xref: /openbmc/linux/arch/s390/kernel/traps.c (revision 87c2ce3b)
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/config.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/ptrace.h>
23 #include <linux/timer.h>
24 #include <linux/mm.h>
25 #include <linux/smp.h>
26 #include <linux/smp_lock.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 #include <linux/module.h>
31 #include <linux/kallsyms.h>
32 #include <linux/reboot.h>
33 
34 #include <asm/system.h>
35 #include <asm/uaccess.h>
36 #include <asm/io.h>
37 #include <asm/atomic.h>
38 #include <asm/mathemu.h>
39 #include <asm/cpcmd.h>
40 #include <asm/s390_ext.h>
41 #include <asm/lowcore.h>
42 #include <asm/debug.h>
43 
44 /* Called from entry.S only */
45 extern void handle_per_exception(struct pt_regs *regs);
46 
47 typedef void pgm_check_handler_t(struct pt_regs *, long);
48 pgm_check_handler_t *pgm_check_table[128];
49 
50 #ifdef CONFIG_SYSCTL
51 #ifdef CONFIG_PROCESS_DEBUG
52 int sysctl_userprocess_debug = 1;
53 #else
54 int sysctl_userprocess_debug = 0;
55 #endif
56 #endif
57 
58 extern pgm_check_handler_t do_protection_exception;
59 extern pgm_check_handler_t do_dat_exception;
60 #ifdef CONFIG_PFAULT
61 extern int pfault_init(void);
62 extern void pfault_fini(void);
63 extern void pfault_interrupt(struct pt_regs *regs, __u16 error_code);
64 static ext_int_info_t ext_int_pfault;
65 #endif
66 extern pgm_check_handler_t do_monitor_call;
67 
68 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
69 
70 #ifndef CONFIG_64BIT
71 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
72 static int kstack_depth_to_print = 12;
73 #else /* CONFIG_64BIT */
74 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
75 static int kstack_depth_to_print = 20;
76 #endif /* CONFIG_64BIT */
77 
78 /*
79  * For show_trace we have tree different stack to consider:
80  *   - the panic stack which is used if the kernel stack has overflown
81  *   - the asynchronous interrupt stack (cpu related)
82  *   - the synchronous kernel stack (process related)
83  * The stack trace can start at any of the three stack and can potentially
84  * touch all of them. The order is: panic stack, async stack, sync stack.
85  */
86 static unsigned long
87 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
88 {
89 	struct stack_frame *sf;
90 	struct pt_regs *regs;
91 
92 	while (1) {
93 		sp = sp & PSW_ADDR_INSN;
94 		if (sp < low || sp > high - sizeof(*sf))
95 			return sp;
96 		sf = (struct stack_frame *) sp;
97 		printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
98 		print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
99 		/* Follow the backchain. */
100 		while (1) {
101 			low = sp;
102 			sp = sf->back_chain & PSW_ADDR_INSN;
103 			if (!sp)
104 				break;
105 			if (sp <= low || sp > high - sizeof(*sf))
106 				return sp;
107 			sf = (struct stack_frame *) sp;
108 			printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
109 			print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
110 		}
111 		/* Zero backchain detected, check for interrupt frame. */
112 		sp = (unsigned long) (sf + 1);
113 		if (sp <= low || sp > high - sizeof(*regs))
114 			return sp;
115 		regs = (struct pt_regs *) sp;
116 		printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
117 		print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
118 		low = sp;
119 		sp = regs->gprs[15];
120 	}
121 }
122 
123 void show_trace(struct task_struct *task, unsigned long * stack)
124 {
125 	register unsigned long __r15 asm ("15");
126 	unsigned long sp;
127 
128 	sp = (unsigned long) stack;
129 	if (!sp)
130 		sp = task ? task->thread.ksp : __r15;
131 	printk("Call Trace:\n");
132 #ifdef CONFIG_CHECK_STACK
133 	sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
134 			  S390_lowcore.panic_stack);
135 #endif
136 	sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
137 			  S390_lowcore.async_stack);
138 	if (task)
139 		__show_trace(sp, (unsigned long) task->thread_info,
140 			     (unsigned long) task->thread_info + THREAD_SIZE);
141 	else
142 		__show_trace(sp, S390_lowcore.thread_info,
143 			     S390_lowcore.thread_info + THREAD_SIZE);
144 	printk("\n");
145 }
146 
147 void show_stack(struct task_struct *task, unsigned long *sp)
148 {
149 	register unsigned long * __r15 asm ("15");
150 	unsigned long *stack;
151 	int i;
152 
153 	// debugging aid: "show_stack(NULL);" prints the
154 	// back trace for this cpu.
