2 * linux/arch/arm/kernel/traps.c
4 * Copyright (C) 1995-2009 Russell King
5 * Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds
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.
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.
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>
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>
36 #include <asm/system_misc.h>
37 #include <linux/aee.h>
38 static const char *handler
[]= {
43 "undefined instruction",
48 #ifdef CONFIG_DEBUG_USER
49 unsigned int user_debug
;
51 static int __init
user_debug_setup(char *str
)
53 get_option(&str
, &user_debug
);
56 __setup("user_debug=", user_debug_setup
);
59 static void dump_mem(const char *, const char *, unsigned long, unsigned long);
61 void dump_backtrace_entry(unsigned long where
, unsigned long from
, unsigned long frame
)
63 #ifdef CONFIG_KALLSYMS
64 printk("[<%08lx>] (%pS) from [<%08lx>] (%pS)\n", where
, (void *)where
, from
, (void *)from
);
66 printk("Function entered at [<%08lx>] from [<%08lx>]\n", where
, from
);
69 if (in_exception_text(where
))
70 dump_mem("", "Exception stack", frame
+ 4, frame
+ 4 + sizeof(struct pt_regs
));
73 #ifndef CONFIG_ARM_UNWIND
75 * Stack pointers should always be within the kernels view of
76 * physical memory. If it is not there, then we can't dump
77 * out any information relating to the stack.
79 static int verify_stack(unsigned long sp
)
81 if (sp
< PAGE_OFFSET
||
82 (sp
> (unsigned long)high_memory
&& high_memory
!= NULL
))
90 * Dump out the contents of some memory nicely...
92 static void dump_mem(const char *lvl
, const char *str
, unsigned long bottom
,
100 * We need to switch to kernel mode so that we can use __get_user
101 * to safely read from kernel space. Note that we now dump the
102 * code first, just in case the backtrace kills us.
107 printk("%s%s(0x%08lx to 0x%08lx)\n", lvl
, str
, bottom
, top
);
109 for (first
= bottom
& ~31; first
< top
; first
+= 32) {
111 char str
[sizeof(" 12345678") * 8 + 1];
113 memset(str
, ' ', sizeof(str
));
114 str
[sizeof(str
) - 1] = '\0';
116 for (p
= first
, i
= 0; i
< 8 && p
< top
; i
++, p
+= 4) {
117 if (p
>= bottom
&& p
< top
) {
119 if (__get_user(val
, (unsigned long *)p
) == 0)
120 sprintf(str
+ i
* 9, " %08lx", val
);
122 sprintf(str
+ i
* 9, " ????????");
125 printk("%s%04lx:%s\n", lvl
, first
& 0xffff, str
);
131 static void dump_instr(const char *lvl
, struct pt_regs
*regs
)
133 unsigned long addr
= instruction_pointer(regs
);
134 const int thumb
= thumb_mode(regs
);
135 const int width
= thumb
? 4 : 8;
137 char str
[sizeof("00000000 ") * 5 + 2 + 1], *p
= str
;
141 * We need to switch to kernel mode so that we can use __get_user
142 * to safely read from kernel space. Note that we now dump the
143 * code first, just in case the backtrace kills us.
