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traps.c
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1 /*
2  * linux/arch/parisc/traps.c
3  *
4  * Copyright (C) 1991, 1992 Linus Torvalds
5  * Copyright (C) 1999, 2000 Philipp Rumpf <[email protected]>
6  */
7 
8 /*
9  * 'Traps.c' handles hardware traps and faults after we have saved some
10  * state in 'asm.s'.
11  */
12 
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/timer.h>
19 #include <linux/delay.h>
20 #include <linux/mm.h>
21 #include <linux/module.h>
22 #include <linux/smp.h>
23 #include <linux/spinlock.h>
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/console.h>
27 #include <linux/bug.h>
28 
29 #include <asm/assembly.h>
30 #include <asm/uaccess.h>
31 #include <asm/io.h>
32 #include <asm/irq.h>
33 #include <asm/traps.h>
34 #include <asm/unaligned.h>
35 #include <linux/atomic.h>
36 #include <asm/smp.h>
37 #include <asm/pdc.h>
38 #include <asm/pdc_chassis.h>
39 #include <asm/unwind.h>
40 #include <asm/tlbflush.h>
41 #include <asm/cacheflush.h>
42 
43 #include "../math-emu/math-emu.h" /* for handle_fpe() */
44 
45 #define PRINT_USER_FAULTS /* (turn this on if you want user faults to be */
46  /* dumped to the console via printk) */
47 
48 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
49 DEFINE_SPINLOCK(pa_dbit_lock);
50 #endif
51 
52 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
53  struct pt_regs *regs);
54 
55 static int printbinary(char *buf, unsigned long x, int nbits)
56 {
57  unsigned long mask = 1UL << (nbits - 1);
58  while (mask != 0) {
59  *buf++ = (mask & x ? '1' : '0');
60  mask >>= 1;
61  }
62  *buf = '\0';
63 
64  return nbits;
65 }
66 
67 #ifdef CONFIG_64BIT
68 #define RFMT "%016lx"
69 #else
70 #define RFMT "%08lx"
71 #endif
72 #define FFMT "%016llx" /* fpregs are 64-bit always */
73 
74 #define PRINTREGS(lvl,r,f,fmt,x) \
75  printk("%s%s%02d-%02d " fmt " " fmt " " fmt " " fmt "\n", \
76  lvl, f, (x), (x+3), (r)[(x)+0], (r)[(x)+1], \
77  (r)[(x)+2], (r)[(x)+3])
78 
79 static void print_gr(char *level, struct pt_regs *regs)
80 {
81  int i;
82  char buf[64];
83 
84  printk("%s\n", level);
85  printk("%s YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI\n", level);
86  printbinary(buf, regs->gr[0], 32);
87  printk("%sPSW: %s %s\n", level, buf, print_tainted());
88 
89  for (i = 0; i < 32; i += 4)
90  PRINTREGS(level, regs->gr, "r", RFMT, i);
91 }
92 
93 static void print_fr(char *level, struct pt_regs *regs)
94 {
95  int i;
96  char buf[64];
97  struct { u32 sw[2]; } s;
98 
99  /* FR are 64bit everywhere. Need to use asm to get the content
100  * of fpsr/fper1, and we assume that we won't have a FP Identify
101  * in our way, otherwise we're screwed.
102  * The fldd is used to restore the T-bit if there was one, as the
103  * store clears it anyway.