155 
156 	if (!sp)
157 		sp = task ? (unsigned long *) task->thread.ksp : __r15;
158 
159 	stack = sp;
160 	for (i = 0; i < kstack_depth_to_print; i++) {
161 		if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
162 			break;
163 		if (i && ((i * sizeof (long) % 32) == 0))
164 			printk("\n       ");
165 		printk("%p ", (void *)*stack++);
166 	}
167 	printk("\n");
168 	show_trace(task, sp);
169 }
170 
171 /*
172  * The architecture-independent dump_stack generator
173  */
174 void dump_stack(void)
175 {
176 	show_stack(0, 0);
177 }
178 
179 EXPORT_SYMBOL(dump_stack);
180 
181 void show_registers(struct pt_regs *regs)
182 {
183 	mm_segment_t old_fs;
184 	char *mode;
185 	int i;
186 
187 	mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
188 	printk("%s PSW : %p %p",
189 	       mode, (void *) regs->psw.mask,
190 	       (void *) regs->psw.addr);
191 	print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
192 	printk("%s GPRS: " FOURLONG, mode,
193 	       regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
194 	printk("           " FOURLONG,
195 	       regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
196 	printk("           " FOURLONG,
197 	       regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
198 	printk("           " FOURLONG,
199 	       regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
200 
201 #if 0
202 	/* FIXME: this isn't needed any more but it changes the ksymoops
203 	 * input. To remove or not to remove ... */
204 	save_access_regs(regs->acrs);
205 	printk("%s ACRS: %08x %08x %08x %08x\n", mode,
206 	       regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
207 	printk("           %08x %08x %08x %08x\n",
208 	       regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
209 	printk("           %08x %08x %08x %08x\n",
210 	       regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
211 	printk("           %08x %08x %08x %08x\n",
212 	       regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
213 #endif
214 
215 	/*
216 	 * Print the first 20 byte of the instruction stream at the
217 	 * time of the fault.
218 	 */
219 	old_fs = get_fs();
220 	if (regs->psw.mask & PSW_MASK_PSTATE)
221 		set_fs(USER_DS);
222 	else
223 		set_fs(KERNEL_DS);
224 	printk("%s Code: ", mode);
225 	for (i = 0; i < 20; i++) {
226 		unsigned char c;
227 		if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
228 			printk(" Bad PSW.");
229 			break;
230 		}
231 		printk("%02x ", c);
232 	}
233 	set_fs(old_fs);
234 
235 	printk("\n");
236 }
237 
238 /* This is called from fs/proc/array.c */
239 char *task_show_regs(struct task_struct *task, char *buffer)
240 {
241 	struct pt_regs *regs;
242 
243 	regs = __KSTK_PTREGS(task);
244 	buffer += sprintf(buffer, "task: %p, ksp: %p\n",
245 		       task, (void *)task->thread.ksp);
246 	buffer += sprintf(buffer, "User PSW : %p %p\n",
247 		       (void *) regs->psw.mask, (void *)regs->psw.addr);
248 
249 	buffer += sprintf(buffer, "User GPRS: " FOURLONG,
250 			  regs->gprs[0], regs->gprs[1],
251 			  regs->gprs[2], regs->gprs[3]);
252 	buffer += sprintf(buffer, "           " FOURLONG,
253 			  regs->gprs[4], regs->gprs[5],
254 			  regs->gprs[6], regs->gprs[7]);
255 	buffer += sprintf(buffer, "           " FOURLONG,
256 			  regs->gprs[8], regs->gprs[9],
257 			  regs->gprs[10], regs->gprs[11]);
