1 /* 2 * linux/arch/arm/kernel/traps.c 3 * 4 * Copyright (C) 1995-2009 Russell King 5 * Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * 'traps.c' handles hardware exceptions after we have saved some state in 12 * 'linux/arch/arm/lib/traps.S'. Mostly a debugging aid, but will probably 13 * kill the offending process. 14 */ 15 #include <linux/signal.h> 16 #include <linux/personality.h> 17 #include <linux/kallsyms.h> 18 #include <linux/spinlock.h> 19 #include <linux/uaccess.h> 20 #include <linux/hardirq.h> 21 #include <linux/kdebug.h> 22 #include <linux/module.h> 23 #include <linux/kexec.h> 24 #include <linux/bug.h> 25 #include <linux/delay.h> 26 #include <linux/init.h> 27 #include <linux/sched.h> 28 29 #include <linux/atomic.h> 30 #include <asm/cacheflush.h> 31 #include <asm/exception.h> 32 #include <asm/unistd.h> 33 #include <asm/traps.h> 34 #include <asm/unwind.h> 35 #include <asm/tls.h> 36 #include <asm/system_misc.h> 37 38 #include "signal.h" 39 40 static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" }; 41 42 void *vectors_page; 43 44 #ifdef CONFIG_DEBUG_USER 45 unsigned int user_debug; 46 47 static int __init user_debug_setup(char *str) 48 { 49 get_option(&str, &user_debug); 50 return 1; 51 } 52 __setup("user_debug=", user_debug_setup); 53 #endif 54 55 static void dump_mem(const char *, const char *, unsigned long, unsigned long); 56 57 void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame) 58 { 59 #ifdef CONFIG_KALLSYMS 60 printk("[<%08lx>] (%pS) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from); 61 #else 62 printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from); 63 #endif 64 65 if (in_exception_text(where)) 66 dump_mem("", "Exception stack", frame + 4, frame + 4 + sizeof(struct pt_regs)); 67 } 68 69 #ifndef CONFIG_ARM_UNWIND 70 /* 71 * Stack pointers should always be within the kernels view of 72 * physical memory. If it is not there, then we can't dump 73 * out any information relating to the stack. 74 */ 75 static int verify_stack(unsigned long sp) 76 { 77 if (sp < PAGE_OFFSET || 78 (sp > (unsigned long)high_memory && high_memory != NULL)) 79 return -EFAULT; 80 81 return 0; 82 } 83 #endif 84 85 /* 86 * Dump out the contents of some memory nicely... 87 */ 88 static void dump_mem(const char *lvl, const char *str, unsigned long bottom, 89 unsigned long top) 90 { 91 unsigned long first; 92 mm_segment_t fs; 93 int i; 94 95 /* 96 * We need to switch to kernel mode so that we can use __get_user 97 * to safely read from kernel space. Note that we now dump the 98 * code first, just in case the backtrace kills us. 99 */ 100 fs = get_fs(); 101 set_fs(KERNEL_DS); 102 103 printk("%s%s(0x%08lx to 0x%08lx)\n", lvl, str, bottom, top); 104 105 for (first = bottom & ~31; first < top; first += 32) { 106 unsigned long p; 107 char str[sizeof(" 12345678") * 8 + 1]; 108 109 memset(str, ' ', sizeof(str)); 110 str[sizeof(str) - 1] = '\0'; 111 112 for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { 113 if (p >= bottom && p < top) { 114 unsigned long val; 115 if (__get_user(val, (unsigned long *)p) == 0) 116 sprintf(str + i * 9, " %08lx", val); 117 else 118 sprintf(str + i * 9, " ????????"); 119 } 120 } 121 printk("%s%04lx:%s\n", lvl, first & 0xffff, str); 122 } 123 124 set_fs(fs); 125 } 126 127 static void dump_instr(const char *lvl, struct pt_regs *regs) 128 { 129 unsigned long addr = instruction_pointer(regs); 130 const int thumb = thumb_mode(regs); 131 const int width = thumb ? 