1 /*
2 * linux/arch/parisc/traps.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 1999, 2000 Philipp Rumpf <prumpf@tux.org>
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/system.h>
31 #include <asm/uaccess.h>
32 #include <asm/io.h>
33 #include <asm/irq.h>
34 #include <asm/traps.h>
35 #include <asm/unaligned.h>
36 #include <asm/atomic.h>
37 #include <asm/smp.h>
38 #include <asm/pdc.h>
39 #include <asm/pdc_chassis.h>
40 #include <asm/unwind.h>
41 #include <asm/tlbflush.h>
42 #include <asm/cacheflush.h>
43
44 #include "../math-emu/math-emu.h" /* for handle_fpe() */
45
46 #define PRINT_USER_FAULTS /* (turn this on if you want user faults to be */
47 /* dumped to the console via printk) */
48
49 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
50 DEFINE_SPINLOCK(pa_dbit_lock);
51 #endif
52
53 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
54 struct pt_regs *regs);
55
printbinary(char * buf,unsigned long x,int nbits)56 static int printbinary(char *buf, unsigned long x, int nbits)
57 {
58 unsigned long mask = 1UL << (nbits - 1);
59 while (mask != 0) {
60 *buf++ = (mask & x ? '1' : '0');
61 mask >>= 1;
62 }
63 *buf = '\0';
64
65 return nbits;
66 }
67
68 #ifdef CONFIG_64BIT
69 #define RFMT "%016lx"
70 #else
71 #define RFMT "%08lx"
72 #endif
73 #define FFMT "%016llx" /* fpregs are 64-bit always */
74
75 #define PRINTREGS(lvl,r,f,fmt,x) \
76 printk("%s%s%02d-%02d " fmt " " fmt " " fmt " " fmt "\n", \
77 lvl, f, (x), (x+3), (r)[(x)+0], (r)[(x)+1], \
78 (r)[(x)+2], (r)[(x)+3])
79
print_gr(char * level,struct pt_regs * regs)80 static void print_gr(char *level, struct pt_regs *regs)
81 {
82 int i;
83 char buf[64];
84
85 printk("%s\n", level);
86 printk("%s YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI\n", level);
87 printbinary(buf, regs->gr[0], 32);
88 printk("%sPSW: %s %s\n", level, buf, print_tainted());
89
90 for (i = 0; i < 32; i += 4)
91 PRINTREGS(level, regs->gr, "r", RFMT, i);
92 }
93
print_fr(char * level,struct pt_regs * regs)94 static void print_fr(char *level, struct pt_regs *regs)
95 {
96 int i;
97 char buf[64];
98 struct { u32 sw[2]; } s;
99
100 /* FR are 64bit everywhere. Need to use asm to get the content
101 * of fpsr/fper1, and we assume that we won't have a FP Identify
102 * in our way, otherwise we're screwed.
103 * The fldd is used to restore the T-bit if there was one, as the
104 * store clears it anyway.
105 * PA2.0 book says "thou shall not use fstw on FPSR/FPERs" - T-Bone */
106 asm volatile ("fstd %%fr0,0(%1) \n\t"
107 "fldd 0(%1),%%fr0 \n\t"
108 : "=m" (s) : "r" (&s) : "r0");
109
110 printk("%s\n", level);
111 printk("%s VZOUICununcqcqcqcqcqcrmunTDVZOUI\n", level);
112 printbinary(buf, s.sw[0], 32);
113 printk("%sFPSR: %s\n", level, buf);
114 printk("%sFPER1: %08x\n", level, s.sw[1]);
115
116 /* here we'll print fr0 again, tho it'll be meaningless */
117 for (i = 0; i < 32; i += 4)
118 PRINTREGS(level, regs->fr, "fr", FFMT, i);
119 }
120
show_regs(struct pt_regs * regs)121 void show_regs(struct pt_regs *regs)
122 {
123 int i, user;
124 char *level;
125 unsigned long cr30, cr31;
126
127 user = user_mode(regs);
128 level = user ? KERN_DEBUG : KERN_CRIT;
129
130 print_gr(level, regs);
131
132 for (i = 0; i < 8; i += 4)
133 PRINTREGS(level, regs->sr, "sr", RFMT, i);
134
135 if (user)
136 print_fr(level, regs);
137
138 cr30 = mfctl(30);
139 cr31 = mfctl(31);