104  * PA2.0 book says "thou shall not use fstw on FPSR/FPERs" - T-Bone */
105  asm volatile ("fstd %%fr0,0(%1) \n\t"
106  "fldd 0(%1),%%fr0 \n\t"
107  : "=m" (s) : "r" (&s) : "r0");
108 
109  printk("%s\n", level);
110  printk("%s VZOUICununcqcqcqcqcqcrmunTDVZOUI\n", level);
111  printbinary(buf, s.sw[0], 32);
112  printk("%sFPSR: %s\n", level, buf);
113  printk("%sFPER1: %08x\n", level, s.sw[1]);
114 
115  /* here we'll print fr0 again, tho it'll be meaningless */
116  for (i = 0; i < 32; i += 4)
117  PRINTREGS(level, regs->fr, "fr", FFMT, i);
118 }
119 
120 void show_regs(struct pt_regs *regs)
121 {
122  int i, user;
123  char *level;
124  unsigned long cr30, cr31;
125 
126  user = user_mode(regs);
127  level = user ? KERN_DEBUG : KERN_CRIT;
128 
129  print_gr(level, regs);
130 
131  for (i = 0; i < 8; i += 4)
132  PRINTREGS(level, regs->sr, "sr", RFMT, i);
133 
134  if (user)
135  print_fr(level, regs);
136 
137  cr30 = mfctl(30);
138  cr31 = mfctl(31);
139  printk("%s\n", level);
140  printk("%sIASQ: " RFMT " " RFMT " IAOQ: " RFMT " " RFMT "\n",
141  level, regs->iasq[0], regs->iasq[1], regs->iaoq[0], regs->iaoq[1]);
142  printk("%s IIR: %08lx ISR: " RFMT " IOR: " RFMT "\n",
143  level, regs->iir, regs->isr, regs->ior);
144  printk("%s CPU: %8d CR30: " RFMT " CR31: " RFMT "\n",
145  level, current_thread_info()->cpu, cr30, cr31);
146  printk("%s ORIG_R28: " RFMT "\n", level, regs->orig_r28);
147 
148  if (user) {
149  printk("%s IAOQ[0]: " RFMT "\n", level, regs->iaoq[0]);
150  printk("%s IAOQ[1]: " RFMT "\n", level, regs->iaoq[1]);
151  printk("%s RP(r2): " RFMT "\n", level, regs->gr[2]);
152  } else {
153  printk("%s IAOQ[0]: %pS\n", level, (void *) regs->iaoq[0]);
154  printk("%s IAOQ[1]: %pS\n", level, (void *) regs->iaoq[1]);
155  printk("%s RP(r2): %pS\n", level, (void *) regs->gr[2]);
156 
157  parisc_show_stack(current, NULL, regs);
158  }
159 }
160 
161 
162 void dump_stack(void)
163 {
164  show_stack(NULL, NULL);
165 }
166 
168 
169 static void do_show_stack(struct unwind_frame_info *info)
170 {
171  int i = 1;
172 
173  printk(KERN_CRIT "Backtrace:\n");
174  while (i <= 16) {
175  if (unwind_once(info) < 0 || info->ip == 0)
176  break;
177 
178  if (__kernel_text_address(info->ip)) {
179  printk(KERN_CRIT " [<" RFMT ">] %pS\n",
180  info->ip, (void *) info->ip);
181  i++;
182  }
183  }
184  printk(KERN_CRIT "\n");
185 }
186 
187 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
188  struct pt_regs *regs)
189 {
190  struct unwind_frame_info info;
191  struct task_struct *t;
192 
193  t = task ? task : current;
194  if (regs) {
195  unwind_frame_init(&info, t, regs);
196  goto show_stack;
197  }
198 
199  if (t == current) {
200  unsigned long sp;
201 
202 HERE:
203  asm volatile ("copy %%r30, %0" : "=r"(sp));
204  {
205  struct pt_regs r;
206 
207  memset(&r, 0, sizeof(struct pt_regs));
208  r.iaoq[0] = (unsigned long)&&HERE;
209  r.gr[2] = (unsigned long)__builtin_return_address(0);
210  r.gr[30] = sp;
211 
212  unwind_frame_init(&info, current, &r);
213  }
214  } else {
216  }
217 
218 show_stack:
219  do_show_stack(&info);
220 }
221 
222 void show_stack(struct task_struct *t, unsigned long *sp)
223 {
224  return parisc_show_stack(t, sp, NULL);
225 }
226 
227 int is_valid_bugaddr(unsigned long iaoq)
228 {
229  return 1;
230 }
231 
232 void die_if_kernel(char *str, struct pt_regs *regs, long err)
233 {
234  if (user_mode(regs)) {
235  if (err == 0)
236  return; /* STFU */
237 
238  printk(KERN_CRIT "%s (pid %d): %s (code %ld) at " RFMT "\n",