4 : 8; 132 mm_segment_t fs; 133 char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str; 134 int i; 135 136 /* 137 * We need to switch to kernel mode so that we can use __get_user 138 * to safely read from kernel space. Note that we now dump the 139 * code first, just in case the backtrace kills us. 140 */ 141 fs = get_fs(); 142 set_fs(KERNEL_DS); 143 144 for (i = -4; i < 1 + !!thumb; i++) { 145 unsigned int val, bad; 146 147 if (thumb) 148 bad = __get_user(val, &((u16 *)addr)[i]); 149 else 150 bad = __get_user(val, &((u32 *)addr)[i]); 151 152 if (!bad) 153 p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ", 154 width, val); 155 else { 156 p += sprintf(p, "bad PC value"); 157 break; 158 } 159 } 160 printk("%sCode: %s\n", lvl, str); 161 162 set_fs(fs); 163 } 164 165 #ifdef CONFIG_ARM_UNWIND 166 static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) 167 { 168 unwind_backtrace(regs, tsk); 169 } 170 #else 171 static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) 172 { 173 unsigned int fp, mode; 174 int ok = 1; 175 176 printk("Backtrace: "); 177 178 if (!tsk) 179 tsk = current; 180 181 if (regs) { 182 fp = regs->ARM_fp; 183 mode = processor_mode(regs); 184 } else if (tsk != current) { 185 fp = thread_saved_fp(tsk); 186 mode = 0x10; 187 } else { 188 asm("mov %0, fp" : "=r" (fp) : : "cc"); 189 mode = 0x10; 190 } 191 192 if (!fp) { 193 printk("no frame pointer"); 194 ok = 0; 195 } else if (verify_stack(fp)) { 196 printk("invalid frame pointer 0x%08x", fp); 197 ok = 0; 198 } else if (fp < (unsigned long)end_of_stack(tsk)) 199 printk("frame pointer underflow"); 200 printk("\n"); 201 202 if (ok) 203 c_backtrace(fp, mode); 204 } 205 #endif 206 207 void dump_stack(void) 208 { 209 dump_backtrace(NULL, NULL); 210 } 211 212 EXPORT_SYMBOL(dump_stack); 213 214 void show_stack(struct task_struct *tsk, unsigned long *sp) 215 { 216 dump_backtrace(NULL, tsk); 217 barrier(); 218 } 219 220 #ifdef CONFIG_PREEMPT 221 #define S_PREEMPT " PREEMPT" 222 #else 223 #define S_PREEMPT "" 224 #endif 225 #ifdef CONFIG_SMP 226 #define S_SMP " SMP" 227 #else 228 #define S_SMP "" 229 #endif 230 #ifdef CONFIG_THUMB2_KERNEL 231 #define S_ISA " THUMB2" 232 #else 233 #define S_ISA " ARM" 234 #endif 235 236 static int __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs) 237 { 238 struct task_struct *tsk = thread->task; 239 static int die_counter; 240 int ret; 241 242 printk(KERN_EMERG "Internal error: %s: %x [#%d]" S_PREEMPT S_SMP 243 S_ISA "\n", str, err, ++die_counter); 244 245 /* trap and error numbers are mostly meaningless on ARM */ 246 ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, SIGSEGV); 247 if (ret == NOTIFY_STOP) 248 return ret; 249 250 print_modules(); 251 __show_regs(regs); 252 printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n", 253 TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1); 254 255 if (!user_mode(regs) || in_interrupt()) { 256 dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp, 257 THREAD_SIZE + (unsigned long)task_stack_page(tsk)); 258 dump_backtrace(regs, tsk); 259 dump_instr(KERN_EMERG, regs); 260 } 261 262 return ret; 263 } 264 265 static DEFINE_RAW_SPINLOCK(die_lock); 266 267 /* 268 * This function is protected against re-entrancy. 