140 printk("%s\n", level);
141 printk("%sIASQ: " RFMT " " RFMT " IAOQ: " RFMT " " RFMT "\n",
142 level, regs->iasq[0], regs->iasq[1], regs->iaoq[0], regs->iaoq[1]);
143 printk("%s IIR: %08lx ISR: " RFMT " IOR: " RFMT "\n",
144 level, regs->iir, regs->isr, regs->ior);
145 printk("%s CPU: %8d CR30: " RFMT " CR31: " RFMT "\n",
146 level, current_thread_info()->cpu, cr30, cr31);
147 printk("%s ORIG_R28: " RFMT "\n", level, regs->orig_r28);
148
149 if (user) {
150 printk("%s IAOQ[0]: " RFMT "\n", level, regs->iaoq[0]);
151 printk("%s IAOQ[1]: " RFMT "\n", level, regs->iaoq[1]);
152 printk("%s RP(r2): " RFMT "\n", level, regs->gr[2]);
153 } else {
154 printk("%s IAOQ[0]: %pS\n", level, (void *) regs->iaoq[0]);
155 printk("%s IAOQ[1]: %pS\n", level, (void *) regs->iaoq[1]);
156 printk("%s RP(r2): %pS\n", level, (void *) regs->gr[2]);
157
158 parisc_show_stack(current, NULL, regs);
159 }
160 }
161
162
dump_stack(void)163 void dump_stack(void)
164 {
165 show_stack(NULL, NULL);
166 }
167
168 EXPORT_SYMBOL(dump_stack);
169
do_show_stack(struct unwind_frame_info * info)170 static void do_show_stack(struct unwind_frame_info *info)
171 {
172 int i = 1;
173
174 printk(KERN_CRIT "Backtrace:\n");
175 while (i <= 16) {
176 if (unwind_once(info) < 0 || info->ip == 0)
177 break;
178
179 if (__kernel_text_address(info->ip)) {
180 printk(KERN_CRIT " [<" RFMT ">] %pS\n",
181 info->ip, (void *) info->ip);
182 i++;
183 }
184 }
185 printk(KERN_CRIT "\n");
186 }
187
parisc_show_stack(struct task_struct * task,unsigned long * sp,struct pt_regs * regs)188 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
189 struct pt_regs *regs)
190 {
191 struct unwind_frame_info info;
192 struct task_struct *t;
193
194 t = task ? task : current;
195 if (regs) {
196 unwind_frame_init(&info, t, regs);
197 goto show_stack;
198 }
199
200 if (t == current) {
201 unsigned long sp;
202
203 HERE:
204 asm volatile ("copy %%r30, %0" : "=r"(sp));
205 {
206 struct pt_regs r;
207
208 memset(&r, 0, sizeof(struct pt_regs));
209 r.iaoq[0] = (unsigned long)&&HERE;
210 r.gr[2] = (unsigned long)__builtin_return_address(0);
211 r.gr[30] = sp;
212
213 unwind_frame_init(&info, current, &r);
214 }
215 } else {
216 unwind_frame_init_from_blocked_task(&info, t);
217 }
218
219 show_stack:
220 do_show_stack(&info);
221 }
222
show_stack(struct task_struct * t,unsigned long * sp)223 void show_stack(struct task_struct *t, unsigned long *sp)
224 {
225 return parisc_show_stack(t, sp, NULL);
226 }
227
is_valid_bugaddr(unsigned long iaoq)228 int is_valid_bugaddr(unsigned long iaoq)
229 {
230 return 1;
231 }
232
die_if_kernel(char * str,struct pt_regs * regs,long err)233 void die_if_kernel(char *str, struct pt_regs *regs, long err)
234 {
235 if (user_mode(regs)) {
236 if (err == 0)
237 return; /* STFU */
238
239 printk(KERN_CRIT "%s (pid %d): %s (code %ld) at " RFMT "\n",
240 current->comm, task_pid_nr(current), str, err, regs->iaoq[0]);
241 #ifdef PRINT_USER_FAULTS
242 /* XXX for debugging only */
243 show_regs(regs);
244 #endif
245 return;
246 }
247
248 oops_in_progress = 1;
249
250 oops_enter();
251
252 /* Amuse the user in a SPARC fashion */
253 if (err) printk(KERN_CRIT
254 " _______________________________ \n"
255 " < Your System ate a SPARC! Gah! >\n"
256 " ------------------------------- \n"
257 " \\ ^__^\n"
258 " (__)\\ )\\/\\\n"
259 " U ||----w |\n"
260 " || ||\n");
261