239  current->comm, task_pid_nr(current), str, err, regs->iaoq[0]);
240 #ifdef PRINT_USER_FAULTS
241  /* XXX for debugging only */
242  show_regs(regs);
243 #endif
244  return;
245  }
246 
247  oops_in_progress = 1;
248 
249  oops_enter();
250 
251  /* Amuse the user in a SPARC fashion */
252  if (err) printk(KERN_CRIT
253  " _______________________________ \n"
254  " < Your System ate a SPARC! Gah! >\n"
255  " ------------------------------- \n"
256  " \\ ^__^\n"
257  " (__)\\ )\\/\\\n"
258  " U ||----w |\n"
259  " || ||\n");
260 
261  /* unlock the pdc lock if necessary */
263 
264  /* maybe the kernel hasn't booted very far yet and hasn't been able
265  * to initialize the serial or STI console. In that case we should
266  * re-enable the pdc console, so that the user will be able to
267  * identify the problem. */
268  if (!console_drivers)
270 
271  if (err)
272  printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n",
273  current->comm, task_pid_nr(current), str, err);
274 
275  /* Wot's wrong wif bein' racy? */
276  if (current->thread.flags & PARISC_KERNEL_DEATH) {
277  printk(KERN_CRIT "%s() recursion detected.\n", __func__);
279  while (1);
280  }
281  current->thread.flags |= PARISC_KERNEL_DEATH;
282 
283  show_regs(regs);
284  dump_stack();
286 
287  if (in_interrupt())
288  panic("Fatal exception in interrupt");
289 
290  if (panic_on_oops) {
291  printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
292  ssleep(5);
293  panic("Fatal exception");
294  }
295 
296  oops_exit();
297  do_exit(SIGSEGV);
298 }
299 
300 int syscall_ipi(int (*syscall) (struct pt_regs *), struct pt_regs *regs)
301 {
302  return syscall(regs);
303 }
304 
305 /* gdb uses break 4,8 */
306 #define GDB_BREAK_INSN 0x10004
307 static void handle_gdb_break(struct pt_regs *regs, int wot)
308 {
309  struct siginfo si;
310 
311  si.si_signo = SIGTRAP;
312  si.si_errno = 0;
313  si.si_code = wot;
314  si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
316 }
317 
318 static void handle_break(struct pt_regs *regs)
319 {
320  unsigned iir = regs->iir;
321 
322  if (unlikely(iir == PARISC_BUG_BREAK_INSN && !user_mode(regs))) {
323  /* check if a BUG() or WARN() trapped here. */
324  enum bug_trap_type tt;
325  tt = report_bug(regs->iaoq[0] & ~3, regs);
326  if (tt == BUG_TRAP_TYPE_WARN) {
327  regs->iaoq[0] += 4;
328  regs->iaoq[1] += 4;
329  return; /* return to next instruction when WARN_ON(). */
330  }
331  die_if_kernel("Unknown kernel breakpoint", regs,
332  (tt == BUG_TRAP_TYPE_NONE) ? 9 : 0);
333  }
334 
335 #ifdef PRINT_USER_FAULTS
336  if (unlikely(iir != GDB_BREAK_INSN)) {
337  printk(KERN_DEBUG "break %d,%d: pid=%d command='%s'\n",
338  iir & 31, (iir>>13) & ((1<<13)-1),
339  task_pid_nr(current), current->comm);
340  show_regs(regs);
341  }
342 #endif
343 
344  /* send standard GDB signal */
345  handle_gdb_break(regs, TRAP_BRKPT);
346 }
347 
348 static void default_trap(int code, struct pt_regs *regs)
349 {
350  printk(KERN_ERR "Trap %d on CPU %d\n", code, smp_processor_id());
351  show_regs(regs);
352 }
353 
354 void (*cpu_lpmc) (int code, struct pt_regs *regs) __read_mostly = default_trap;
355 
356 
358 {
359  register int i;
360  extern unsigned int hpmc_pim_data[];
361  struct pdc_hpmc_pim_11 *pim_narrow;
362  struct pdc_hpmc_pim_20 *pim_wide;
363 
364  if (boot_cpu_data.cpu_type >= pcxu) {
365 
366  pim_wide = (struct pdc_hpmc_pim_20 *)hpmc_pim_data;
367 
368  /*
369  * Note: The following code will probably generate a
370  * bunch of truncation error warnings from the compiler.