269 */ 270 void die(const char *str, struct pt_regs *regs, int err) 271 { 272 struct thread_info *thread = current_thread_info(); 273 int ret; 274 enum bug_trap_type bug_type = BUG_TRAP_TYPE_NONE; 275 276 oops_enter(); 277 278 raw_spin_lock_irq(&die_lock); 279 console_verbose(); 280 bust_spinlocks(1); 281 if (!user_mode(regs)) 282 bug_type = report_bug(regs->ARM_pc, regs); 283 if (bug_type != BUG_TRAP_TYPE_NONE) 284 str = "Oops - BUG"; 285 ret = __die(str, err, thread, regs); 286 287 if (regs && kexec_should_crash(thread->task)) 288 crash_kexec(regs); 289 290 bust_spinlocks(0); 291 add_taint(TAINT_DIE); 292 raw_spin_unlock_irq(&die_lock); 293 oops_exit(); 294 295 if (in_interrupt()) 296 panic("Fatal exception in interrupt"); 297 if (panic_on_oops) 298 panic("Fatal exception"); 299 if (ret != NOTIFY_STOP) 300 do_exit(SIGSEGV); 301 } 302 303 void arm_notify_die(const char *str, struct pt_regs *regs, 304 struct siginfo *info, unsigned long err, unsigned long trap) 305 { 306 if (user_mode(regs)) { 307 current->thread.error_code = err; 308 current->thread.trap_no = trap; 309 310 force_sig_info(info->si_signo, info, current); 311 } else { 312 die(str, regs, err); 313 } 314 } 315 316 #ifdef CONFIG_GENERIC_BUG 317 318 int is_valid_bugaddr(unsigned long pc) 319 { 320 #ifdef CONFIG_THUMB2_KERNEL 321 unsigned short bkpt; 322 #else 323 unsigned long bkpt; 324 #endif 325 326 if (probe_kernel_address((unsigned *)pc, bkpt)) 327 return 0; 328 329 return bkpt == BUG_INSTR_VALUE; 330 } 331 332 #endif 333 334 static LIST_HEAD(undef_hook); 335 static DEFINE_RAW_SPINLOCK(undef_lock); 336 337 void register_undef_hook(struct undef_hook *hook) 338 { 339 unsigned long flags; 340 341 raw_spin_lock_irqsave(&undef_lock, flags); 342 list_add(&hook->node, &undef_hook); 343 raw_spin_unlock_irqrestore(&undef_lock, flags); 344 } 345 346 void unregister_undef_hook(struct undef_hook *hook) 347 { 348 unsigned long flags; 349 350 raw_spin_lock_irqsave(&undef_lock, flags); 351 list_del(&hook->node); 352 raw_spin_unlock_irqrestore(&undef_lock, flags); 353 } 354 355 static int call_undef_hook(struct pt_regs *regs, unsigned int instr) 356 { 357 struct undef_hook *hook; 358 unsigned long flags; 359 int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL; 360 361 raw_spin_lock_irqsave(&undef_lock, flags); 362 list_for_each_entry(hook, &undef_hook, node) 363 if ((instr & hook->instr_mask) == hook->instr_val && 364 (regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val) 365 fn = hook->fn; 366 raw_spin_unlock_irqrestore(&undef_lock, flags); 367 368 return fn ? fn(regs, instr) : 1; 369 } 370 371 asmlinkage void __exception do_undefinstr(struct pt_regs *regs) 372 { 373 unsigned int correction = thumb_mode(regs) ? 2 : 4; 374 unsigned int instr; 375 siginfo_t info; 376 void __user *pc; 377 378 /* 379 * According to the ARM ARM, PC is 2 or 4 bytes ahead, 380 * depending whether we're in Thumb mode or not. 381 * Correct this offset. 