1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/arch/parisc/traps.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * Copyright (C) 1999, 2000 Philipp Rumpf <prumpf@tux.org> 7 */ 8 9 /* 10 * 'Traps.c' handles hardware traps and faults after we have saved some 11 * state in 'asm.s'. 12 */ 13 14 #include <linux/sched.h> 15 #include <linux/sched/debug.h> 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <linux/errno.h> 19 #include <linux/ptrace.h> 20 #include <linux/timer.h> 21 #include <linux/delay.h> 22 #include <linux/mm.h> 23 #include <linux/module.h> 24 #include <linux/smp.h> 25 #include <linux/spinlock.h> 26 #include <linux/init.h> 27 #include <linux/interrupt.h> 28 #include <linux/console.h> 29 #include <linux/bug.h> 30 #include <linux/ratelimit.h> 31 #include <linux/uaccess.h> 32 #include <linux/kdebug.h> 33 34 #include <asm/assembly.h> 35 #include <asm/io.h> 36 #include <asm/irq.h> 37 #include <asm/traps.h> 38 #include <asm/unaligned.h> 39 #include <linux/atomic.h> 40 #include <asm/smp.h> 41 #include <asm/pdc.h> 42 #include <asm/pdc_chassis.h> 43 #include <asm/unwind.h> 44 #include <asm/tlbflush.h> 45 #include <asm/cacheflush.h> 46 #include <linux/kgdb.h> 47 #include <linux/kprobes.h> 48 49 #include "../math-emu/math-emu.h" /* for handle_fpe() */ 50 51 static void parisc_show_stack(struct task_struct *task, 52 struct pt_regs *regs, const char *loglvl); 53 54 static int printbinary(char *buf, unsigned long x, int nbits) 55 { 56 unsigned long mask = 1UL << (nbits - 1); 57 while (mask != 0) { 58 *buf++ = (mask & x ? '1' : '0'); 59 mask >>= 1; 60 } 61 *buf = '\0'; 62 63 return nbits; 64 } 65 66 #ifdef CONFIG_64BIT 67 #define RFMT "%016lx" 68 #else 69 #define RFMT "%08lx" 70 #endif 71 #define FFMT "%016llx" /* fpregs are 64-bit always */ 72 73 #define PRINTREGS(lvl,r,f,fmt,x) \ 74 printk("%s%s%02d-%02d " fmt " " fmt " " fmt " " fmt "\n", \ 75 lvl, f, (x), (x+3), (r)[(x)+0], (r)[(x)+1], \ 76 (r)[(x)+2], (r)[(x)+3]) 77 78 static void print_gr(char *level, struct pt_regs *regs) 79 { 80 int i; 81 char buf[64]; 82 83 printk("%s\n", level); 84 printk("%s YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI\n", level); 85 printbinary(buf, regs->gr[0], 32); 86 printk("%sPSW: %s %s\n", level, buf, print_tainted()); 87 88 for (i = 0; i < 32; i += 4) 89 PRINTREGS(level, regs->gr, "r", RFMT, i); 90 } 91 92 static void print_fr(char *level, struct pt_regs *regs) 93 { 94 int i; 95 char buf[64]; 96 struct { u32 sw[2]; } s; 97 98 /* FR are 64bit everywhere. Need to use asm to get the content 99 * of fpsr/fper1, and we assume that we won't have a FP Identify 100 * in our way, otherwise we're screwed. 101 * The fldd is used to restore the T-bit if there was one, as the 102 * store clears it anyway. 103 * PA2.0 book says "thou shall not use fstw on FPSR/FPERs" - T-Bone */ 104 asm volatile ("fstd %%fr0,0(%1) \n\t" 105 "fldd 0(%1),%%fr0 \n\t" 106 : "=m" (s) : "r" (&s) : "r0"); 107 108 printk("%s\n", level); 109 printk("%s VZOUICununcqcqcqcqcqcrmunTDVZOUI\n", level); 110 printbinary(buf, s.sw[0], 32); 111 printk("%sFPSR: %s\n", level, buf); 112 printk("%sFPER1: %08x\n", level, s.sw[1]); 113 114 /* here we'll print fr0 again, tho it'll be meaningless */ 115 for (i = 0; i < 32; i += 4) 116 PRINTREGS(level, regs->fr, "fr", FFMT, i); 