371  * Could be handled with an ifdef, but perhaps there
372  * is a better way.
373  */
374 
375  regs->gr[0] = pim_wide->cr[22];
376 
377  for (i = 1; i < 32; i++)
378  regs->gr[i] = pim_wide->gr[i];
379 
380  for (i = 0; i < 32; i++)
381  regs->fr[i] = pim_wide->fr[i];
382 
383  for (i = 0; i < 8; i++)
384  regs->sr[i] = pim_wide->sr[i];
385 
386  regs->iasq[0] = pim_wide->cr[17];
387  regs->iasq[1] = pim_wide->iasq_back;
388  regs->iaoq[0] = pim_wide->cr[18];
389  regs->iaoq[1] = pim_wide->iaoq_back;
390 
391  regs->sar = pim_wide->cr[11];
392  regs->iir = pim_wide->cr[19];
393  regs->isr = pim_wide->cr[20];
394  regs->ior = pim_wide->cr[21];
395  }
396  else {
397  pim_narrow = (struct pdc_hpmc_pim_11 *)hpmc_pim_data;
398 
399  regs->gr[0] = pim_narrow->cr[22];
400 
401  for (i = 1; i < 32; i++)
402  regs->gr[i] = pim_narrow->gr[i];
403 
404  for (i = 0; i < 32; i++)
405  regs->fr[i] = pim_narrow->fr[i];
406 
407  for (i = 0; i < 8; i++)
408  regs->sr[i] = pim_narrow->sr[i];
409 
410  regs->iasq[0] = pim_narrow->cr[17];
411  regs->iasq[1] = pim_narrow->iasq_back;
412  regs->iaoq[0] = pim_narrow->cr[18];
413  regs->iaoq[1] = pim_narrow->iaoq_back;
414 
415  regs->sar = pim_narrow->cr[11];
416  regs->iir = pim_narrow->cr[19];
417  regs->isr = pim_narrow->cr[20];
418  regs->ior = pim_narrow->cr[21];
419  }
420 
421  /*
422  * The following fields only have meaning if we came through
423  * another path. So just zero them here.
424  */
425 
426  regs->ksp = 0;
427  regs->kpc = 0;
428  regs->orig_r28 = 0;
429 }
430 
431 
432 /*
433  * This routine is called as a last resort when everything else
434  * has gone clearly wrong. We get called for faults in kernel space,
435  * and HPMC's.
436  */
437 void parisc_terminate(char *msg, struct pt_regs *regs, int code, unsigned long offset)
438 {
439  static DEFINE_SPINLOCK(terminate_lock);
440 
441  oops_in_progress = 1;
442 
443  set_eiem(0);
445  spin_lock(&terminate_lock);
446 
447  /* unlock the pdc lock if necessary */
449 
450  /* restart pdc console if necessary */
451  if (!console_drivers)
453 
454  /* Not all paths will gutter the processor... */
455  switch(code){
456 
457  case 1:
459  break;
460 
461  default:
462  /* Fall through */
463  break;
464 
465  }
466 
467  {
468  /* show_stack(NULL, (unsigned long *)regs->gr[30]); */
469  struct unwind_frame_info info;
470  unwind_frame_init(&info, current, regs);
471  do_show_stack(&info);
472  }
473 
474  printk("\n");
475  printk(KERN_CRIT "%s: Code=%d regs=%p (Addr=" RFMT ")\n",
476  msg, code, regs, offset);
477  show_regs(regs);
478 
479  spin_unlock(&terminate_lock);
480 
481  /* put soft power button back under hardware control;
482  * if the user had pressed it once at any time, the
483  * system will shut down immediately right here. */
485 
486  /* Call kernel panic() so reboot timeouts work properly
487  * FIXME: This function should be on the list of
488  * panic notifiers, and we should call panic
489  * directly from the location that we wish.