258 	buffer += sprintf(buffer, "           " FOURLONG,
259 			  regs->gprs[12], regs->gprs[13],
260 			  regs->gprs[14], regs->gprs[15]);
261 	buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
262 			  task->thread.acrs[0], task->thread.acrs[1],
263 			  task->thread.acrs[2], task->thread.acrs[3]);
264 	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
265 			  task->thread.acrs[4], task->thread.acrs[5],
266 			  task->thread.acrs[6], task->thread.acrs[7]);
267 	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
268 			  task->thread.acrs[8], task->thread.acrs[9],
269 			  task->thread.acrs[10], task->thread.acrs[11]);
270 	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",
271 			  task->thread.acrs[12], task->thread.acrs[13],
272 			  task->thread.acrs[14], task->thread.acrs[15]);
273 	return buffer;
274 }
275 
276 DEFINE_SPINLOCK(die_lock);
277 
278 void die(const char * str, struct pt_regs * regs, long err)
279 {
280 	static int die_counter;
281 
282 	debug_stop_all();
283 	console_verbose();
284 	spin_lock_irq(&die_lock);
285 	bust_spinlocks(1);
286 	printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
287         show_regs(regs);
288 	bust_spinlocks(0);
289         spin_unlock_irq(&die_lock);
290 	if (in_interrupt())
291 		panic("Fatal exception in interrupt");
292 	if (panic_on_oops)
293 		panic("Fatal exception: panic_on_oops");
294         do_exit(SIGSEGV);
295 }
296 
297 static void inline
298 report_user_fault(long interruption_code, struct pt_regs *regs)
299 {
300 #if defined(CONFIG_SYSCTL)
301 	if (!sysctl_userprocess_debug)
302 		return;
303 #endif
304 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
305 	printk("User process fault: interruption code 0x%lX\n",
306 	       interruption_code);
307 	show_regs(regs);
308 #endif
309 }
310 
311 static void inline do_trap(long interruption_code, int signr, char *str,
312                            struct pt_regs *regs, siginfo_t *info)
313 {
314 	/*
315 	 * We got all needed information from the lowcore and can
316 	 * now safely switch on interrupts.
317 	 */
318         if (regs->psw.mask & PSW_MASK_PSTATE)
319 		local_irq_enable();
320 
321         if (regs->psw.mask & PSW_MASK_PSTATE) {
322                 struct task_struct *tsk = current;
323 
324                 tsk->thread.trap_no = interruption_code & 0xffff;
325 		force_sig_info(signr, info, tsk);
326 		report_user_fault(interruption_code, regs);
327         } else {
328                 const struct exception_table_entry *fixup;
329                 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
330                 if (fixup)
331                         regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
332                 else
333                         die(str, regs, interruption_code);
334         }
335 }
336 
337 static inline void *get_check_address(struct pt_regs *regs)
338 {
339 	return (void *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
340 }
341 
342 void do_single_step(struct pt_regs *regs)
343 {
344 	if ((current->ptrace & PT_PTRACED) != 0)
345 		force_sig(SIGTRAP, current);
346 }
347 
348 asmlinkage void
349 default_trap_handler(struct pt_regs * regs, long interruption_code)
350 {
351         if (regs->psw.mask & PSW_MASK_PSTATE) {
352 		local_irq_enable();
353 		do_exit(SIGSEGV);
354 		report_user_fault(interruption_code, regs);