117 } 118 119 void show_regs(struct pt_regs *regs) 120 { 121 int i, user; 122 char *level; 123 unsigned long cr30, cr31; 124 125 user = user_mode(regs); 126 level = user ? KERN_DEBUG : KERN_CRIT; 127 128 show_regs_print_info(level); 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, regs, KERN_DEFAULT); 159 } 160 } 161 162 static DEFINE_RATELIMIT_STATE(_hppa_rs, 163 DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); 164 165 #define parisc_printk_ratelimited(critical, regs, fmt, ...) { \ 166 if ((critical || show_unhandled_signals) && __ratelimit(&_hppa_rs)) { \ 167 printk(fmt, ##__VA_ARGS__); \ 168 show_regs(regs); \ 169 } \ 170 } 171 172 173 static void do_show_stack(struct unwind_frame_info *info, const char *loglvl) 174 { 175 int i = 1; 176 177 printk("%sBacktrace:\n", loglvl); 178 while (i <= MAX_UNWIND_ENTRIES) { 179 if (unwind_once(info) < 0 || info->ip == 0) 180 break; 181 182 if (__kernel_text_address(info->ip)) { 183 printk("%s [<" RFMT ">] %pS\n", 184 loglvl, info->ip, (void *) info->ip); 185 i++; 186 } 187 } 188 printk("%s\n", loglvl); 189 } 190 191 static void parisc_show_stack(struct task_struct *task, 192 struct pt_regs *regs, const char *loglvl) 193 { 194 struct unwind_frame_info info; 195 196 unwind_frame_init_task(&info, task, regs); 197 198 do_show_stack(&info, loglvl); 199 } 200 201 void show_stack(struct task_struct *t, unsigned long *sp, const char *loglvl) 202 { 203 parisc_show_stack(t, NULL, loglvl); 204 } 205 206 int is_valid_bugaddr(unsigned long iaoq) 207 { 208 return 1; 209 } 210 211 void die_if_kernel(char *str, struct pt_regs *regs, long err) 212 { 213 if (user_mode(regs)) { 214 if (err == 0) 215 return; /* STFU */ 216 217 parisc_printk_ratelimited(1, regs, 218 KERN_CRIT "%s (pid %d): %s (code %ld) at " RFMT "\n", 219 current->comm, task_pid_nr(current), str, err, regs->iaoq[0]); 220 221 return; 222 } 223 224 bust_spinlocks(1); 225 226 oops_enter(); 227 228 /* Amuse the user in a SPARC fashion */ 229 if (err) printk(KERN_CRIT 230 " _______________________________ \n" 231 " < Your System ate a SPARC! Gah! >\n" 232 " ------------------------------- \n" 233 " \\ ^__^\n" 234 " (__)\\ )\\/\\\n" 235 " U ||----w |\n" 236 " || ||\n"); 237 238 /* unlock the pdc lock if necessary */ 239 pdc_emergency_unlock(); 240 241 /* maybe the kernel hasn't booted very far yet and hasn't been able 242 * to initialize the serial or STI console. In that case we should 243 * re-enable the pdc console, so that the user will be able to 244 * identify the problem. */ 245 if (!console_drivers) 246 pdc_console_restart(); 247 248 if (err) 249 printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n", 250 current->comm, task_pid_nr(current), str, err); 251 252 /* Wot's wrong wif bein' racy? */ 253 if (current->thread.flags & PARISC_KERNEL_DEATH) { 254 printk(KERN_CRIT "%s() recursion detected.