148 for (i
= -4; i
< 1 + !!thumb
; i
++) {
149 unsigned int val
, bad
;
152 bad
= __get_user(val
, &((u16
*)addr
)[i
]);
154 bad
= __get_user(val
, &((u32
*)addr
)[i
]);
157 p
+= sprintf(p
, i
== 0 ? "(%0*x) " : "%0*x ",
160 p
+= sprintf(p
, "bad PC value");
164 printk("%sCode: %s\n", lvl
, str
);
169 #ifdef CONFIG_ARM_UNWIND
170 static inline void dump_backtrace(struct pt_regs
*regs
, struct task_struct
*tsk
)
172 unwind_backtrace(regs
, tsk
);
175 static void dump_backtrace(struct pt_regs
*regs
, struct task_struct
*tsk
)
177 unsigned int fp
, mode
;
180 printk("Backtrace: ");
187 mode
= processor_mode(regs
);
188 } else if (tsk
!= current
) {
189 fp
= thread_saved_fp(tsk
);
192 asm("mov %0, fp" : "=r" (fp
) : : "cc");
197 printk("no frame pointer");
199 } else if (verify_stack(fp
)) {
200 printk("invalid frame pointer 0x%08x", fp
);
202 } else if (fp
< (unsigned long)end_of_stack(tsk
))
203 printk("frame pointer underflow");
207 c_backtrace(fp
, mode
);
211 void dump_stack(void)
213 dump_backtrace(NULL
, NULL
);
216 EXPORT_SYMBOL(dump_stack
);
218 void show_stack(struct task_struct
*tsk
, unsigned long *sp
)
220 dump_backtrace(NULL
, tsk
);
224 #ifdef CONFIG_PREEMPT
225 #define S_PREEMPT " PREEMPT"
234 #ifdef CONFIG_THUMB2_KERNEL
235 #define S_ISA " THUMB2"
240 static int __die(const char *str
, int err
, struct pt_regs
*regs
)
242 struct task_struct
*tsk
= current
;
243 unsigned long sp
, stack
;
244 static int die_counter
;
247 printk(KERN_EMERG
"Internal error: %s: %x [#%d]" S_PREEMPT S_SMP
248 S_ISA
"\n", str
, err
, ++die_counter
);
250 /* trap and error numbers are mostly meaningless on ARM */
251 ret
= notify_die(DIE_OOPS
, str
, regs
, err
, tsk
->thread
.trap_no
, SIGSEGV
);
252 if (ret
== NOTIFY_STOP
)
257 printk(KERN_EMERG
"Process %.*s (pid: %d, stack limit = 0x%p)\n",
258 TASK_COMM_LEN
, tsk
->comm
, task_pid_nr(tsk
), end_of_stack(tsk
));
260 if (!user_mode(regs
) || in_interrupt()) {
262 stack
= (unsigned long)task_stack_page(tsk
);
263 dump_mem(KERN_EMERG
, "Stack: ", sp
, ALIGN(sp
, THREAD_SIZE
));
264 if (sp
< stack
|| (sp
- stack
) > THREAD_SIZE
) {
265 printk(KERN_EMERG
"Invalid sp[%lx] or stack address[%lx]\n", sp
, stack
);
266 dump_mem(KERN_EMERG
, "Stack(backup) ", stack
, THREAD_SIZE
+ stack
);
268 dump_backtrace(regs
, tsk
);
269 dump_instr(KERN_EMERG
, regs
);
275 static arch_spinlock_t die_lock
= __ARCH_SPIN_LOCK_UNLOCKED
;
276 static int die_owner
= -1;
277 static unsigned int die_nest_count
;
279 static unsigned long oops_begin(void)
286 /* racy, but better than risking deadlock. */
287 raw_local_irq_save(flags
);
288 cpu
= smp_processor_id();
289 if (!arch_spin_trylock(&die_lock
)) {
290 if (cpu
== die_owner
)
291 /* nested oops. should stop eventually */;
293 arch_spin_lock(&die_lock
);
302 static void oops_end(unsigned long flags
, struct pt_regs
*regs
, int signr
)
304 if (regs
&& kexec_should_crash(current
))
309 add_taint(TAINT_DIE
, LOCKDEP_NOW_UNRELIABLE
);
312 /* Nest count reaches zero, release the lock. */
313 arch_spin_unlock(&die_lock
);
314 /* not enable irq incase softirq many turn off msdc clock */
315 //raw_local_irq_restore(flags);
319 panic("Fatal exception in interrupt");
321 panic("Fatal exception");
327 * This function is protected against re-entrancy.