355 	} else
356 		die("Unknown program exception", regs, interruption_code);
357 }
358 
359 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
360 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
361 { \
362         siginfo_t info; \
363         info.si_signo = signr; \
364         info.si_errno = 0; \
365         info.si_code = sicode; \
366         info.si_addr = (void *)siaddr; \
367         do_trap(interruption_code, signr, str, regs, &info); \
368 }
369 
370 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
371 	      ILL_ILLADR, get_check_address(regs))
372 DO_ERROR_INFO(SIGILL,  "execute exception", execute_exception,
373 	      ILL_ILLOPN, get_check_address(regs))
374 DO_ERROR_INFO(SIGFPE,  "fixpoint divide exception", divide_exception,
375 	      FPE_INTDIV, get_check_address(regs))
376 DO_ERROR_INFO(SIGFPE,  "fixpoint overflow exception", overflow_exception,
377 	      FPE_INTOVF, get_check_address(regs))
378 DO_ERROR_INFO(SIGFPE,  "HFP overflow exception", hfp_overflow_exception,
379 	      FPE_FLTOVF, get_check_address(regs))
380 DO_ERROR_INFO(SIGFPE,  "HFP underflow exception", hfp_underflow_exception,
381 	      FPE_FLTUND, get_check_address(regs))
382 DO_ERROR_INFO(SIGFPE,  "HFP significance exception", hfp_significance_exception,
383 	      FPE_FLTRES, get_check_address(regs))
384 DO_ERROR_INFO(SIGFPE,  "HFP divide exception", hfp_divide_exception,
385 	      FPE_FLTDIV, get_check_address(regs))
386 DO_ERROR_INFO(SIGFPE,  "HFP square root exception", hfp_sqrt_exception,
387 	      FPE_FLTINV, get_check_address(regs))
388 DO_ERROR_INFO(SIGILL,  "operand exception", operand_exception,
389 	      ILL_ILLOPN, get_check_address(regs))
390 DO_ERROR_INFO(SIGILL,  "privileged operation", privileged_op,
391 	      ILL_PRVOPC, get_check_address(regs))
392 DO_ERROR_INFO(SIGILL,  "special operation exception", special_op_exception,
393 	      ILL_ILLOPN, get_check_address(regs))
394 DO_ERROR_INFO(SIGILL,  "translation exception", translation_exception,
395 	      ILL_ILLOPN, get_check_address(regs))
396 
397 static inline void
398 do_fp_trap(struct pt_regs *regs, void *location,
399            int fpc, long interruption_code)
400 {
401 	siginfo_t si;
402 
403 	si.si_signo = SIGFPE;
404 	si.si_errno = 0;
405 	si.si_addr = location;
406 	si.si_code = 0;
407 	/* FPC[2] is Data Exception Code */
408 	if ((fpc & 0x00000300) == 0) {
409 		/* bits 6 and 7 of DXC are 0 iff IEEE exception */
410 		if (fpc & 0x8000) /* invalid fp operation */
411 			si.si_code = FPE_FLTINV;
412 		else if (fpc & 0x4000) /* div by 0 */
413 			si.si_code = FPE_FLTDIV;
414 		else if (fpc & 0x2000) /* overflow */
415 			si.si_code = FPE_FLTOVF;
416 		else if (fpc & 0x1000) /* underflow */
417 			si.si_code = FPE_FLTUND;
418 		else if (fpc & 0x0800) /* inexact */
419 			si.si_code = FPE_FLTRES;
420 	}
421 	current->thread.ieee_instruction_pointer = (addr_t) location;
422 	do_trap(interruption_code, SIGFPE,
423 		"floating point exception", regs, &si);
424 }
425 
426 asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
427 {
428 	siginfo_t info;
429         __u8 opcode[6];
430 	__u16 *location;
431 	int signal = 0;
432 
433 	location = (__u16 *) get_check_address(regs);
434 
435 	/*
436 	 * We got all needed information from the lowcore and can
437 	 * now safely switch on interrupts.