\n", __func__); 255 local_irq_enable(); 256 while (1); 257 } 258 current->thread.flags |= PARISC_KERNEL_DEATH; 259 260 show_regs(regs); 261 dump_stack(); 262 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); 263 264 if (in_interrupt()) 265 panic("Fatal exception in interrupt"); 266 267 if (panic_on_oops) 268 panic("Fatal exception"); 269 270 oops_exit(); 271 do_exit(SIGSEGV); 272 } 273 274 /* gdb uses break 4,8 */ 275 #define GDB_BREAK_INSN 0x10004 276 static void handle_gdb_break(struct pt_regs *regs, int wot) 277 { 278 force_sig_fault(SIGTRAP, wot, 279 (void __user *) (regs->iaoq[0] & ~3)); 280 } 281 282 static void handle_break(struct pt_regs *regs) 283 { 284 unsigned iir = regs->iir; 285 286 if (unlikely(iir == PARISC_BUG_BREAK_INSN && !user_mode(regs))) { 287 /* check if a BUG() or WARN() trapped here. */ 288 enum bug_trap_type tt; 289 tt = report_bug(regs->iaoq[0] & ~3, regs); 290 if (tt == BUG_TRAP_TYPE_WARN) { 291 regs->iaoq[0] += 4; 292 regs->iaoq[1] += 4; 293 return; /* return to next instruction when WARN_ON(). */ 294 } 295 die_if_kernel("Unknown kernel breakpoint", regs, 296 (tt == BUG_TRAP_TYPE_NONE) ? 9 : 0); 297 } 298 299 #ifdef CONFIG_KPROBES 300 if (unlikely(iir == PARISC_KPROBES_BREAK_INSN)) { 301 parisc_kprobe_break_handler(regs); 302 return; 303 } 304 305 #endif 306 307 #ifdef CONFIG_KGDB 308 if (unlikely(iir == PARISC_KGDB_COMPILED_BREAK_INSN || 309 iir == PARISC_KGDB_BREAK_INSN)) { 310 kgdb_handle_exception(9, SIGTRAP, 0, regs); 311 return; 312 } 313 #endif 314 315 if (unlikely(iir != GDB_BREAK_INSN)) 316 parisc_printk_ratelimited(0, regs, 317 KERN_DEBUG "break %d,%d: pid=%d command='%s'\n", 318 iir & 31, (iir>>13) & ((1<<13)-1), 319 task_pid_nr(current), current->comm); 320 321 /* send standard GDB signal */ 322 handle_gdb_break(regs, TRAP_BRKPT); 323 } 324 325 static void default_trap(int code, struct pt_regs *regs) 326 { 327 printk(KERN_ERR "Trap %d on CPU %d\n", code, smp_processor_id()); 328 show_regs(regs); 329 } 330 331 void (*cpu_lpmc) (int code, struct pt_regs *regs) __read_mostly = default_trap; 332 333 334 void transfer_pim_to_trap_frame(struct pt_regs *regs) 335 { 336 register int i; 337 extern unsigned int hpmc_pim_data[]; 338 struct pdc_hpmc_pim_11 *pim_narrow; 339 struct pdc_hpmc_pim_20 *pim_wide; 340 341 if (boot_cpu_data.cpu_type >= pcxu) { 342 343 pim_wide = (struct pdc_hpmc_pim_20 *)hpmc_pim_data; 344 345 /* 346 * Note: The following code will probably generate a 347 * bunch of truncation error warnings from the compiler. 348 * Could be handled with an ifdef, but perhaps there 349 * is a better way. 350 */ 351 352 regs->gr[0] = pim_wide->cr[22]; 353 354 for (i = 1; i < 32; i++) 355 regs->gr[i] = pim_wide->gr[i]; 356 357 for (i = 0; i < 32; i++) 358 regs->fr[i] = pim_wide->fr[i]; 359 360 for (i = 0; i < 8; i++) 361 regs->sr[i] = pim_wide->sr[i]; 362 363 regs->iasq[0] = pim_wide->cr[17]; 364 regs->iasq[1] = pim_wide->iasq_back; 365 regs->iaoq[0] = pim_wide->cr[18]; 366 regs->iaoq[1] = pim_wide->iaoq_back; 367 368 regs->sar = pim_wide->cr[11]; 369 regs->iir = pim_wide->cr[19]; 370 regs->isr = pim_wide->cr[20]; 371 regs->ior = pim_wide->cr[21]; 372 } 373 else { 374 pim_narrow = (struct pdc_hpmc_pim_11 *)hpmc_pim_data; 375 376 regs->gr[0] = pim_narrow->cr[22]; 377 378 for (i = 1; i < 32; i++) 379 regs->gr[i] = pim_narrow->gr[i]; 380 381 for (i = 0; i < 32; i++) 382 regs->fr[i] = pim_narrow->fr[i]; 383 384 for (i = 0; i < 8; i++) 385 regs->sr[i] = pim_narrow->sr[i]; 386 387 regs->iasq[0] = pim_narrow->cr[17]; 388 regs->iasq[1] = pim_narrow->iasq_back; 389 regs->iaoq[0] = pim_narrow->cr[18]; 390 regs->iaoq[1] = pim_narrow->iaoq_back; 391 392 regs->sar = pim_narrow->cr[11]; 393 regs->iir = pim_narrow->cr[19]; 394 regs->isr = pim_narrow->cr[20]; 395 regs->ior = pim_narrow->cr[21]; 396 } 397 398 /* 399 * The following fields only have meaning if we came through 400 * another path. So just zero them here. 401 */ 402 403 regs->ksp = 0; 404 regs->kpc = 0; 405 regs->orig_r28 = 0; 406 } 407 408 409 /* 410 * This routine is called as a last resort when everything else 411 * has gone clearly wrong. We get called for faults in kernel space, 412 * and HPMC's. 413 */ 414 void parisc_terminate(char *msg, struct pt_regs *regs, int code, unsigned long offset) 415 { 416 static DEFINE_SPINLOCK(terminate_lock); 417 418 (void)notify_die(DIE_OOPS, msg, regs, 0, code, SIGTRAP); 419 bust_spinlocks(1); 420 421 set_eiem(0); 422 local_irq_disable(); 423 spin_lock(&terminate_lock); 424 425 /* unlock the pdc lock if necessary */ 426 pdc_emergency_unlock(); 427 428 /* restart pdc console if necessary */ 429 if (!console_drivers) 430 pdc_console_restart(); 431 432 /* Not all paths will gutter the processor... */ 433 switch(code){ 434 435 case 1: 436 transfer_pim_to_trap_frame(regs); 437 break; 438 439 default: 440 /* Fall through */ 441 break; 442 443 } 444 445 { 446 /* show_stack(NULL, (unsigned long *)regs->gr[30]); */ 447 struct unwind_frame_info info; 448 unwind_frame_init(&info, current, regs); 449 do_show_stack(&info, KERN_CRIT); 450 } 451 452 printk("\n"); 453 pr_crit("%s: Code=%d (%s) at addr " RFMT "\n", 454 msg, code, trap_name(code), offset); 455 show_regs(regs); 456 457 spin_unlock(&terminate_lock); 458 459 /* put soft power button back under hardware control; 460 * if the user had pressed it once at any time, the 461 * system will shut down immediately right here. */ 462 pdc_soft_power_button(0); 463 464 /* Call kernel panic() so reboot timeouts work properly 465 * FIXME: This function should be on the list of 466 * panic notifiers, and we should call panic 467 * directly from the location that we wish. 468 * e.g. We should not call panic from 469 * parisc_terminate, but rather the oter way around. 470 * This hack works, prints the panic message twice, 471 * and it enables reboot timers! 472 */ 473 panic(msg); 474 } 475 476 void notrace handle_interruption(int code, struct pt_regs *regs) 477 { 478 unsigned long fault_address = 0; 479 unsigned long fault_space = 0; 480 int si_code; 481 482 if (code == 1) 483 pdc_console_restart(); /* switch back to pdc if HPMC */ 484 else 485 local_irq_enable(); 486 487 /* Security check: 488 * If the priority level is still user, and the 489 * faulting space is not equal to the active space 490 * then the user is attempting something in a space 491 * that does not belong to them. Kill the process. 492 * 493 * This is normally the situation when the user 494 * attempts to jump into the kernel space at the 495 * wrong offset, be it at the gateway page or a 496 * random location. 497 * 498 * We cannot normally signal the process because it 499 * could *be* on the gateway page, and processes 500 * executing on the gateway page can't have signals 501 * delivered. 502 * 503 * We merely readjust the address into the users 504 * space, at a destination address of zero, and 505 * allow processing to continue. 