382 */ 383 regs->ARM_pc -= correction; 384 385 pc = (void __user *)instruction_pointer(regs); 386 387 if (processor_mode(regs) == SVC_MODE) { 388 #ifdef CONFIG_THUMB2_KERNEL 389 if (thumb_mode(regs)) { 390 instr = ((u16 *)pc)[0]; 391 if (is_wide_instruction(instr)) { 392 instr <<= 16; 393 instr |= ((u16 *)pc)[1]; 394 } 395 } else 396 #endif 397 instr = *(u32 *) pc; 398 } else if (thumb_mode(regs)) { 399 get_user(instr, (u16 __user *)pc); 400 if (is_wide_instruction(instr)) { 401 unsigned int instr2; 402 get_user(instr2, (u16 __user *)pc+1); 403 instr <<= 16; 404 instr |= instr2; 405 } 406 } else { 407 get_user(instr, (u32 __user *)pc); 408 } 409 410 if (call_undef_hook(regs, instr) == 0) 411 return; 412 413 #ifdef CONFIG_DEBUG_USER 414 if (user_debug & UDBG_UNDEFINED) { 415 printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n", 416 current->comm, task_pid_nr(current), pc); 417 dump_instr(KERN_INFO, regs); 418 } 419 #endif 420 421 info.si_signo = SIGILL; 422 info.si_errno = 0; 423 info.si_code = ILL_ILLOPC; 424 info.si_addr = pc; 425 426 arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6); 427 } 428 429 asmlinkage void do_unexp_fiq (struct pt_regs *regs) 430 { 431 printk("Hmm. Unexpected FIQ received, but trying to continue\n"); 432 printk("You may have a hardware problem...\n"); 433 } 434 435 /* 436 * bad_mode handles the impossible case in the vectors. If you see one of 437 * these, then it's extremely serious, and could mean you have buggy hardware. 438 * It never returns, and never tries to sync. We hope that we can at least 439 * dump out some state information... 440 */ 441 asmlinkage void bad_mode(struct pt_regs *regs, int reason) 442 { 443 console_verbose(); 444 445 printk(KERN_CRIT "Bad mode in %s handler detected\n", handler[reason]); 446 447 die("Oops - bad mode", regs, 0); 448 local_irq_disable(); 449 panic("bad mode"); 450 } 451 452 static int bad_syscall(int n, struct pt_regs *regs) 453 { 454 struct thread_info *thread = current_thread_info(); 455 siginfo_t info; 456 457 if ((current->personality & PER_MASK) != PER_LINUX && 458 thread->exec_domain->handler) { 459 thread->exec_domain->handler(n, regs); 460 return regs->ARM_r0; 461 } 462 463 #ifdef CONFIG_DEBUG_USER 464 if (user_debug & UDBG_SYSCALL) { 465 printk(KERN_ERR "[%d] %s: obsolete system call %08x.\n", 466 task_pid_nr(current), current->comm, n); 467 dump_instr(KERN_ERR, regs); 468 } 469 #endif 470 471 info.si_signo = SIGILL; 472 info.si_errno = 0; 473 info.si_code = ILL_ILLTRP; 474 info.si_addr = (void __user *)instruction_pointer(regs) - 475 (thumb_mode(regs) ? 2 : 4); 476 477 arm_notify_die("Oops - bad syscall", regs, &info, n, 0); 478 479 return regs->ARM_r0; 480 } 481 482 static inline int 483 do_cache_op(unsigned long start, unsigned long end, int flags) 484 { 485 struct mm_struct *mm = current->active_mm; 486 struct vm_area_struct *vma; 487 488 if (end < start || flags) 489 return -EINVAL; 490 491 down_read(&mm->mmap_sem); 492 vma = find_vma(mm, start); 493 if (vma && vma->vm_start < end) { 494 if (start < vma->vm_start) 495 start = vma->vm_start; 496 if (end > vma->vm_end) 497 end = vma->vm_end; 498 499 up_read(&mm->mmap_sem); 500 return flush_cache_user_range(start, end); 501 } 502 up_read(&mm->mmap_sem); 503 return -EINVAL; 504 } 505 506 /* 507 * Handle all unrecognised system calls. 