262 /* unlock the pdc lock if necessary */
263 pdc_emergency_unlock();
264
265 /* maybe the kernel hasn't booted very far yet and hasn't been able
266 * to initialize the serial or STI console. In that case we should
267 * re-enable the pdc console, so that the user will be able to
268 * identify the problem. */
269 if (!console_drivers)
270 pdc_console_restart();
271
272 if (err)
273 printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n",
274 current->comm, task_pid_nr(current), str, err);
275
276 /* Wot's wrong wif bein' racy? */
277 if (current->thread.flags & PARISC_KERNEL_DEATH) {
278 printk(KERN_CRIT "%s() recursion detected.\n", __func__);
279 local_irq_enable();
280 while (1);
281 }
282 current->thread.flags |= PARISC_KERNEL_DEATH;
283
284 show_regs(regs);
285 dump_stack();
286 add_taint(TAINT_DIE);
287
288 if (in_interrupt())
289 panic("Fatal exception in interrupt");
290
291 if (panic_on_oops) {
292 printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
293 ssleep(5);
294 panic("Fatal exception");
295 }
296
297 oops_exit();
298 do_exit(SIGSEGV);
299 }
300
syscall_ipi(int (* syscall)(struct pt_regs *),struct pt_regs * regs)301 int syscall_ipi(int (*syscall) (struct pt_regs *), struct pt_regs *regs)
302 {
303 return syscall(regs);
304 }
305
306 /* gdb uses break 4,8 */
307 #define GDB_BREAK_INSN 0x10004
handle_gdb_break(struct pt_regs * regs,int wot)308 static void handle_gdb_break(struct pt_regs *regs, int wot)
309 {
310 struct siginfo si;
311
312 si.si_signo = SIGTRAP;
313 si.si_errno = 0;
314 si.si_code = wot;
315 si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
316 force_sig_info(SIGTRAP, &si, current);
317 }
318
handle_break(struct pt_regs * regs)319 static void handle_break(struct pt_regs *regs)
320 {
321 unsigned iir = regs->iir;
322
323 if (unlikely(iir == PARISC_BUG_BREAK_INSN && !user_mode(regs))) {
324 /* check if a BUG() or WARN() trapped here. */
325 enum bug_trap_type tt;
326 tt = report_bug(regs->iaoq[0] & ~3, regs);
327 if (tt == BUG_TRAP_TYPE_WARN) {
328 regs->iaoq[0] += 4;
329 regs->iaoq[1] += 4;
330 return; /* return to next instruction when WARN_ON(). */
331 }
332 die_if_kernel("Unknown kernel breakpoint", regs,
333 (tt == BUG_TRAP_TYPE_NONE) ? 9 : 0);
334 }
335
336 #ifdef PRINT_USER_FAULTS
337 if (unlikely(iir != GDB_BREAK_INSN)) {
338 printk(KERN_DEBUG "break %d,%d: pid=%d command='%s'\n",
339 iir & 31, (iir>>13) & ((1<<13)-1),
340 task_pid_nr(current), current->comm);
341 show_regs(regs);
342 }
343 #endif
344
345 /* send standard GDB signal */
346 handle_gdb_break(regs, TRAP_BRKPT);
347 }
348
default_trap(int code,struct pt_regs * regs)349 static void default_trap(int code, struct pt_regs *regs)
350 {
351 printk(KERN_ERR "Trap %d on CPU %d\n", code, smp_processor_id());
352 show_regs(regs);
353 }
354
355 void (*cpu_lpmc) (int code, struct pt_regs *regs) __read_mostly = default_trap;
356
357
transfer_pim_to_trap_frame(struct pt_regs * regs)358 void transfer_pim_to_trap_frame(struct pt_regs *regs)
359 {
360 register int i;
361 extern unsigned int hpmc_pim_data[];
362 struct pdc_hpmc_pim_11 *pim_narrow;
363 struct pdc_hpmc_pim_20 *pim_wide;
364
365 if (boot_cpu_data.cpu_type >= pcxu) {
366
367 pim_wide = (struct pdc_hpmc_pim_20 *)hpmc_pim_data;
368
369 /*
370 * Note: The following code will probably generate a
371 * bunch of truncation error warnings from the compiler.