490  * e.g. We should not call panic from
491  * parisc_terminate, but rather the oter way around.
492  * This hack works, prints the panic message twice,
493  * and it enables reboot timers!
494  */
495  panic(msg);
496 }
497 
498 void notrace handle_interruption(int code, struct pt_regs *regs)
499 {
500  unsigned long fault_address = 0;
501  unsigned long fault_space = 0;
502  struct siginfo si;
503 
504  if (code == 1)
505  pdc_console_restart(); /* switch back to pdc if HPMC */
506  else
508 
509  /* Security check:
510  * If the priority level is still user, and the
511  * faulting space is not equal to the active space
512  * then the user is attempting something in a space
513  * that does not belong to them. Kill the process.
514  *
515  * This is normally the situation when the user
516  * attempts to jump into the kernel space at the
517  * wrong offset, be it at the gateway page or a
518  * random location.
519  *
520  * We cannot normally signal the process because it
521  * could *be* on the gateway page, and processes
522  * executing on the gateway page can't have signals
523  * delivered.
524  *
525  * We merely readjust the address into the users
526  * space, at a destination address of zero, and
527  * allow processing to continue.
528  */
529  if (((unsigned long)regs->iaoq[0] & 3) &&
530  ((unsigned long)regs->iasq[0] != (unsigned long)regs->sr[7])) {
531  /* Kill the user process later */
532  regs->iaoq[0] = 0 | 3;
533  regs->iaoq[1] = regs->iaoq[0] + 4;
534  regs->iasq[0] = regs->iasq[1] = regs->sr[7];
535  regs->gr[0] &= ~PSW_B;
536  return;
537  }
538 
539 #if 0
540  printk(KERN_CRIT "Interruption # %d\n", code);
541 #endif
542 
543  switch(code) {
544 
545  case 1:
546  /* High-priority machine check (HPMC) */
547 
548  /* set up a new led state on systems shipped with a LED State panel */
550 
551  parisc_terminate("High Priority Machine Check (HPMC)",
552  regs, code, 0);
553  /* NOT REACHED */
554 
555  case 2:
556  /* Power failure interrupt */
557  printk(KERN_CRIT "Power failure interrupt !\n");
558  return;
559 
560  case 3:
561  /* Recovery counter trap */
562  regs->gr[0] &= ~PSW_R;
563  if (user_space(regs))
564  handle_gdb_break(regs, TRAP_TRACE);
565  /* else this must be the start of a syscall - just let it run */
566  return;
567 
568  case 5:
569  /* Low-priority machine check */
571 
572  flush_cache_all();
573  flush_tlb_all();
574  cpu_lpmc(5, regs);
575  return;
576 
577  case 6:
578  /* Instruction TLB miss fault/Instruction page fault */
579  fault_address = regs->iaoq[0];
580  fault_space = regs->iasq[0];
581  break;
582 
583  case 8:
584  /* Illegal instruction trap */
585  die_if_kernel("Illegal instruction", regs, code);
586  si.si_code = ILL_ILLOPC;
587  goto give_sigill;
588 
589  case 9:
590  /* Break instruction trap */
591  handle_break(regs);
592  return;
593 
594  case 10:
595  /* Privileged operation trap */
596  die_if_kernel("Privileged operation", regs, code);
597  si.si_code = ILL_PRVOPC;
598  goto give_sigill;
599 
600  case 11:
601  /* Privileged register trap */
602  if ((regs->iir & 0xffdfffe0) == 0x034008a0) {
603 
604  /* This is a MFCTL cr26/cr27 to gr instruction.
605  * PCXS traps on this, so we need to emulate it.
