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 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 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 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 } 120 121 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 } 161 162 163 void dump_stack(void) 164 { 165 show_stack(NULL, NULL); 166 } 167 168 EXPORT_SYMBOL(dump_stack); 169 170 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 } 187 188 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 } 222 223 void show_stack(struct task_struct *t, unsigned long *sp) 224 { 225 return parisc_show_stack(t, sp, NULL); 226 } 227 228 int is_valid_bugaddr(unsigned long iaoq) 229 { 230 return 1; 231 } 232 233 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 } 300 301 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 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 } 318 319 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 } 348 349 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; 356 357 358 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 */ 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 } 498 499 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 } 827 828 829 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; 869 870 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