372 * Could be handled with an ifdef, but perhaps there
373 * is a better way.
374 */
375
376 regs->gr[0] = pim_wide->cr[22];
377
378 for (i = 1; i < 32; i++)
379 regs->gr[i] = pim_wide->gr[i];
380
381 for (i = 0; i < 32; i++)
382 regs->fr[i] = pim_wide->fr[i];
383
384 for (i = 0; i < 8; i++)
385 regs->sr[i] = pim_wide->sr[i];
386
387 regs->iasq[0] = pim_wide->cr[17];
388 regs->iasq[1] = pim_wide->iasq_back;
389 regs->iaoq[0] = pim_wide->cr[18];
390 regs->iaoq[1] = pim_wide->iaoq_back;
391
392 regs->sar = pim_wide->cr[11];
393 regs->iir = pim_wide->cr[19];
394 regs->isr = pim_wide->cr[20];
395 regs->ior = pim_wide->cr[21];
396 }
397 else {
398 pim_narrow = (struct pdc_hpmc_pim_11 *)hpmc_pim_data;
399
400 regs->gr[0] = pim_narrow->cr[22];
401
402 for (i = 1; i < 32; i++)
403 regs->gr[i] = pim_narrow->gr[i];
404
405 for (i = 0; i < 32; i++)
406 regs->fr[i] = pim_narrow->fr[i];
407
408 for (i = 0; i < 8; i++)
409 regs->sr[i] = pim_narrow->sr[i];
410
411 regs->iasq[0] = pim_narrow->cr[17];
412 regs->iasq[1] = pim_narrow->iasq_back;
413 regs->iaoq[0] = pim_narrow->cr[18];
414 regs->iaoq[1] = pim_narrow->iaoq_back;
415
416 regs->sar = pim_narrow->cr[11];
417 regs->iir = pim_narrow->cr[19];
418 regs->isr = pim_narrow->cr[20];
419 regs->ior = pim_narrow->cr[21];
420 }
421
422 /*
423 * The following fields only have meaning if we came through
424 * another path. So just zero them here.
425 */
426
427 regs->ksp = 0;
428 regs->kpc = 0;
429 regs->orig_r28 = 0;
430 }
431
432
433 /*
434 * This routine is called as a last resort when everything else
435 * has gone clearly wrong. We get called for faults in kernel space,
436 * and HPMC's.
437 */
parisc_terminate(char * msg,struct pt_regs * regs,int code,unsigned long offset)438 void parisc_terminate(char *msg, struct pt_regs *regs, int code, unsigned long offset)
439 {
440 static DEFINE_SPINLOCK(terminate_lock);
441
442 oops_in_progress = 1;
443
444 set_eiem(0);
445 local_irq_disable();
446 spin_lock(&terminate_lock);
447
448 /* unlock the pdc lock if necessary */
449 pdc_emergency_unlock();
450
451 /* restart pdc console if necessary */
452 if (!console_drivers)
453 pdc_console_restart();
454
455 /* Not all paths will gutter the processor... */
456 switch(code){
457
458 case 1:
459 transfer_pim_to_trap_frame(regs);
460 break;
461
462 default:
463 /* Fall through */
464 break;
465
466 }
467
468 {
469 /* show_stack(NULL, (unsigned long *)regs->gr[30]); */
470 struct unwind_frame_info info;
471 unwind_frame_init(&info, current, regs);
472 do_show_stack(&info);
473 }
474
475 printk("\n");
476 printk(KERN_CRIT "%s: Code=%d regs=%p (Addr=" RFMT ")\n",
477 msg, code, regs, offset);
478 show_regs(regs);
479
480 spin_unlock(&terminate_lock);
481
482 /* put soft power button back under hardware control;
483 * if the user had pressed it once at any time, the
484 * system will shut down immediately right here. */
485 pdc_soft_power_button(0);
486
487 /* Call kernel panic() so reboot timeouts work properly
488 * FIXME: This function should be on the list of
489 * panic notifiers, and we should call panic
490 * directly from the location that we wish.