508 * 0x9f0000 - 0x9fffff are some more esoteric system calls 509 */ 510 #define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE) 511 asmlinkage int arm_syscall(int no, struct pt_regs *regs) 512 { 513 struct thread_info *thread = current_thread_info(); 514 siginfo_t info; 515 516 if ((no >> 16) != (__ARM_NR_BASE>> 16)) 517 return bad_syscall(no, regs); 518 519 switch (no & 0xffff) { 520 case 0: /* branch through 0 */ 521 info.si_signo = SIGSEGV; 522 info.si_errno = 0; 523 info.si_code = SEGV_MAPERR; 524 info.si_addr = NULL; 525 526 arm_notify_die("branch through zero", regs, &info, 0, 0); 527 return 0; 528 529 case NR(breakpoint): /* SWI BREAK_POINT */ 530 regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; 531 ptrace_break(current, regs); 532 return regs->ARM_r0; 533 534 /* 535 * Flush a region from virtual address 'r0' to virtual address 'r1' 536 * _exclusive_. There is no alignment requirement on either address; 537 * user space does not need to know the hardware cache layout. 538 * 539 * r2 contains flags. It should ALWAYS be passed as ZERO until it 540 * is defined to be something else. For now we ignore it, but may 541 * the fires of hell burn in your belly if you break this rule. ;) 542 * 543 * (at a later date, we may want to allow this call to not flush 544 * various aspects of the cache. Passing '0' will guarantee that 545 * everything necessary gets flushed to maintain consistency in 546 * the specified region). 547 */ 548 case NR(cacheflush): 549 return do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2); 550 551 case NR(usr26): 552 if (!(elf_hwcap & HWCAP_26BIT)) 553 break; 554 regs->ARM_cpsr &= ~MODE32_BIT; 555 return regs->ARM_r0; 556 557 case NR(usr32): 558 if (!(elf_hwcap & HWCAP_26BIT)) 559 break; 560 regs->ARM_cpsr |= MODE32_BIT; 561 return regs->ARM_r0; 562 563 case NR(set_tls): 564 thread->tp_value = regs->ARM_r0; 565 if (tls_emu) 566 return 0; 567 if (has_tls_reg) { 568 asm ("mcr p15, 0, %0, c13, c0, 3" 569 : : "r" (regs->ARM_r0)); 570 } else { 571 /* 572 * User space must never try to access this directly. 573 * Expect your app to break eventually if you do so. 574 * The user helper at 0xffff0fe0 must be used instead. 575 * (see entry-armv.S for details) 576 */ 577 *((unsigned int *)0xffff0ff0) = regs->ARM_r0; 578 } 579 return 0; 580 581 #ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG 582 /* 583 * Atomically store r1 in *r2 if *r2 is equal to r0 for user space. 584 * Return zero in r0 if *MEM was changed or non-zero if no exchange 585 * happened. Also set the user C flag accordingly. 586 * If access permissions have to be fixed up then non-zero is 587 * returned and the operation has to be re-attempted. 