329 void die(const char *str
, struct pt_regs
*regs
, int err
)
331 enum bug_trap_type bug_type
= BUG_TRAP_TYPE_NONE
;
332 unsigned long flags
= oops_begin();
335 if (!user_mode(regs
))
336 bug_type
= report_bug(regs
->ARM_pc
, regs
);
337 if (bug_type
!= BUG_TRAP_TYPE_NONE
)
340 if (__die(str
, err
, regs
))
343 oops_end(flags
, regs
, sig
);
346 void arm_notify_die(const char *str
, struct pt_regs
*regs
,
347 struct siginfo
*info
, unsigned long err
, unsigned long trap
)
349 if (user_mode(regs
)) {
350 current
->thread
.error_code
= err
;
351 current
->thread
.trap_no
= trap
;
353 force_sig_info(info
->si_signo
, info
, current
);
359 #ifdef CONFIG_GENERIC_BUG
361 int is_valid_bugaddr(unsigned long pc
)
363 #ifdef CONFIG_THUMB2_KERNEL
369 if (probe_kernel_address((unsigned *)pc
, bkpt
))
372 return bkpt
== BUG_INSTR_VALUE
;
377 static LIST_HEAD(undef_hook
);
378 static DEFINE_RAW_SPINLOCK(undef_lock
);
380 void register_undef_hook(struct undef_hook
*hook
)
384 raw_spin_lock_irqsave(&undef_lock
, flags
);
385 list_add(&hook
->node
, &undef_hook
);
386 raw_spin_unlock_irqrestore(&undef_lock
, flags
);
389 void unregister_undef_hook(struct undef_hook
*hook
)
393 raw_spin_lock_irqsave(&undef_lock
, flags
);
394 list_del(&hook
->node
);
395 raw_spin_unlock_irqrestore(&undef_lock
, flags
);
398 static int call_undef_hook(struct pt_regs
*regs
, unsigned int instr
)
400 struct undef_hook
*hook
;
402 int (*fn
)(struct pt_regs
*regs
, unsigned int instr
) = NULL
;
404 raw_spin_lock_irqsave(&undef_lock
, flags
);
405 list_for_each_entry(hook
, &undef_hook
, node
)
406 if ((instr
& hook
->instr_mask
) == hook
->instr_val
&&
407 (regs
->ARM_cpsr
& hook
->cpsr_mask
) == hook
->cpsr_val
)
409 raw_spin_unlock_irqrestore(&undef_lock
, flags
);
411 return fn
? fn(regs
, instr
) : 1;
414 volatile static void __user
*prev_undefinstr_pc
=0;
415 volatile static int prev_undefinstr_counter
=0;
416 volatile static unsigned long prev_undefinstr_curr
=0;
418 asmlinkage
void __exception
do_undefinstr(struct pt_regs
*regs
)
420 struct thread_info
*thread
= current_thread_info();
426 if (!user_mode(regs
)) {
428 if (thread
->cpu_excp
== 1) {
429 thread
->regs_on_excp
= (void *)regs
;
430 aee_excp_regs
= (void*)regs
;
432 if (thread
->cpu_excp
>= 2) {
433 aee_stop_nested_panic(regs
);
437 pc
= (void __user
*)instruction_pointer(regs
);
439 if (processor_mode(regs
) == SVC_MODE
) {
440 #ifdef CONFIG_THUMB2_KERNEL
441 if (thumb_mode(regs
)) {
442 instr
= ((u16
*)pc
)[0];
443 if (is_wide_instruction(instr
)) {
445 instr
|= ((u16
*)pc
)[1];
450 } else if (thumb_mode(regs
)) {
451 if (get_user(instr
, (u16 __user
*)pc
))
453 if (is_wide_instruction(instr
)) {
455 if (get_user(instr2
, (u16 __user
*)pc
+1))
460 } else if (get_user(instr
, (u32 __user
*)pc
)) {
464 ret
= call_undef_hook(regs
, instr
);
466 if (!user_mode(regs
)) {
473 #ifdef CONFIG_DEBUG_USER
474 if (user_debug
& UDBG_UNDEFINED
) {
475 printk(KERN_INFO
"%s (%d): undefined instruction: pc=%p\n",
476 current
->comm
, task_pid_nr(current
), pc
);
477 dump_instr(KERN_INFO
, regs
);
481 /* Place the SIGILL ICache Invalidate after the Debugger Undefined-Instruction Solution. */
482 if ((processor_mode(regs
) == USR_MODE
) || (processor_mode(regs
) == SVC_MODE
)) {
483 /* Only do it for User-Space Application. */
484 printk("USR_MODE/SVC_MODE Undefined Instruction Address curr:%p pc=%p:%p\n",
485 (void *)current
, (void *)pc
, (void *)prev_undefinstr_pc
);
486 if ((prev_undefinstr_pc
!= pc
) || (prev_undefinstr_curr
!= (unsigned long)current
)) {
487 /* If the current process or program counter is changed......renew the counter. */
488 printk("First Time Recovery curr:%p pc=%p:%p\n",
489 (void *)current
, (void *)pc
, (void *)prev_undefinstr_pc
);
490 prev_undefinstr_pc
= pc
;
491 prev_undefinstr_curr
= (unsigned long)current
;
492 prev_undefinstr_counter
= 0;
493 __cpuc_flush_icache_all();
495 if (!user_mode(regs
)) {
500 else if(prev_undefinstr_counter
< 1) {
501 printk("2nd Time Recovery curr:%p pc=%p:%p\n",
502 (void *)current
, (void *)pc
, (void *)prev_undefinstr_pc
);
503 prev_undefinstr_counter
++;
504 __cpuc_flush_icache_all();
506 if (!user_mode(regs
)) {
511 prev_undefinstr_counter
++;
512 if(prev_undefinstr_counter
>= 4) {
513 /* 2=first time SigILL,3=2nd time NE-SigILL,4=3rd time CoreDump-SigILL */
514 prev_undefinstr_pc
= 0;
515 prev_undefinstr_curr
= 0;
516 prev_undefinstr_counter
= 0;
518 printk("Go to ARM Notify Die curr:%p pc=%p:%p\n",
519 (void *)current
, (void *)pc
, (void *)prev_undefinstr_pc
);
522 info
.si_signo
= SIGILL
;
524 info
.si_code
= ILL_ILLOPC
;
527 arm_notify_die("Oops - undefined instruction", regs
, &info
, 0, 6);
530 asmlinkage
void do_unexp_fiq (struct pt_regs
*regs
)
532 printk("Hmm. Unexpected FIQ received, but trying to continue\n");
533 printk("You may have a hardware problem...\n");
537 * bad_mode handles the impossible case in the vectors. If you see one of
538 * these, then it's extremely serious, and could mean you have buggy hardware.