491 * e.g. We should not call panic from
492 * parisc_terminate, but rather the oter way around.
493 * This hack works, prints the panic message twice,
494 * and it enables reboot timers!
495 */
496 panic(msg);
497 }
498
handle_interruption(int code,struct pt_regs * regs)499 void notrace handle_interruption(int code, struct pt_regs *regs)
500 {
501 unsigned long fault_address = 0;
502 unsigned long fault_space = 0;
503 struct siginfo si;
504
505 if (code == 1)
506 pdc_console_restart(); /* switch back to pdc if HPMC */
507 else
508 local_irq_enable();
509
510 /* Security check:
511 * If the priority level is still user, and the
512 * faulting space is not equal to the active space
513 * then the user is attempting something in a space
514 * that does not belong to them. Kill the process.
515 *
516 * This is normally the situation when the user
517 * attempts to jump into the kernel space at the
518 * wrong offset, be it at the gateway page or a
519 * random location.
520 *
521 * We cannot normally signal the process because it
522 * could *be* on the gateway page, and processes
523 * executing on the gateway page can't have signals
524 * delivered.
525 *
526 * We merely readjust the address into the users
527 * space, at a destination address of zero, and
528 * allow processing to continue.
529 */
530 if (((unsigned long)regs->iaoq[0] & 3) &&
531 ((unsigned long)regs->iasq[0] != (unsigned long)regs->sr[7])) {
532 /* Kill the user process later */
533 regs->iaoq[0] = 0 | 3;
534 regs->iaoq[1] = regs->iaoq[0] + 4;
535 regs->iasq[0] = regs->iasq[1] = regs->sr[7];
536 regs->gr[0] &= ~PSW_B;
537 return;
538 }
539
540 #if 0
541 printk(KERN_CRIT "Interruption # %d\n", code);
542 #endif
543
544 switch(code) {
545
546 case 1:
547 /* High-priority machine check (HPMC) */
548
549 /* set up a new led state on systems shipped with a LED State panel */
550 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_HPMC);
551
552 parisc_terminate("High Priority Machine Check (HPMC)",
553 regs, code, 0);
554 /* NOT REACHED */
555
556 case 2:
557 /* Power failure interrupt */
558 printk(KERN_CRIT "Power failure interrupt !\n");
559 return;
560
561 case 3:
562 /* Recovery counter trap */
563 regs->gr[0] &= ~PSW_R;
564 if (user_space(regs))
565 handle_gdb_break(regs, TRAP_TRACE);
566 /* else this must be the start of a syscall - just let it run */
567 return;
568
569 case 5:
570 /* Low-priority machine check */
571 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_LPMC);
572
573 flush_cache_all();
574 flush_tlb_all();
575 cpu_lpmc(5, regs);
576 return;
577
578 case 6:
579 /* Instruction TLB miss fault/Instruction page fault */
580 fault_address = regs->iaoq[0];
581 fault_space = regs->iasq[0];
582 break;
583
584 case 8:
585 /* Illegal instruction trap */
586 die_if_kernel("Illegal instruction", regs, code);
587 si.si_code = ILL_ILLOPC;
588 goto give_sigill;
589
590 case 9:
591 /* Break instruction trap */
592 handle_break(regs);
593 return;
594
595 case 10:
596 /* Privileged operation trap */
597 die_if_kernel("Privileged operation", regs, code);
598 si.si_code = ILL_PRVOPC;
599 goto give_sigill;
600
601 case 11:
602 /* Privileged register trap */
603 if ((regs->iir & 0xffdfffe0) == 0x034008a0) {
604
605 /* This is a MFCTL cr26/cr27 to gr instruction.
606 * PCXS traps on this, so we need to emulate it.