438 	 */
439 	if (regs->psw.mask & PSW_MASK_PSTATE)
440 		local_irq_enable();
441 
442 	if (regs->psw.mask & PSW_MASK_PSTATE) {
443 		get_user(*((__u16 *) opcode), (__u16 __user *) location);
444 		if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
445 			if (current->ptrace & PT_PTRACED)
446 				force_sig(SIGTRAP, current);
447 			else
448 				signal = SIGILL;
449 #ifdef CONFIG_MATHEMU
450 		} else if (opcode[0] == 0xb3) {
451 			get_user(*((__u16 *) (opcode+2)), location+1);
452 			signal = math_emu_b3(opcode, regs);
453                 } else if (opcode[0] == 0xed) {
454 			get_user(*((__u32 *) (opcode+2)),
455 				 (__u32 *)(location+1));
456 			signal = math_emu_ed(opcode, regs);
457 		} else if (*((__u16 *) opcode) == 0xb299) {
458 			get_user(*((__u16 *) (opcode+2)), location+1);
459 			signal = math_emu_srnm(opcode, regs);
460 		} else if (*((__u16 *) opcode) == 0xb29c) {
461 			get_user(*((__u16 *) (opcode+2)), location+1);
462 			signal = math_emu_stfpc(opcode, regs);
463 		} else if (*((__u16 *) opcode) == 0xb29d) {
464 			get_user(*((__u16 *) (opcode+2)), location+1);
465 			signal = math_emu_lfpc(opcode, regs);
466 #endif
467 		} else
468 			signal = SIGILL;
469 	} else
470 		signal = SIGILL;
471 
472 #ifdef CONFIG_MATHEMU
473         if (signal == SIGFPE)
474 		do_fp_trap(regs, location,
475                            current->thread.fp_regs.fpc, interruption_code);
476         else if (signal == SIGSEGV) {
477 		info.si_signo = signal;
478 		info.si_errno = 0;
479 		info.si_code = SEGV_MAPERR;
480 		info.si_addr = (void *) location;
481 		do_trap(interruption_code, signal,
482 			"user address fault", regs, &info);
483 	} else
484 #endif
485         if (signal) {
486 		info.si_signo = signal;
487 		info.si_errno = 0;
488 		info.si_code = ILL_ILLOPC;
489 		info.si_addr = (void *) location;
490 		do_trap(interruption_code, signal,
491 			"illegal operation", regs, &info);
492 	}
493 }
494 
495 
496 #ifdef CONFIG_MATHEMU
497 asmlinkage void
498 specification_exception(struct pt_regs * regs, long interruption_code)
499 {
500         __u8 opcode[6];
501 	__u16 *location = NULL;
502 	int signal = 0;
503 
504 	location = (__u16 *) get_check_address(regs);
505 
506 	/*
507 	 * We got all needed information from the lowcore and can
508 	 * now safely switch on interrupts.
509 	 */
510         if (regs->psw.mask & PSW_MASK_PSTATE)
511 		local_irq_enable();
512 
513         if (regs->psw.mask & PSW_MASK_PSTATE) {
514 		get_user(*((__u16 *) opcode), location);
515 		switch (opcode[0]) {
516 		case 0x28: /* LDR Rx,Ry   */
517 			signal = math_emu_ldr(opcode);
518 			break;
519 		case 0x38: /* LER Rx,Ry   */
520 			signal = math_emu_ler(opcode);
521 			break;
522 		case 0x60: /* STD R,D(X,B) */
523 			get_user(*((__u16 *) (opcode+2)), location+1);
524 			signal = math_emu_std(opcode, regs);
525 			break;
526 		case 0x68: /* LD R,D(X,B) */
527 			get_user(*((__u16 *) (opcode+2)), location+1);
528 			signal = math_emu_ld(opcode, regs);
529 			break;
530 		case 0x70: /* STE R,D(X,B) */
531 			get_user(*((__u16 *) (opcode+2)), location+1);
532 			signal = math_emu_ste(opcode, regs);
533 			break;
534 		case 0x78: /* LE R,D(X,B) */
535 			get_user(*((__u16 *) (opcode+2)), location+1);
536 			signal = math_emu_le(opcode, regs);
537 			break;
538 		default:
539 			signal = SIGILL;
540 			break;
541                 }
542         } else
543 		signal = SIGILL;
544 
545         if (signal == SIGFPE)
546 		do_fp_trap(regs, location,
547                            current->thread.fp_regs.fpc, interruption_code);
548         else if (signal) {
549 		siginfo_t info;
550 		info.si_signo = signal;
551 		info.si_errno = 0;
552 		info.si_code = ILL_ILLOPN;
553 		info.si_addr = location;
554 		do_trap(interruption_code, signal,
555 			"specification exception", regs, &info);
556 	}
557 }
558 #else
559 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
560 	      ILL_ILLOPN, get_check_address(regs));
561 #endif
562 
563 asmlinkage void data_exception(struct pt_regs * regs, long interruption_code)
564 {
565 	__u16 *location;
566 	int signal = 0;
567 
568 	location = (__u16 *) get_check_address(regs);
569 
570 	/*
571 	 * We got all needed information from the lowcore and can
572 	 * now safely switch on interrupts.
