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/uaccess.h>
37 #include <asm/io.h>
38 #include <linux/atomic.h>
39 #include <asm/mathemu.h>
40 #include <asm/cpcmd.h>
41 #include <asm/lowcore.h>
42 #include <asm/debug.h>
43 #include <asm/ipl.h>
44 #include "entry.h"
45
46 void (*pgm_check_table[128])(struct pt_regs *regs);
47
48 int show_unhandled_signals = 1;
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
__show_trace(unsigned long sp,unsigned long low,unsigned long high)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
show_trace(struct task_struct * task,unsigned long * stack)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
show_stack(struct task_struct * task,unsigned long * sp)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 * sizeof(long) % 32) == 0)
148 printk("%s ", i == 0 ? "" : "\n");
149 printk(LONG, *stack++);
150 }
151 printk("\n");
152 show_trace(task, sp);
153 }
154
show_last_breaking_event(struct pt_regs * regs)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 */
dump_stack(void)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
mask_bits(struct pt_regs * regs,unsigned long bits)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
show_registers(struct pt_regs * regs)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_MASK_EA | PSW_MASK_BA));
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
show_regs(struct pt_regs * regs)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
die(struct pt_regs * regs,const char * str)237 void die(struct pt_regs *regs, const char *str)
238 {
239 static int die_counter;
240
241 oops_enter();
242 lgr_info_log();
243 debug_stop_all();
244 console_verbose();
245 spin_lock_irq(&die_lock);
246 bust_spinlocks(1);
247 printk("%s: %04x [#%d] ", str, regs->int_code & 0xffff, ++die_counter);
248 #ifdef CONFIG_PREEMPT
249 printk("PREEMPT ");
250 #endif
251 #ifdef CONFIG_SMP
252 printk("SMP ");
253 #endif
254 #ifdef CONFIG_DEBUG_PAGEALLOC
255 printk("DEBUG_PAGEALLOC");
256 #endif
257 printk("\n");
258 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
259 show_regs(regs);
260 bust_spinlocks(0);
261 add_taint(TAINT_DIE);
262 spin_unlock_irq(&die_lock);
263 if (in_interrupt())
264 panic("Fatal exception in interrupt");
265 if (panic_on_oops)
266 panic("Fatal exception: panic_on_oops");
267 oops_exit();
268 do_exit(SIGSEGV);
269 }
270
report_user_fault(struct pt_regs * regs,int signr)271 static inline void report_user_fault(struct pt_regs *regs, 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%X ", regs->int_code);
280 print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN);
281 printk("\n");
282 show_regs(regs);
283 }
284
is_valid_bugaddr(unsigned long addr)285 int is_valid_bugaddr(unsigned long addr)
286 {
287 return 1;
288 }
289
get_psw_address(struct pt_regs * regs)290 static inline void __user *get_psw_address(struct pt_regs *regs)
291 {
292 return (void __user *)
293 ((regs->psw.addr - (regs->int_code >> 16)) & PSW_ADDR_INSN);
294 }
295
do_trap(struct pt_regs * regs,int si_signo,int si_code,char * str)296 static void __kprobes do_trap(struct pt_regs *regs,
297 int si_signo, int si_code, char *str)
298 {
299 siginfo_t info;
300
301 if (notify_die(DIE_TRAP, str, regs, 0,
302 regs->int_code, si_signo) == NOTIFY_STOP)
303 return;
304
305 if (regs->psw.mask & PSW_MASK_PSTATE) {
306 info.si_signo = si_signo;
307 info.si_errno = 0;
308 info.si_code = si_code;
309 info.si_addr = get_psw_address(regs);
310 force_sig_info(si_signo, &info, current);
311 report_user_fault(regs, si_signo);
312 } else {
313 const struct exception_table_entry *fixup;
314 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