607 */
608
609 if (regs->iir & 0x00200000)
610 regs->gr[regs->iir & 0x1f] = mfctl(27);
611 else
612 regs->gr[regs->iir & 0x1f] = mfctl(26);
613
614 regs->iaoq[0] = regs->iaoq[1];
615 regs->iaoq[1] += 4;
616 regs->iasq[0] = regs->iasq[1];
617 return;
618 }
619
620 die_if_kernel("Privileged register usage", regs, code);
621 si.si_code = ILL_PRVREG;
622 give_sigill:
623 si.si_signo = SIGILL;
624 si.si_errno = 0;
625 si.si_addr = (void __user *) regs->iaoq[0];
626 force_sig_info(SIGILL, &si, current);
627 return;
628
629 case 12:
630 /* Overflow Trap, let the userland signal handler do the cleanup */
631 si.si_signo = SIGFPE;
632 si.si_code = FPE_INTOVF;
633 si.si_addr = (void __user *) regs->iaoq[0];
634 force_sig_info(SIGFPE, &si, current);
635 return;
636
637 case 13:
638 /* Conditional Trap
639 The condition succeeds in an instruction which traps
640 on condition */
641 if(user_mode(regs)){
642 si.si_signo = SIGFPE;
643 /* Set to zero, and let the userspace app figure it out from
644 the insn pointed to by si_addr */
645 si.si_code = 0;
646 si.si_addr = (void __user *) regs->iaoq[0];
647 force_sig_info(SIGFPE, &si, current);
648 return;
649 }
650 /* The kernel doesn't want to handle condition codes */
651 break;
652
653 case 14:
654 /* Assist Exception Trap, i.e. floating point exception. */
655 die_if_kernel("Floating point exception", regs, 0); /* quiet */
656 handle_fpe(regs);
657 return;
658
659 case 15:
660 /* Data TLB miss fault/Data page fault */
661 /* Fall through */
662 case 16:
663 /* Non-access instruction TLB miss fault */
664 /* The instruction TLB entry needed for the target address of the FIC
665 is absent, and hardware can't find it, so we get to cleanup */
666 /* Fall through */
667 case 17:
668 /* Non-access data TLB miss fault/Non-access data page fault */
669 /* FIXME:
670 Still need to add slow path emulation code here!
671 If the insn used a non-shadow register, then the tlb
672 handlers could not have their side-effect (e.g. probe
673 writing to a target register) emulated since rfir would
674 erase the changes to said register. Instead we have to
675 setup everything, call this function we are in, and emulate
676 by hand. Technically we need to emulate:
677 fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw
678 */
679 fault_address = regs->ior;
680 fault_space = regs->isr;
681 break;
682
683 case 18:
684 /* PCXS only -- later cpu's split this into types 26,27 & 28 */
685 /* Check for unaligned access */
686 if (check_unaligned(regs)) {
687 handle_unaligned(regs);
688 return;
689 }
690 /* Fall Through */
691 case 26:
692 /* PCXL: Data memory access rights trap */
693 fault_address = regs->ior;
694 fault_space = regs->isr;
695 break;
696
697 case 19:
698 /* Data memory break trap */
699 regs->gr[0] |= PSW_X; /* So we can single-step over the trap */
700 /* fall thru */
701 case 21:
702 /* Page reference trap */
703 handle_gdb_break(regs, TRAP_HWBKPT);
704 return;
705
706 case 25:
707 /* Taken branch trap */
708 regs->gr[0] &= ~PSW_T;
709 if (user_space(regs))
710 handle_gdb_break(regs, TRAP_BRANCH);
711 /* else this must be the start of a syscall - just let it
712 * run.
713 */
714 return;
715
716 case 7:
717 /* Instruction access rights */
718 /* PCXL: Instruction memory protection trap */
719
720 /*
721 * This could be caused by either: 1) a process attempting
722 * to execute within a vma that does not have execute
723 * permission, or 2) an access rights violation caused by a
724 * flush only translation set up by ptep_get_and_clear().
725 * So we check the vma permissions to differentiate the two.
726 * If the vma indicates we have execute permission, then
727 * the cause is the latter one. In this case, we need to
728 * call do_page_fault() to fix the problem.