606  */
607 
608  if (regs->iir & 0x00200000)
609  regs->gr[regs->iir & 0x1f] = mfctl(27);
610  else
611  regs->gr[regs->iir & 0x1f] = mfctl(26);
612 
613  regs->iaoq[0] = regs->iaoq[1];
614  regs->iaoq[1] += 4;
615  regs->iasq[0] = regs->iasq[1];
616  return;
617  }
618 
619  die_if_kernel("Privileged register usage", regs, code);
620  si.si_code = ILL_PRVREG;
621  give_sigill:
622  si.si_signo = SIGILL;
623  si.si_errno = 0;
624  si.si_addr = (void __user *) regs->iaoq[0];
626  return;
627 
628  case 12:
629  /* Overflow Trap, let the userland signal handler do the cleanup */
630  si.si_signo = SIGFPE;
631  si.si_code = FPE_INTOVF;
632  si.si_addr = (void __user *) regs->iaoq[0];
634  return;
635 
636  case 13:
637  /* Conditional Trap
638  The condition succeeds in an instruction which traps
639  on condition */
640  if(user_mode(regs)){
641  si.si_signo = SIGFPE;
642  /* Set to zero, and let the userspace app figure it out from
643  the insn pointed to by si_addr */
644  si.si_code = 0;
645  si.si_addr = (void __user *) regs->iaoq[0];
647  return;
648  }
649  /* The kernel doesn't want to handle condition codes */
650  break;
651 
652  case 14:
653  /* Assist Exception Trap, i.e. floating point exception. */
654  die_if_kernel("Floating point exception", regs, 0); /* quiet */
655  handle_fpe(regs);
656  return;
657 
658  case 15:
659  /* Data TLB miss fault/Data page fault */
660  /* Fall through */
661  case 16:
662  /* Non-access instruction TLB miss fault */
663  /* The instruction TLB entry needed for the target address of the FIC
664  is absent, and hardware can't find it, so we get to cleanup */
665  /* Fall through */
666  case 17:
667  /* Non-access data TLB miss fault/Non-access data page fault */
668  /* FIXME:
669  Still need to add slow path emulation code here!
670  If the insn used a non-shadow register, then the tlb
671  handlers could not have their side-effect (e.g. probe
672  writing to a target register) emulated since rfir would
673  erase the changes to said register. Instead we have to
674  setup everything, call this function we are in, and emulate
675  by hand. Technically we need to emulate:
676  fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw
677  */
678  fault_address = regs->ior;
679  fault_space = regs->isr;
680  break;
681 
682  case 18:
683  /* PCXS only -- later cpu's split this into types 26,27 & 28 */
684  /* Check for unaligned access */
685  if (check_unaligned(regs)) {
686  handle_unaligned(regs);
687  return;
688  }
689  /* Fall Through */
690  case 26:
691  /* PCXL: Data memory access rights trap */
692  fault_address = regs->ior;
693  fault_space = regs->isr;
694  break;
695 
696  case 19:
697  /* Data memory break trap */
698  regs->gr[0] |= PSW_X; /* So we can single-step over the trap */
699  /* fall thru */
700  case 21:
701  /* Page reference trap */
702  handle_gdb_break(regs, TRAP_HWBKPT);
703  return;
704 
705  case 25:
706  /* Taken branch trap */
707  regs->gr[0] &= ~PSW_T;
708  if (user_space(regs))
709  handle_gdb_break(regs, TRAP_BRANCH);
710  /* else this must be the start of a syscall - just let it
711  * run.
712  */
713  return;
714 
715  case 7:
716  /* Instruction access rights */
717  /* PCXL: Instruction memory protection trap */
718 
719  /*
720  * This could be caused by either: 1) a process attempting
721  * to execute within a vma that does not have execute
722  * permission, or 2) an access rights violation caused by a
723  * flush only translation set up by ptep_get_and_clear().
724  * So we check the vma permissions to differentiate the two.
725  * If the vma indicates we have execute permission, then
726  * the cause is the latter one. In this case, we need to
727  * call do_page_fault() to fix the problem.