315 if (fixup)
316 regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
317 else {
318 enum bug_trap_type btt;
319
320 btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
321 if (btt == BUG_TRAP_TYPE_WARN)
322 return;
323 die(regs, str);
324 }
325 }
326 }
327
do_per_trap(struct pt_regs * regs)328 void __kprobes do_per_trap(struct pt_regs *regs)
329 {
330 siginfo_t info;
331
332 if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
333 return;
334 if (!current->ptrace)
335 return;
336 info.si_signo = SIGTRAP;
337 info.si_errno = 0;
338 info.si_code = TRAP_HWBKPT;
339 info.si_addr =
340 (void __force __user *) current->thread.per_event.address;
341 force_sig_info(SIGTRAP, &info, current);
342 }
343
default_trap_handler(struct pt_regs * regs)344 static void default_trap_handler(struct pt_regs *regs)
345 {
346 if (regs->psw.mask & PSW_MASK_PSTATE) {
347 report_user_fault(regs, SIGSEGV);
348 do_exit(SIGSEGV);
349 } else
350 die(regs, "Unknown program exception");
351 }
352
353 #define DO_ERROR_INFO(name, signr, sicode, str) \
354 static void name(struct pt_regs *regs) \
355 { \
356 do_trap(regs, signr, sicode, str); \
357 }
358
359 DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
360 "addressing exception")
361 DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
362 "execute exception")
363 DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
364 "fixpoint divide exception")
365 DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
366 "fixpoint overflow exception")
367 DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
368 "HFP overflow exception")
369 DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
370 "HFP underflow exception")
371 DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
372 "HFP significance exception")
373 DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
374 "HFP divide exception")
375 DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
376 "HFP square root exception")
377 DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
378 "operand exception")
379 DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
380 "privileged operation")
381 DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
382 "special operation exception")
383 DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN,
384 "translation exception")
385
do_fp_trap(struct pt_regs * regs,int fpc)386 static inline void do_fp_trap(struct pt_regs *regs, int fpc)
387 {
388 int si_code = 0;
389 /* FPC[2] is Data Exception Code */
390 if ((fpc & 0x00000300) == 0) {
391 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
392 if (fpc & 0x8000) /* invalid fp operation */
393 si_code = FPE_FLTINV;
394 else if (fpc & 0x4000) /* div by 0 */
395 si_code = FPE_FLTDIV;
396 else if (fpc & 0x2000) /* overflow */
397 si_code = FPE_FLTOVF;
398 else if (fpc & 0x1000) /* underflow */
399 si_code = FPE_FLTUND;
400 else if (fpc & 0x0800) /* inexact */
401 si_code = FPE_FLTRES;
402 }
403 do_trap(regs, SIGFPE, si_code, "floating point exception");
404 }
405
illegal_op(struct pt_regs * regs)406 static void __kprobes illegal_op(struct pt_regs *regs)
407 {
408 siginfo_t info;
409 __u8 opcode[6];
410 __u16 __user *location;
411 int signal = 0;
412
413 location = get_psw_address(regs);
414
415 if (regs->psw.mask & PSW_MASK_PSTATE) {
416 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
417 return;
418 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
419 if (current->ptrace) {
420 info.si_signo = SIGTRAP;
421 info.si_errno = 0;
422 info.si_code = TRAP_BRKPT;
423 info.si_addr = location;
424 force_sig_info(SIGTRAP, &info, current);
425 } else