539 * It never returns, and never tries to sync. We hope that we can at least
540 * dump out some state information...
542 asmlinkage
void bad_mode(struct pt_regs
*regs
, int reason
)
546 printk(KERN_CRIT
"Bad mode in %s handler detected\n", handler
[reason
]);
548 die("Oops - bad mode", regs
, 0);
553 static int bad_syscall(int n
, struct pt_regs
*regs
)
555 struct thread_info
*thread
= current_thread_info();
558 if ((current
->personality
& PER_MASK
) != PER_LINUX
&&
559 thread
->exec_domain
->handler
) {
560 thread
->exec_domain
->handler(n
, regs
);
564 #ifdef CONFIG_DEBUG_USER
565 if (user_debug
& UDBG_SYSCALL
) {
566 printk(KERN_ERR
"[%d] %s: obsolete system call %08x.\n",
567 task_pid_nr(current
), current
->comm
, n
);
568 dump_instr(KERN_ERR
, regs
);
572 info
.si_signo
= SIGILL
;
574 info
.si_code
= ILL_ILLTRP
;
575 info
.si_addr
= (void __user
*)instruction_pointer(regs
) -
576 (thumb_mode(regs
) ? 2 : 4);
578 arm_notify_die("Oops - bad syscall", regs
, &info
, n
, 0);
584 do_cache_op(unsigned long start
, unsigned long end
, int flags
)
586 struct mm_struct
*mm
= current
->active_mm
;
587 struct vm_area_struct
*vma
;
589 if (end
< start
|| flags
)
592 down_read(&mm
->mmap_sem
);
593 vma
= find_vma(mm
, start
);
594 if (vma
&& vma
->vm_start
< end
) {
595 if (start
< vma
->vm_start
)
596 start
= vma
->vm_start
;
597 if (end
> vma
->vm_end
)
600 up_read(&mm
->mmap_sem
);
601 return flush_cache_user_range(start
, end
);
603 up_read(&mm
->mmap_sem
);
608 * Handle all unrecognised system calls.
609 * 0x9f0000 - 0x9fffff are some more esoteric system calls
611 #define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE)
612 asmlinkage
int arm_syscall(int no
, struct pt_regs
*regs
)
614 struct thread_info
*thread
= current_thread_info();
617 if ((no
>> 16) != (__ARM_NR_BASE
>> 16))
618 return bad_syscall(no
, regs
);
620 switch (no
& 0xffff) {
621 case 0: /* branch through 0 */
622 info
.si_signo
= SIGSEGV
;
624 info
.si_code
= SEGV_MAPERR
;
627 arm_notify_die("branch through zero", regs
, &info
, 0, 0);
630 case NR(breakpoint
): /* SWI BREAK_POINT */
631 regs
->ARM_pc
-= thumb_mode(regs
) ? 2 : 4;
632 ptrace_break(current
, regs
);
636 * Flush a region from virtual address 'r0' to virtual address 'r1'
637 * _exclusive_. There is no alignment requirement on either address;
638 * user space does not need to know the hardware cache layout.
640 * r2 contains flags. It should ALWAYS be passed as ZERO until it
641 * is defined to be something else. For now we ignore it, but may
642 * the fires of hell burn in your belly if you break this rule. ;)
644 * (at a later date, we may want to allow this call to not flush
645 * various aspects of the cache. Passing '0' will guarantee that
646 * everything necessary gets flushed to maintain consistency in
647 * the specified region).