588 * 589 * *NOTE*: This is a ghost syscall private to the kernel. Only the 590 * __kuser_cmpxchg code in entry-armv.S should be aware of its 591 * existence. Don't ever use this from user code. 592 */ 593 case NR(cmpxchg): 594 for (;;) { 595 extern void do_DataAbort(unsigned long addr, unsigned int fsr, 596 struct pt_regs *regs); 597 unsigned long val; 598 unsigned long addr = regs->ARM_r2; 599 struct mm_struct *mm = current->mm; 600 pgd_t *pgd; pmd_t *pmd; pte_t *pte; 601 spinlock_t *ptl; 602 603 regs->ARM_cpsr &= ~PSR_C_BIT; 604 down_read(&mm->mmap_sem); 605 pgd = pgd_offset(mm, addr); 606 if (!pgd_present(*pgd)) 607 goto bad_access; 608 pmd = pmd_offset(pgd, addr); 609 if (!pmd_present(*pmd)) 610 goto bad_access; 611 pte = pte_offset_map_lock(mm, pmd, addr, &ptl); 612 if (!pte_present(*pte) || !pte_write(*pte) || !pte_dirty(*pte)) { 613 pte_unmap_unlock(pte, ptl); 614 goto bad_access; 615 } 616 val = *(unsigned long *)addr; 617 val -= regs->ARM_r0; 618 if (val == 0) { 619 *(unsigned long *)addr = regs->ARM_r1; 620 regs->ARM_cpsr |= PSR_C_BIT; 621 } 622 pte_unmap_unlock(pte, ptl); 623 up_read(&mm->mmap_sem); 624 return val; 625 626 bad_access: 627 up_read(&mm->mmap_sem); 628 /* simulate a write access fault */ 629 do_DataAbort(addr, 15 + (1 << 11), regs); 630 } 631 #endif 632 633 default: 634 /* Calls 9f00xx..9f07ff are defined to return -ENOSYS 635 if not implemented, rather than raising SIGILL. This 636 way the calling program can gracefully determine whether 637 a feature is supported. */ 638 if ((no & 0xffff) <= 0x7ff) 639 return -ENOSYS; 640 break; 641 } 642 #ifdef CONFIG_DEBUG_USER 643 /* 644 * experience shows that these seem to indicate that 645 * something catastrophic has happened 646 */ 647 if (user_debug & UDBG_SYSCALL) { 648 printk("[%d] %s: arm syscall %d\n", 649 task_pid_nr(current), current->comm, no); 650 dump_instr("", regs); 651 if (user_mode(regs)) { 652 __show_regs(regs); 653 c_backtrace(regs->ARM_fp, processor_mode(regs)); 654 } 655 } 656 #endif 657 info.si_signo = SIGILL; 658 info.si_errno = 0; 659 info.si_code = ILL_ILLTRP; 660 info.si_addr = (void __user *)instruction_pointer(regs) - 661 (thumb_mode(regs) ? 2 : 4); 662 663 arm_notify_die("Oops - bad syscall(2)", regs, &info, no, 0); 664 return 0; 665 } 666 667 #ifdef CONFIG_TLS_REG_EMUL 668 669 /* 670 * We might be running on an ARMv6+ processor which should have the TLS 671 * register but for some reason we can't use it, or maybe an SMP system 672 * using a pre-ARMv6 processor (there are apparently a few prototypes like 673 * that in existence) and therefore access to that register must be 674 * emulated. 675 */ 676 677 static int get_tp_trap(struct pt_regs *regs, unsigned int instr) 678 { 679 int reg = (instr >> 12) & 15; 680 if (reg == 15) 681 return 1; 682 regs->uregs[reg] = current_thread_info()->tp_value; 683 regs->ARM_pc += 4; 684 return 0; 685 } 686 687 static struct undef_hook arm_mrc_hook = { 688 .instr_mask = 0x0fff0fff, 689 .instr_val = 0x0e1d0f70, 690 .cpsr_mask = PSR_T_BIT, 691 .cpsr_val = 0, 692 .fn = get_tp_trap, 693 }; 694 695 static int __init arm_mrc_hook_init(void) 696 { 697 register_undef_hook(&arm_mrc_hook); 698 return 0; 699 } 700 701 late_initcall(arm_mrc_hook_init); 702 703 #endif 704 705 void __bad_xchg(volatile void *ptr, int size) 706 { 707 printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n", 708 __builtin_return_address(0), ptr, size); 709 BUG(); 710 } 711 EXPORT_SYMBOL(__bad_xchg); 712 713 /* 714 * A data abort trap was taken, but we did not handle the instruction. 715 * Try to abort the user program, or panic if it was the kernel. 