426 signal = SIGILL;
427 #ifdef CONFIG_MATHEMU
428 } else if (opcode[0] == 0xb3) {
429 if (get_user(*((__u16 *) (opcode+2)), location+1))
430 return;
431 signal = math_emu_b3(opcode, regs);
432 } else if (opcode[0] == 0xed) {
433 if (get_user(*((__u32 *) (opcode+2)),
434 (__u32 __user *)(location+1)))
435 return;
436 signal = math_emu_ed(opcode, regs);
437 } else if (*((__u16 *) opcode) == 0xb299) {
438 if (get_user(*((__u16 *) (opcode+2)), location+1))
439 return;
440 signal = math_emu_srnm(opcode, regs);
441 } else if (*((__u16 *) opcode) == 0xb29c) {
442 if (get_user(*((__u16 *) (opcode+2)), location+1))
443 return;
444 signal = math_emu_stfpc(opcode, regs);
445 } else if (*((__u16 *) opcode) == 0xb29d) {
446 if (get_user(*((__u16 *) (opcode+2)), location+1))
447 return;
448 signal = math_emu_lfpc(opcode, regs);
449 #endif
450 } else
451 signal = SIGILL;
452 } else {
453 /*
454 * If we get an illegal op in kernel mode, send it through the
455 * kprobes notifier. If kprobes doesn't pick it up, SIGILL
456 */
457 if (notify_die(DIE_BPT, "bpt", regs, 0,
458 3, SIGTRAP) != NOTIFY_STOP)
459 signal = SIGILL;
460 }
461
462 #ifdef CONFIG_MATHEMU
463 if (signal == SIGFPE)
464 do_fp_trap(regs, current->thread.fp_regs.fpc);
465 else if (signal == SIGSEGV)
466 do_trap(regs, signal, SEGV_MAPERR, "user address fault");
467 else
468 #endif
469 if (signal)
470 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
471 }
472
473
474 #ifdef CONFIG_MATHEMU
specification_exception(struct pt_regs * regs)475 void specification_exception(struct pt_regs *regs)
476 {
477 __u8 opcode[6];
478 __u16 __user *location = NULL;
479 int signal = 0;
480
481 location = (__u16 __user *) get_psw_address(regs);
482
483 if (regs->psw.mask & PSW_MASK_PSTATE) {
484 get_user(*((__u16 *) opcode), location);
485 switch (opcode[0]) {
486 case 0x28: /* LDR Rx,Ry */
487 signal = math_emu_ldr(opcode);
488 break;
489 case 0x38: /* LER Rx,Ry */
490 signal = math_emu_ler(opcode);
491 break;
492 case 0x60: /* STD R,D(X,B) */
493 get_user(*((__u16 *) (opcode+2)), location+1);
494 signal = math_emu_std(opcode, regs);
495 break;
496 case 0x68: /* LD R,D(X,B) */
497 get_user(*((__u16 *) (opcode+2)), location+1);
498 signal = math_emu_ld(opcode, regs);
499 break;
500 case 0x70: /* STE R,D(X,B) */
501 get_user(*((__u16 *) (opcode+2)), location+1);
502 signal = math_emu_ste(opcode, regs);
503 break;
504 case 0x78: /* LE R,D(X,B) */
505 get_user(*((__u16 *) (opcode+2)), location+1);
506 signal = math_emu_le(opcode, regs);
507 break;
508 default:
509 signal = SIGILL;
510 break;
511 }
512 } else
513 signal = SIGILL;
514
515 if (signal == SIGFPE)
516 do_fp_trap(regs, current->thread.fp_regs.fpc);
517 else if (signal)
518 do_trap(regs, signal, ILL_ILLOPN, "specification exception");
519 }
520 #else
521 DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
522 "specification exception");
523 #endif
524
data_exception(struct pt_regs * regs)525 static void data_exception(struct pt_regs *regs)
526 {
527 __u16 __user *location;
528 int signal = 0;
529
530 location = get_psw_address(regs);
531
532 if (MACHINE_HAS_IEEE)
533 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
534
535 #ifdef CONFIG_MATHEMU
536 else if (regs->psw.mask & PSW_MASK_PSTATE) {
537 __u8 opcode[6];
538 get_user(*((__u16 *) opcode), location);
539 switch (opcode[0]) {
540 case 0x28: /* LDR Rx,Ry */
541 signal = math_emu_ldr(opcode);
542 break;
543 case 0x38: /* LER Rx,Ry */
544 signal = math_emu_ler(opcode);
545 break;
546 case 0x60: /* STD R,D(X,B) */
547 get_user(*((__u16 *) (opcode+2)), location+1);
548 signal = math_emu_std(opcode, regs);
549 break;