650 return do_cache_op(regs
->ARM_r0
, regs
->ARM_r1
, regs
->ARM_r2
);
653 if (!(elf_hwcap
& HWCAP_26BIT
))
655 regs
->ARM_cpsr
&= ~MODE32_BIT
;
659 if (!(elf_hwcap
& HWCAP_26BIT
))
661 regs
->ARM_cpsr
|= MODE32_BIT
;
665 thread
->tp_value
= regs
->ARM_r0
;
669 asm ("mcr p15, 0, %0, c13, c0, 3"
670 : : "r" (regs
->ARM_r0
));
673 * User space must never try to access this directly.
674 * Expect your app to break eventually if you do so.
675 * The user helper at 0xffff0fe0 must be used instead.
676 * (see entry-armv.S for details)
678 *((unsigned int *)0xffff0ff0) = regs
->ARM_r0
;
682 #ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG
684 * Atomically store r1 in *r2 if *r2 is equal to r0 for user space.
685 * Return zero in r0 if *MEM was changed or non-zero if no exchange
686 * happened. Also set the user C flag accordingly.
687 * If access permissions have to be fixed up then non-zero is
688 * returned and the operation has to be re-attempted.
690 * *NOTE*: This is a ghost syscall private to the kernel. Only the
691 * __kuser_cmpxchg code in entry-armv.S should be aware of its
692 * existence. Don't ever use this from user code.
696 extern void do_DataAbort(unsigned long addr
, unsigned int fsr
,
697 struct pt_regs
*regs
);
699 unsigned long addr
= regs
->ARM_r2
;
700 struct mm_struct
*mm
= current
->mm
;
701 pgd_t
*pgd
; pmd_t
*pmd
; pte_t
*pte
;
704 regs
->ARM_cpsr
&= ~PSR_C_BIT
;
705 down_read(&mm
->mmap_sem
);
706 pgd
= pgd_offset(mm
, addr
);
707 if (!pgd_present(*pgd
))
709 pmd
= pmd_offset(pgd
, addr
);
710 if (!pmd_present(*pmd
))
712 pte
= pte_offset_map_lock(mm
, pmd
, addr
, &ptl
);
713 if (!pte_present(*pte
) || !pte_write(*pte
) || !pte_dirty(*pte
)) {
714 pte_unmap_unlock(pte
, ptl
);
717 val
= *(unsigned long *)addr
;
720 *(unsigned long *)addr
= regs
->ARM_r1
;
721 regs
->ARM_cpsr
|= PSR_C_BIT
;
723 pte_unmap_unlock(pte
, ptl
);
724 up_read(&mm
->mmap_sem
);
728 up_read(&mm
->mmap_sem
);
729 /* simulate a write access fault */
730 do_DataAbort(addr
, 15 + (1 << 11), regs
);
735 /* Calls 9f00xx..9f07ff are defined to return -ENOSYS
736 if not implemented, rather than raising SIGILL. This
737 way the calling program can gracefully determine whether
738 a feature is supported. */
739 if ((no
& 0xffff) <= 0x7ff)
743 #ifdef CONFIG_DEBUG_USER
745 * experience shows that these seem to indicate that
746 * something catastrophic has happened
748 if (user_debug
& UDBG_SYSCALL
) {
749 printk("[%d] %s: arm syscall %d\n",
750 task_pid_nr(current
), current
->comm
, no
);
751 dump_instr("", regs
);
752 if (user_mode(regs
)) {
754 c_backtrace(regs
->ARM_fp
, processor_mode(regs
));
758 info
.si_signo
= SIGILL
;
760 info
.si_code
= ILL_ILLTRP
;
761 info
.si_addr
= (void __user
*)instruction_pointer(regs
) -
762 (thumb_mode(regs
) ? 2 : 4);
764 arm_notify_die("Oops - bad syscall(2)", regs
, &info
, no
, 0);
768 #ifdef CONFIG_TLS_REG_EMUL
771 * We might be running on an ARMv6+ processor which should have the TLS
772 * register but for some reason we can't use it, or maybe an SMP system
773 * using a pre-ARMv6 processor (there are apparently a few prototypes like
774 * that in existence) and therefore access to that register must be
778 static int get_tp_trap(struct pt_regs
*regs
, unsigned int instr
)
780 int reg
= (instr
>> 12) & 15;
783 regs
->uregs
[reg
] = current_thread_info()->tp_value
;
788 static struct undef_hook arm_mrc_hook
= {
789 .instr_mask
= 0x0fff0fff,
790 .instr_val
= 0x0e1d0f70,
791 .cpsr_mask
= PSR_T_BIT
,
796 static int __init
arm_mrc_hook_init(void)
798 register_undef_hook(&arm_mrc_hook
);
802 late_initcall(arm_mrc_hook_init
);
806 void __bad_xchg(volatile void *ptr
, int size
)
808 printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n",
809 __builtin_return_address(0), ptr
, size
);
812 EXPORT_SYMBOL(__bad_xchg
);
815 * A data abort trap was taken, but we did not handle the instruction.
