception;
742         pgm_check_table[7] = &data_exception;
743         pgm_check_table[8] = &overflow_exception;
744         pgm_check_table[9] = &divide_exception;
745         pgm_check_table[0x0A] = &overflow_exception;
746         pgm_check_table[0x0B] = &divide_exception;
747         pgm_check_table[0x0C] = &hfp_overflow_exception;
748         pgm_check_table[0x0D] = &hfp_underflow_exception;
749         pgm_check_table[0x0E] = &hfp_significance_exception;
750         pgm_check_table[0x0F] = &hfp_divide_exception;
751         pgm_check_table[0x10] = &do_dat_exception;
752         pgm_check_table[0x11] = &do_dat_exception;
753         pgm_check_table[0x12] = &translation_exception;
754         pgm_check_table[0x13] = &special_op_exception;
755 #ifdef CONFIG_64BIT
756         pgm_check_table[0x38] = &do_asce_exception;
757         pgm_check_table[0x39] = &do_dat_exception;
758         pgm_check_table[0x3A] = &do_dat_exception;
759         pgm_check_table[0x3B] = &do_dat_exception;
760 #endif /* CONFIG_64BIT */
761         pgm_check_table[0x15] = &operand_exception;
762         pgm_check_table[0x1C] = &space_switch_exception;
763         pgm_check_table[0x1D] = &hfp_sqrt_exception;
764         pfault_irq_init();
765 }