728  */
729 
730  if (user_mode(regs)) {
731  struct vm_area_struct *vma;
732 
733  down_read(&current->mm->mmap_sem);
734  vma = find_vma(current->mm,regs->iaoq[0]);
735  if (vma && (regs->iaoq[0] >= vma->vm_start)
736  && (vma->vm_flags & VM_EXEC)) {
737 
738  fault_address = regs->iaoq[0];
739  fault_space = regs->iasq[0];
740 
741  up_read(&current->mm->mmap_sem);
742  break; /* call do_page_fault() */
743  }
744  up_read(&current->mm->mmap_sem);
745  }
746  /* Fall Through */
747  case 27:
748  /* Data memory protection ID trap */
749  if (code == 27 && !user_mode(regs) &&
750  fixup_exception(regs))
751  return;
752 
753  die_if_kernel("Protection id trap", regs, code);
754  si.si_code = SEGV_MAPERR;
755  si.si_signo = SIGSEGV;
756  si.si_errno = 0;
757  if (code == 7)
758  si.si_addr = (void __user *) regs->iaoq[0];
759  else
760  si.si_addr = (void __user *) regs->ior;
762  return;
763 
764  case 28:
765  /* Unaligned data reference trap */
766  handle_unaligned(regs);
767  return;
768 
769  default:
770  if (user_mode(regs)) {
771 #ifdef PRINT_USER_FAULTS
772  printk(KERN_DEBUG "\nhandle_interruption() pid=%d command='%s'\n",
773  task_pid_nr(current), current->comm);
774  show_regs(regs);
775 #endif
776  /* SIGBUS, for lack of a better one. */
777  si.si_signo = SIGBUS;
778  si.si_code = BUS_OBJERR;
779  si.si_errno = 0;
780  si.si_addr = (void __user *) regs->ior;
782  return;
783  }
785 
786  parisc_terminate("Unexpected interruption", regs, code, 0);
787  /* NOT REACHED */
788  }
789 
790  if (user_mode(regs)) {
791  if ((fault_space >> SPACEID_SHIFT) != (regs->sr[7] >> SPACEID_SHIFT)) {
792 #ifdef PRINT_USER_FAULTS
793  if (fault_space == 0)
794  printk(KERN_DEBUG "User Fault on Kernel Space ");
795  else
796  printk(KERN_DEBUG "User Fault (long pointer) (fault %d) ",
797  code);
798  printk(KERN_CONT "pid=%d command='%s'\n",
799  task_pid_nr(current), current->comm);
800  show_regs(regs);
801 #endif
802  si.si_signo = SIGSEGV;
803  si.si_errno = 0;
804  si.si_code = SEGV_MAPERR;
805  si.si_addr = (void __user *) regs->ior;
807  return;
808  }
809  }
810  else {
811 
812  /*
813  * The kernel should never fault on its own address space.
814  */
815 
816  if (fault_space == 0)
817  {
819  parisc_terminate("Kernel Fault", regs, code, fault_address);
820 
821  }
822  }
823 
824  do_page_fault(regs, code, fault_address);
825 }
826 
827 
828 int __init check_ivt(void *iva)
829 {
830  extern u32 os_hpmc_size;
831  extern const u32 os_hpmc[];
832 
833  int i;
834  u32 check = 0;
835  u32 *ivap;
836  u32 *hpmcp;
837  u32 length;
838 
839  if (strcmp((char *)iva, "cows can fly"))
840  return -1;
841 
842  ivap = (u32 *)iva;
843 
844  for (i = 0; i < 8; i++)
845  *ivap++ = 0;
846 
847  /* Compute Checksum for HPMC handler */
848  length = os_hpmc_size;
849  ivap[7] = length;
850 
851  hpmcp = (u32 *)os_hpmc;
852 
853  for (i=0; i<length/4; i++)
854  check += *hpmcp++;
855 
856  for (i=0; i<8; i++)
857  check += ivap[i];
858 
859  ivap[5] = -check;
860 
861  return 0;
862 }
863 
864 #ifndef CONFIG_64BIT
865 extern const void fault_vector_11;
866 #endif
867 extern const void fault_vector_20;
868 
869 void __init trap_init(void)
870 {
871  void *iva;
872 
873  if (boot_cpu_data.cpu_type >= pcxu)
874  iva = (void *) &fault_vector_20;
875  else
876 #ifdef CONFIG_64BIT
877  panic("Can't boot 64-bit OS on PA1.1 processor!");
878 #else
879  iva = (void *) &fault_vector_11;
880 #endif
881 
882  if (check_ivt(iva))
883  panic("IVT invalid");
884 }