816 * Try to abort the user program, or panic if it was the kernel.
819 baddataabort(int code
, unsigned long instr
, struct pt_regs
*regs
)
821 unsigned long addr
= instruction_pointer(regs
);
824 #ifdef CONFIG_DEBUG_USER
825 if (user_debug
& UDBG_BADABORT
) {
826 printk(KERN_ERR
"[%d] %s: bad data abort: code %d instr 0x%08lx\n",
827 task_pid_nr(current
), current
->comm
, code
, instr
);
828 dump_instr(KERN_ERR
, regs
);
829 show_pte(current
->mm
, addr
);
833 info
.si_signo
= SIGILL
;
835 info
.si_code
= ILL_ILLOPC
;
836 info
.si_addr
= (void __user
*)addr
;
838 arm_notify_die("unknown data abort code", regs
, &info
, instr
, 0);
841 void __readwrite_bug(const char *fn
)
843 printk("%s called, but not implemented\n", fn
);
846 EXPORT_SYMBOL(__readwrite_bug
);
848 void __pte_error(const char *file
, int line
, pte_t pte
)
850 printk("%s:%d: bad pte %08llx.\n", file
, line
, (long long)pte_val(pte
));
853 void __pmd_error(const char *file
, int line
, pmd_t pmd
)
855 printk("%s:%d: bad pmd %08llx.\n", file
, line
, (long long)pmd_val(pmd
));
858 void __pgd_error(const char *file
, int line
, pgd_t pgd
)
860 printk("%s:%d: bad pgd %08llx.\n", file
, line
, (long long)pgd_val(pgd
));
863 asmlinkage
void __div0(void)
865 printk("Division by zero in kernel.\n");
868 EXPORT_SYMBOL(__div0
);
874 /* if that doesn't kill us, halt */
875 panic("Oops failed to kill thread");
877 EXPORT_SYMBOL(abort
);
879 void __init
trap_init(void)
884 #ifdef CONFIG_KUSER_HELPERS
885 static void __init
kuser_init(void *vectors
)
887 extern char __kuser_helper_start
[], __kuser_helper_end
[];
888 int kuser_sz
= __kuser_helper_end
- __kuser_helper_start
;
890 memcpy(vectors
+ 0x1000 - kuser_sz
, __kuser_helper_start
, kuser_sz
);
893 * vectors + 0xfe0 = __kuser_get_tls
894 * vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8
896 if (tls_emu
|| has_tls_reg
)
897 memcpy(vectors
+ 0xfe0, vectors
+ 0xfe8, 4);
900 static void __init
kuser_init(void *vectors
)
905 void __init
early_trap_init(void *vectors_base
)
907 unsigned long vectors
= (unsigned long)vectors_base
;
908 extern char __stubs_start
[], __stubs_end
[];
909 extern char __vectors_start
[], __vectors_end
[];
912 vectors_page
= vectors_base
;
915 * Poison the vectors page with an undefined instruction. This
916 * instruction is chosen to be undefined for both ARM and Thumb
917 * ISAs. The Thumb version is an undefined instruction with a
918 * branch back to the undefined instruction.
920 for (i
= 0; i
< PAGE_SIZE
/ sizeof(u32
); i
++)
921 ((u32
*)vectors_base
)[i
] = 0xe7fddef1;
924 * Copy the vectors, stubs and kuser helpers (in entry-armv.S)
925 * into the vector page, mapped at 0xffff0000, and ensure these
926 * are visible to the instruction stream.
928 memcpy((void *)vectors
, __vectors_start
, __vectors_end
- __vectors_start
);
929 memcpy((void *)vectors
+ 0x1000, __stubs_start
, __stubs_end
- __stubs_start
);
931 kuser_init(vectors_base
);
933 flush_icache_range(vectors
, vectors
+ PAGE_SIZE
* 2);
934 modify_domain(DOMAIN_USER
, DOMAIN_CLIENT
);