573 	 */
574 	if (regs->psw.mask & PSW_MASK_PSTATE)
575 		local_irq_enable();
576 
577 	if (MACHINE_HAS_IEEE)
578 		__asm__ volatile ("stfpc %0\n\t"
579 				  : "=m" (current->thread.fp_regs.fpc));
580 
581 #ifdef CONFIG_MATHEMU
582         else if (regs->psw.mask & PSW_MASK_PSTATE) {
583         	__u8 opcode[6];
584 		get_user(*((__u16 *) opcode), location);
585 		switch (opcode[0]) {
586 		case 0x28: /* LDR Rx,Ry   */
587 			signal = math_emu_ldr(opcode);
588 			break;
589 		case 0x38: /* LER Rx,Ry   */
590 			signal = math_emu_ler(opcode);
591 			break;
592 		case 0x60: /* STD R,D(X,B) */
593 			get_user(*((__u16 *) (opcode+2)), location+1);
594 			signal = math_emu_std(opcode, regs);
595 			break;
596 		case 0x68: /* LD R,D(X,B) */
597 			get_user(*((__u16 *) (opcode+2)), location+1);
598 			signal = math_emu_ld(opcode, regs);
599 			break;
600 		case 0x70: /* STE R,D(X,B) */
601 			get_user(*((__u16 *) (opcode+2)), location+1);
602 			signal = math_emu_ste(opcode, regs);
603 			break;
604 		case 0x78: /* LE R,D(X,B) */
605 			get_user(*((__u16 *) (opcode+2)), location+1);
606 			signal = math_emu_le(opcode, regs);
607 			break;
608 		case 0xb3:
609 			get_user(*((__u16 *) (opcode+2)), location+1);
610 			signal = math_emu_b3(opcode, regs);
611 			break;
612                 case 0xed:
613 			get_user(*((__u32 *) (opcode+2)),
614 				 (__u32 *)(location+1));
615 			signal = math_emu_ed(opcode, regs);
616 			break;
617 	        case 0xb2:
618 			if (opcode[1] == 0x99) {
619 				get_user(*((__u16 *) (opcode+2)), location+1);
620 				signal = math_emu_srnm(opcode, regs);
621 			} else if (opcode[1] == 0x9c) {
622 				get_user(*((__u16 *) (opcode+2)), location+1);
623 				signal = math_emu_stfpc(opcode, regs);
624 			} else if (opcode[1] == 0x9d) {
625 				get_user(*((__u16 *) (opcode+2)), location+1);
626 				signal = math_emu_lfpc(opcode, regs);
627 			} else
628 				signal = SIGILL;
629 			break;
630 		default:
631 			signal = SIGILL;
632 			break;
633                 }
634         }
635 #endif
636 	if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
637 		signal = SIGFPE;
638 	else
639 		signal = SIGILL;
640         if (signal == SIGFPE)
641 		do_fp_trap(regs, location,
642                            current->thread.fp_regs.fpc, interruption_code);
643         else if (signal) {
644 		siginfo_t info;
645 		info.si_signo = signal;
646 		info.si_errno = 0;
647 		info.si_code = ILL_ILLOPN;
648 		info.si_addr = location;
649 		do_trap(interruption_code, signal,
650 			"data exception", regs, &info);
651 	}
652 }
653 
654 asmlinkage void space_switch_exception(struct pt_regs * regs, long int_code)
655 {
656         siginfo_t info;
657 
658 	/* Set user psw back to home space mode. */
659 	if (regs->psw.mask & PSW_MASK_PSTATE)