550 case 0x68: /* LD R,D(X,B) */
551 get_user(*((__u16 *) (opcode+2)), location+1);
552 signal = math_emu_ld(opcode, regs);
553 break;
554 case 0x70: /* STE R,D(X,B) */
555 get_user(*((__u16 *) (opcode+2)), location+1);
556 signal = math_emu_ste(opcode, regs);
557 break;
558 case 0x78: /* LE R,D(X,B) */
559 get_user(*((__u16 *) (opcode+2)), location+1);
560 signal = math_emu_le(opcode, regs);
561 break;
562 case 0xb3:
563 get_user(*((__u16 *) (opcode+2)), location+1);
564 signal = math_emu_b3(opcode, regs);
565 break;
566 case 0xed:
567 get_user(*((__u32 *) (opcode+2)),
568 (__u32 __user *)(location+1));
569 signal = math_emu_ed(opcode, regs);
570 break;
571 case 0xb2:
572 if (opcode[1] == 0x99) {
573 get_user(*((__u16 *) (opcode+2)), location+1);
574 signal = math_emu_srnm(opcode, regs);
575 } else if (opcode[1] == 0x9c) {
576 get_user(*((__u16 *) (opcode+2)), location+1);
577 signal = math_emu_stfpc(opcode, regs);
578 } else if (opcode[1] == 0x9d) {
579 get_user(*((__u16 *) (opcode+2)), location+1);
580 signal = math_emu_lfpc(opcode, regs);
581 } else
582 signal = SIGILL;
583 break;
584 default:
585 signal = SIGILL;
586 break;
587 }
588 }
589 #endif
590 if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
591 signal = SIGFPE;
592 else
593 signal = SIGILL;
594 if (signal == SIGFPE)
595 do_fp_trap(regs, current->thread.fp_regs.fpc);
596 else if (signal)
597 do_trap(regs, signal, ILL_ILLOPN, "data exception");
598 }
599
space_switch_exception(struct pt_regs * regs)600 static void space_switch_exception(struct pt_regs *regs)
601 {
602 /* Set user psw back to home space mode. */
603 if (regs->psw.mask & PSW_MASK_PSTATE)
604 regs->psw.mask |= PSW_ASC_HOME;
605 /* Send SIGILL. */
606 do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
607 }
608
kernel_stack_overflow(struct pt_regs * regs)609 void __kprobes kernel_stack_overflow(struct pt_regs * regs)
610 {
611 bust_spinlocks(1);
612 printk("Kernel stack overflow.\n");
613 show_regs(regs);
614 bust_spinlocks(0);
615 panic("Corrupt kernel stack, can't continue.");
616 }
617
618 /* init is done in lowcore.S and head.S */
619
trap_init(void)620 void __init trap_init(void)
621 {
622 int i;
623
624 for (i = 0; i < 128; i++)
625 pgm_check_table[i] = &default_trap_handler;
626 pgm_check_table[1] = &illegal_op;
627 pgm_check_table[2] = &privileged_op;
628 pgm_check_table[3] = &execute_exception;
629 pgm_check_table[4] = &do_protection_exception;
630 pgm_check_table[5] = &addressing_exception;
631 pgm_check_table[6] = &specification_exception;
632 pgm_check_table[7] = &data_exception;
633 pgm_check_table[8] = &overflow_exception;
634 pgm_check_table[9] = ÷_exception;
635 pgm_check_table[0x0A] = &overflow_exception;
636 pgm_check_table[0x0B] = ÷_exception;
637 pgm_check_table[0x0C] = &hfp_overflow_exception;
638 pgm_check_table[0x0D] = &hfp_underflow_exception;
639 pgm_check_table[0x0E] = &hfp_significance_exception;
640 pgm_check_table[0x0F] = &hfp_divide_exception;
641 pgm_check_table[0x10] = &do_dat_exception;
642 pgm_check_table[0x11] = &do_dat_exception;
643 pgm_check_table[0x12] = &translation_exception;
644 pgm_check_table[0x13] = &special_op_exception;
645 #ifdef CONFIG_64BIT
646 pgm_check_table[0x38] = &do_asce_exception;
647 pgm_check_table[0x39] = &do_dat_exception;
648 pgm_check_table[0x3A] = &do_dat_exception;
649 pgm_check_table[0x3B] = &do_dat_exception;
650 #endif /* CONFIG_64BIT */
651 pgm_check_table[0x15] = &operand_exception;
652 pgm_check_table[0x1C] = &space_switch_exception;
653 pgm_check_table[0x1D] = &hfp_sqrt_exception;
654 /* Enable machine checks early. */
655 local_mcck_enable();
656 }
657