716 */ 717 asmlinkage void 718 baddataabort(int code, unsigned long instr, struct pt_regs *regs) 719 { 720 unsigned long addr = instruction_pointer(regs); 721 siginfo_t info; 722 723 #ifdef CONFIG_DEBUG_USER 724 if (user_debug & UDBG_BADABORT) { 725 printk(KERN_ERR "[%d] %s: bad data abort: code %d instr 0x%08lx\n", 726 task_pid_nr(current), current->comm, code, instr); 727 dump_instr(KERN_ERR, regs); 728 show_pte(current->mm, addr); 729 } 730 #endif 731 732 info.si_signo = SIGILL; 733 info.si_errno = 0; 734 info.si_code = ILL_ILLOPC; 735 info.si_addr = (void __user *)addr; 736 737 arm_notify_die("unknown data abort code", regs, &info, instr, 0); 738 } 739 740 void __readwrite_bug(const char *fn) 741 { 742 printk("%s called, but not implemented\n", fn); 743 BUG(); 744 } 745 EXPORT_SYMBOL(__readwrite_bug); 746 747 void __pte_error(const char *file, int line, pte_t pte) 748 { 749 printk("%s:%d: bad pte %08llx.\n", file, line, (long long)pte_val(pte)); 750 } 751 752 void __pmd_error(const char *file, int line, pmd_t pmd) 753 { 754 printk("%s:%d: bad pmd %08llx.\n", file, line, (long long)pmd_val(pmd)); 755 } 756 757 void __pgd_error(const char *file, int line, pgd_t pgd) 758 { 759 printk("%s:%d: bad pgd %08llx.\n", file, line, (long long)pgd_val(pgd)); 760 } 761 762 asmlinkage void __div0(void) 763 { 764 printk("Division by zero in kernel.\n"); 765 dump_stack(); 766 } 767 EXPORT_SYMBOL(__div0); 768 769 void abort(void) 770 { 771 BUG(); 772 773 /* if that doesn't kill us, halt */ 774 panic("Oops failed to kill thread"); 775 } 776 EXPORT_SYMBOL(abort); 777 778 void __init trap_init(void) 779 { 780 return; 781 } 782 783 static void __init kuser_get_tls_init(unsigned long vectors) 784 { 785 /* 786 * vectors + 0xfe0 = __kuser_get_tls 787 * vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8 788 */ 789 if (tls_emu || has_tls_reg) 790 memcpy((void *)vectors + 0xfe0, (void *)vectors + 0xfe8, 4); 791 } 792 793 void __init early_trap_init(void *vectors_base) 794 { 795 unsigned long vectors = (unsigned long)vectors_base; 796 extern char __stubs_start[], __stubs_end[]; 797 extern char __vectors_start[], __vectors_end[]; 798 extern char __kuser_helper_start[], __kuser_helper_end[]; 799 int kuser_sz = __kuser_helper_end - __kuser_helper_start; 800 801 vectors_page = vectors_base; 802 803 /* 804 * Copy the vectors, stubs and kuser helpers (in entry-armv.S) 805 * into the vector page, mapped at 0xffff0000, and ensure these 806 * are visible to the instruction stream. 807 */ 808 memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start); 809 memcpy((void *)vectors + 0x200, __stubs_start, __stubs_end - __stubs_start); 810 memcpy((void *)vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); 811 812 /* 813 * Do processor specific fixups for the kuser helpers 814 */ 815 kuser_get_tls_init(vectors); 816 817 /* 818 * Copy signal return handlers into the vector page, and 819 * set sigreturn to be a pointer to these. 820 */ 821 memcpy((void *)(vectors + KERN_SIGRETURN_CODE - CONFIG_VECTORS_BASE), 822 sigreturn_codes, sizeof(sigreturn_codes)); 823 memcpy((void *)(vectors + KERN_RESTART_CODE - CONFIG_VECTORS_BASE), 824 syscall_restart_code, sizeof(syscall_restart_code)); 825 826 flush_icache_range(vectors, vectors + PAGE_SIZE); 827 modify_domain(DOMAIN_USER, DOMAIN_CLIENT); 828 } 829