506 */ 507 if (((unsigned long)regs->iaoq[0] & 3) && 508 ((unsigned long)regs->iasq[0] != (unsigned long)regs->sr[7])) { 509 /* Kill the user process later */ 510 regs->iaoq[0] = 0 | 3; 511 regs->iaoq[1] = regs->iaoq[0] + 4; 512 regs->iasq[0] = regs->iasq[1] = regs->sr[7]; 513 regs->gr[0] &= ~PSW_B; 514 return; 515 } 516 517 #if 0 518 printk(KERN_CRIT "Interruption # %d\n", code); 519 #endif 520 521 switch(code) { 522 523 case 1: 524 /* High-priority machine check (HPMC) */ 525 526 /* set up a new led state on systems shipped with a LED State panel */ 527 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_HPMC); 528 529 parisc_terminate("High Priority Machine Check (HPMC)", 530 regs, code, 0); 531 /* NOT REACHED */ 532 533 case 2: 534 /* Power failure interrupt */ 535 printk(KERN_CRIT "Power failure interrupt !\n"); 536 return; 537 538 case 3: 539 /* Recovery counter trap */ 540 regs->gr[0] &= ~PSW_R; 541 542 #ifdef CONFIG_KPROBES 543 if (parisc_kprobe_ss_handler(regs)) 544 return; 545 #endif 546 547 #ifdef CONFIG_KGDB 548 if (kgdb_single_step) { 549 kgdb_handle_exception(0, SIGTRAP, 0, regs); 550 return; 551 } 552 #endif 553 554 if (user_space(regs)) 555 handle_gdb_break(regs, TRAP_TRACE); 556 /* else this must be the start of a syscall - just let it run */ 557 return; 558 559 case 5: 560 /* Low-priority machine check */ 561 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_LPMC); 562 563 flush_cache_all(); 564 flush_tlb_all(); 565 cpu_lpmc(5, regs); 566 return; 567 568 case PARISC_ITLB_TRAP: 569 /* Instruction TLB miss fault/Instruction page fault */ 570 fault_address = regs->iaoq[0]; 571 fault_space = regs->iasq[0]; 572 break; 573 574 case 8: 575 /* Illegal instruction trap */ 576 die_if_kernel("Illegal instruction", regs, code); 577 si_code = ILL_ILLOPC; 578 goto give_sigill; 579 580 case 9: 581 /* Break instruction trap */ 582 handle_break(regs); 583 return; 584 585 case 10: 586 /* Privileged operation trap */ 587 die_if_kernel("Privileged operation", regs, code); 588 si_code = ILL_PRVOPC; 589 goto give_sigill; 590 591 case 11: 592 /* Privileged register trap */ 593 if ((regs->iir & 0xffdfffe0) == 0x034008a0) { 594 595 /* This is a MFCTL cr26/cr27 to gr instruction. 596 * PCXS traps on this, so we need to emulate it. 597 */ 598 599 if (regs->iir & 0x00200000) 600 regs->gr[regs->iir & 0x1f] = mfctl(27); 601 else 602 regs->gr[regs->iir & 0x1f] = mfctl(26); 603 604 regs->iaoq[0] = regs->iaoq[1]; 605 regs->iaoq[1] += 4; 606 regs->iasq[0] = regs->iasq[1]; 607 return; 608 } 609 610 die_if_kernel("Privileged register usage", regs, code); 611 si_code = ILL_PRVREG; 612 give_sigill: 613 force_sig_fault(SIGILL, si_code, 614 (void __user *) regs->iaoq[0]); 615 return; 616 617 case 12: 618 /* Overflow Trap, let the userland signal handler do the cleanup */ 619 force_sig_fault(SIGFPE, FPE_INTOVF, 620 (void __user *) regs->iaoq[0]); 621 return; 622 623 case 13: 624 /* Conditional Trap 625 The condition succeeds in an instruction which traps 626 on condition */ 627 if(user_mode(regs)){ 628 /* Let userspace app figure it out from the insn pointed 629 * to by si_addr. 630 */ 631 force_sig_fault(SIGFPE, FPE_CONDTRAP, 632 (void __user *) regs->iaoq[0]); 633 return; 634 } 635 /* The kernel doesn't want to handle condition codes */ 636 break; 637 638 case 14: 639 /* Assist Exception Trap, i.e. floating point