729 */
730
731 if (user_mode(regs)) {
732 struct vm_area_struct *vma;
733
734 down_read(¤t->mm->mmap_sem);
735 vma = find_vma(current->mm,regs->iaoq[0]);
736 if (vma && (regs->iaoq[0] >= vma->vm_start)
737 && (vma->vm_flags & VM_EXEC)) {
738
739 fault_address = regs->iaoq[0];
740 fault_space = regs->iasq[0];
741
742 up_read(¤t->mm->mmap_sem);
743 break; /* call do_page_fault() */
744 }
745 up_read(¤t->mm->mmap_sem);
746 }
747 /* Fall Through */
748 case 27:
749 /* Data memory protection ID trap */
750 if (code == 27 && !user_mode(regs) &&
751 fixup_exception(regs))
752 return;
753
754 die_if_kernel("Protection id trap", regs, code);
755 si.si_code = SEGV_MAPERR;
756 si.si_signo = SIGSEGV;
757 si.si_errno = 0;
758 if (code == 7)
759 si.si_addr = (void __user *) regs->iaoq[0];
760 else
761 si.si_addr = (void __user *) regs->ior;
762 force_sig_info(SIGSEGV, &si, current);
763 return;
764
765 case 28:
766 /* Unaligned data reference trap */
767 handle_unaligned(regs);
768 return;
769
770 default:
771 if (user_mode(regs)) {
772 #ifdef PRINT_USER_FAULTS
773 printk(KERN_DEBUG "\nhandle_interruption() pid=%d command='%s'\n",
774 task_pid_nr(current), current->comm);
775 show_regs(regs);
776 #endif
777 /* SIGBUS, for lack of a better one. */
778 si.si_signo = SIGBUS;
779 si.si_code = BUS_OBJERR;
780 si.si_errno = 0;
781 si.si_addr = (void __user *) regs->ior;
782 force_sig_info(SIGBUS, &si, current);
783 return;
784 }
785 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC);
786
787 parisc_terminate("Unexpected interruption", regs, code, 0);
788 /* NOT REACHED */
789 }
790
791 if (user_mode(regs)) {
792 if ((fault_space >> SPACEID_SHIFT) != (regs->sr[7] >> SPACEID_SHIFT)) {
793 #ifdef PRINT_USER_FAULTS
794 if (fault_space == 0)
795 printk(KERN_DEBUG "User Fault on Kernel Space ");
796 else
797 printk(KERN_DEBUG "User Fault (long pointer) (fault %d) ",
798 code);
799 printk(KERN_CONT "pid=%d command='%s'\n",
800 task_pid_nr(current), current->comm);
801 show_regs(regs);
802 #endif
803 si.si_signo = SIGSEGV;
804 si.si_errno = 0;
805 si.si_code = SEGV_MAPERR;
806 si.si_addr = (void __user *) regs->ior;
807 force_sig_info(SIGSEGV, &si, current);
808 return;
809 }
810 }
811 else {
812
813 /*
814 * The kernel should never fault on its own address space.
815 */
816
817 if (fault_space == 0)
818 {
819 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC);
820 parisc_terminate("Kernel Fault", regs, code, fault_address);
821
822 }
823 }
824
825 do_page_fault(regs, code, fault_address);
826 }
827
828
check_ivt(void * iva)829 int __init check_ivt(void *iva)
830 {
831 extern u32 os_hpmc_size;
832 extern const u32 os_hpmc[];
833
834 int i;
835 u32 check = 0;
836 u32 *ivap;
837 u32 *hpmcp;
838 u32 length;
839
840 if (strcmp((char *)iva, "cows can fly"))
841 return -1;
842
843 ivap = (u32 *)iva;
844
845 for (i = 0; i < 8; i++)
846 *ivap++ = 0;
847
848 /* Compute Checksum for HPMC handler */
849 length = os_hpmc_size;
850 ivap[7] = length;
851
852 hpmcp = (u32 *)os_hpmc;
853
854 for (i=0; i<length/4; i++)
855 check += *hpmcp++;
856
857 for (i=0; i<8; i++)
858 check += ivap[i];
859
860 ivap[5] = -check;
861
862 return 0;
863 }
864
865 #ifndef CONFIG_64BIT
866 extern const void fault_vector_11;
867 #endif
868 extern const void fault_vector_20;
869
trap_init(void)870 void __init trap_init(void)
871 {
872 void *iva;
873
874 if (boot_cpu_data.cpu_type >= pcxu)
875 iva = (void *) &fault_vector_20;
876 else
877 #ifdef CONFIG_64BIT
878 panic("Can't boot 64-bit OS on PA1.1 processor!");
879 #else
880 iva = (void *) &fault_vector_11;
881 #endif
882
883 if (check_ivt(iva))
884 panic("IVT invalid");
885 }
886