660 		regs->psw.mask |= PSW_ASC_HOME;
661 	/* Send SIGILL. */
662         info.si_signo = SIGILL;
663         info.si_errno = 0;
664         info.si_code = ILL_PRVOPC;
665         info.si_addr = get_check_address(regs);
666         do_trap(int_code, SIGILL, "space switch event", regs, &info);
667 }
668 
669 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
670 {
671 	bust_spinlocks(1);
672 	printk("Kernel stack overflow.\n");
673 	show_regs(regs);
674 	bust_spinlocks(0);
675 	panic("Corrupt kernel stack, can't continue.");
676 }
677 
678 /* init is done in lowcore.S and head.S */
679 
680 void __init trap_init(void)
681 {
682         int i;
683 
684         for (i = 0; i < 128; i++)
685           pgm_check_table[i] = &default_trap_handler;
686         pgm_check_table[1] = &illegal_op;
687         pgm_check_table[2] = &privileged_op;
688         pgm_check_table[3] = &execute_exception;
689         pgm_check_table[4] = &do_protection_exception;
690         pgm_check_table[5] = &addressing_exception;
691         pgm_check_table[6] = &specification_exception;
692         pgm_check_table[7] = &data_exception;
693         pgm_check_table[8] = &overflow_exception;
694         pgm_check_table[9] = &divide_exception;
695         pgm_check_table[0x0A] = &overflow_exception;
696         pgm_check_table[0x0B] = &divide_exception;
697         pgm_check_table[0x0C] = &hfp_overflow_exception;
698         pgm_check_table[0x0D] = &hfp_underflow_exception;
699         pgm_check_table[0x0E] = &hfp_significance_exception;
700         pgm_check_table[0x0F] = &hfp_divide_exception;
701         pgm_check_table[0x10] = &do_dat_exception;
702         pgm_check_table[0x11] = &do_dat_exception;
703         pgm_check_table[0x12] = &translation_exception;
704         pgm_check_table[0x13] = &special_op_exception;
705 #ifdef CONFIG_64BIT
706         pgm_check_table[0x38] = &do_dat_exception;
707 	pgm_check_table[0x39] = &do_dat_exception;
708 	pgm_check_table[0x3A] = &do_dat_exception;
709         pgm_check_table[0x3B] = &do_dat_exception;
710 #endif /* CONFIG_64BIT */
711         pgm_check_table[0x15] = &operand_exception;
712         pgm_check_table[0x1C] = &space_switch_exception;
713         pgm_check_table[0x1D] = &hfp_sqrt_exception;
714 	pgm_check_table[0x40] = &do_monitor_call;
715 
716 	if (MACHINE_IS_VM) {
717 #ifdef CONFIG_PFAULT
718 		/*
719 		 * Try to get pfault pseudo page faults going.
720 		 */
721 		if (register_early_external_interrupt(0x2603, pfault_interrupt,
722 						      &ext_int_pfault) != 0)
723 			panic("Couldn't request external interrupt 0x2603");
724 
725 		if (pfault_init() == 0)
726 			return;
727 
728 		/* Tough luck, no pfault. */
729 		unregister_early_external_interrupt(0x2603, pfault_interrupt,
730 						    &ext_int_pfault);
731 #endif
732 	}
733 }
734