exception. */ 640 die_if_kernel("Floating point exception", regs, 0); /* quiet */ 641 __inc_irq_stat(irq_fpassist_count); 642 handle_fpe(regs); 643 return; 644 645 case 15: 646 /* Data TLB miss fault/Data page fault */ 647 /* Fall through */ 648 case 16: 649 /* Non-access instruction TLB miss fault */ 650 /* The instruction TLB entry needed for the target address of the FIC 651 is absent, and hardware can't find it, so we get to cleanup */ 652 /* Fall through */ 653 case 17: 654 /* Non-access data TLB miss fault/Non-access data page fault */ 655 /* FIXME: 656 Still need to add slow path emulation code here! 657 If the insn used a non-shadow register, then the tlb 658 handlers could not have their side-effect (e.g. probe 659 writing to a target register) emulated since rfir would 660 erase the changes to said register. Instead we have to 661 setup everything, call this function we are in, and emulate 662 by hand. Technically we need to emulate: 663 fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw 664 */ 665 fault_address = regs->ior; 666 fault_space = regs->isr; 667 break; 668 669 case 18: 670 /* PCXS only -- later cpu's split this into types 26,27 & 28 */ 671 /* Check for unaligned access */ 672 if (check_unaligned(regs)) { 673 handle_unaligned(regs); 674 return; 675 } 676 /* Fall Through */ 677 case 26: 678 /* PCXL: Data memory access rights trap */ 679 fault_address = regs->ior; 680 fault_space = regs->isr; 681 break; 682 683 case 19: 684 /* Data memory break trap */ 685 regs->gr[0] |= PSW_X; /* So we can single-step over the trap */ 686 /* fall thru */ 687 case 21: 688 /* Page reference trap */ 689 handle_gdb_break(regs, TRAP_HWBKPT); 690 return; 691 692 case 25: 693 /* Taken branch trap */ 694 regs->gr[0] &= ~PSW_T; 695 if (user_space(regs)) 696 handle_gdb_break(regs, TRAP_BRANCH); 697 /* else this must be the start of a syscall - just let it 698 * run. 699 */ 700 return; 701 702 case 7: 703 /* Instruction access rights */ 704 /* PCXL: Instruction memory protection trap */ 705 706 /* 707 * This could be caused by either: 1) a process attempting 708 * to execute within a vma that does not have execute 709 * permission, or 2) an access rights violation caused by a 710 * flush only translation set up by ptep_get_and_clear(). 711 * So we check the vma permissions to differentiate the two. 712 * If the vma indicates we have execute permission, then 713 * the cause is the latter one. In this case, we need to 714 * call do_page_fault() to fix the problem. 715 */ 716 717 if (user_mode(regs)) { 718 struct vm_area_struct *vma; 719 720 mmap_read_lock(current->mm); 721 vma = find_vma(current->mm,regs->iaoq[0]); 722 if (vma && (regs->iaoq[0] >= vma->vm_start) 723 && (vma->vm_flags & VM_EXEC)) { 724 725 fault_address = regs->iaoq[0]; 726 fault_space = regs->iasq[0]; 727 728 mmap_read_unlock(current->mm); 729 break; /* call do_page_fault() */ 730 } 731 mmap_read_unlock(current->mm); 732 } 733 /* Fall Through */ 734 case 27: 735 /* Data memory protection ID trap */ 736 if (code == 27 && !user_mode(regs) && 737 fixup_exception(regs)) 738 return; 739 740 die_if_kernel("Protection id trap", regs, code); 741 force_sig_fault(SIGSEGV, SEGV_MAPERR, 742 (code == 7)? 743 ((void __user *) regs->iaoq[0]) : 744 ((void __user *) regs->ior)); 745 return; 746 747 case 28: 748 /* Unaligned data reference trap */ 749 handle_unaligned(regs); 750 return; 751 752 default: 753 if (user_mode(regs)) { 754 parisc_printk_ratelimited(0, regs, KERN_DEBUG 755 "handle_interruption() pid=%d command='%s'\n", 756 task_pid_nr(current), current->comm); 757 /* SIGBUS, for lack of a better one. */ 758 force_sig_fault(SIGBUS, BUS_OBJERR, 759 (void __user *)regs->ior); 760 return; 761 } 762 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC); 763 764 parisc_terminate("Unexpected interruption", regs, code, 0); 765 /* NOT REACHED */ 766 } 767 768 if (user_mode(regs)) { 769 if ((fault_space >> SPACEID_SHIFT) != (regs->sr[7] >> SPACEID_SHIFT)) { 770 parisc_printk_ratelimited(0, regs, KERN_DEBUG 771 "User fault %d on space 0x%08lx, pid=%d command='%s'\n", 772 code, fault_space, 773 task_pid_nr(current), current->comm); 774 force_sig_fault(SIGSEGV, SEGV_MAPERR, 775 (void __user *)regs->ior); 776 return; 777 } 778 } 779 else { 780 781 /* 782 * The kernel should never fault on its own address space, 783 * unless pagefault_disable() was called before. 784 */ 785 786 if (fault_space == 0 && !faulthandler_disabled()) 787 { 788 /* Clean up and return if in exception table. */ 789 if (fixup_exception(regs)) 790 return; 791 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC); 792 parisc_terminate("Kernel Fault", regs, code, fault_address); 793 } 794 } 795 796 do_page_fault(regs, code, fault_address); 797 } 798 799 800 void __init initialize_ivt(const void *iva) 801 { 802 extern u32 os_hpmc_size; 803 extern const u32 os_hpmc[]; 804 805 int i; 806 u32 check = 0; 807 u32 *ivap; 808 u32 *hpmcp; 809 u32 length, instr; 810 811 if (strcmp((const char *)iva, "cows can fly")) 812 panic("IVT invalid"); 813 814 ivap = (u32 *)iva; 815 816 for (i = 0; i < 8; i++) 817 *ivap++ = 0; 818 819 /* 820 * Use PDC_INSTR firmware function to get instruction that invokes 821 * PDCE_CHECK in HPMC handler. See programming note at page 1-31 of 822 * the PA 1.1 Firmware Architecture document. 823 */ 824 if (pdc_instr(&instr) == PDC_OK) 825 ivap[0] = instr; 826 827 /* 828 * Rules for the checksum of the HPMC handler: 829 * 1. The IVA does not point to PDC/PDH space (ie: the OS has installed 830 * its own IVA). 831 * 2. The word at IVA + 32 is nonzero. 832 * 3. If Length (IVA + 60) is not zero, then Length (IVA + 60) and 833 * Address (IVA + 56) are word-aligned. 834 * 4. The checksum of the 8 words starting at IVA + 32 plus the sum of 835 * the Length/4 words starting at Address is zero. 836 */ 837 838 /* Setup IVA and compute checksum for HPMC handler */ 839 ivap[6] = (u32)__pa(os_hpmc); 840 length = os_hpmc_size; 841 ivap[7] = length; 842 843 hpmcp = (u32 *)os_hpmc; 844 845 for (i=0; i<length/4; i++) 846 check += *hpmcp++; 847 848 for (i=0; i<8; i++) 849 check += ivap[i]; 850 851 ivap[5] = -check; 852 } 853 854 855 /* early_trap_init() is called before we set up kernel mappings and 856 * write-protect the kernel */ 857 void __init early_trap_init(void) 858 { 859 extern const void fault_vector_20; 860 861 #ifndef CONFIG_64BIT 862 extern const void fault_vector_11; 863 initialize_ivt(&fault_vector_11); 864 #endif 865 866 initialize_ivt(&fault_vector_20); 867 } 868 869 void __init trap_init(void) 870 { 871 } 872