1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
548 lines
12 KiB
C
548 lines
12 KiB
C
/*
|
|
* linux/arch/arm26/kernel/traps.c
|
|
*
|
|
* Copyright (C) 1995-2002 Russell King
|
|
* Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds
|
|
* Copyright (C) 2003 Ian Molton (ARM26)
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* 'traps.c' handles hardware exceptions after we have saved some state in
|
|
* 'linux/arch/arm26/lib/traps.S'. Mostly a debugging aid, but will probably
|
|
* kill the offending process.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/config.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/personality.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/elf.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/init.h>
|
|
|
|
#include <asm/atomic.h>
|
|
#include <asm/io.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/system.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/unistd.h>
|
|
#include <asm/semaphore.h>
|
|
|
|
#include "ptrace.h"
|
|
|
|
extern void c_backtrace (unsigned long fp, int pmode);
|
|
extern void show_pte(struct mm_struct *mm, unsigned long addr);
|
|
|
|
const char *processor_modes[] = { "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" };
|
|
|
|
static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" "*bad reason*"};
|
|
|
|
/*
|
|
* Stack pointers should always be within the kernels view of
|
|
* physical memory. If it is not there, then we can't dump
|
|
* out any information relating to the stack.
|
|
*/
|
|
static int verify_stack(unsigned long sp)
|
|
{
|
|
if (sp < PAGE_OFFSET || (sp > (unsigned long)high_memory && high_memory != 0))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Dump out the contents of some memory nicely...
|
|
*/
|
|
static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
|
|
{
|
|
unsigned long p = bottom & ~31;
|
|
mm_segment_t fs;
|
|
int i;
|
|
|
|
/*
|
|
* We need to switch to kernel mode so that we can use __get_user
|
|
* to safely read from kernel space. Note that we now dump the
|
|
* code first, just in case the backtrace kills us.
|
|
*/
|
|
fs = get_fs();
|
|
set_fs(KERNEL_DS);
|
|
|
|
printk("%s", str);
|
|
printk("(0x%08lx to 0x%08lx)\n", bottom, top);
|
|
|
|
for (p = bottom & ~31; p < top;) {
|
|
printk("%04lx: ", p & 0xffff);
|
|
|
|
for (i = 0; i < 8; i++, p += 4) {
|
|
unsigned int val;
|
|
|
|
if (p < bottom || p >= top)
|
|
printk(" ");
|
|
else {
|
|
__get_user(val, (unsigned long *)p);
|
|
printk("%08x ", val);
|
|
}
|
|
}
|
|
printk ("\n");
|
|
}
|
|
|
|
set_fs(fs);
|
|
}
|
|
|
|
static void dump_instr(struct pt_regs *regs)
|
|
{
|
|
unsigned long addr = instruction_pointer(regs);
|
|
const int width = 8;
|
|
mm_segment_t fs;
|
|
int i;
|
|
|
|
/*
|
|
* We need to switch to kernel mode so that we can use __get_user
|
|
* to safely read from kernel space. Note that we now dump the
|
|
* code first, just in case the backtrace kills us.
|
|
*/
|
|
fs = get_fs();
|
|
set_fs(KERNEL_DS);
|
|
|
|
printk("Code: ");
|
|
for (i = -4; i < 1; i++) {
|
|
unsigned int val, bad;
|
|
|
|
bad = __get_user(val, &((u32 *)addr)[i]);
|
|
|
|
if (!bad)
|
|
printk(i == 0 ? "(%0*x) " : "%0*x ", width, val);
|
|
else {
|
|
printk("bad PC value.");
|
|
break;
|
|
}
|
|
}
|
|
printk("\n");
|
|
|
|
set_fs(fs);
|
|
}
|
|
|
|
/*static*/ void __dump_stack(struct task_struct *tsk, unsigned long sp)
|
|
{
|
|
dump_mem("Stack: ", sp, 8192+(unsigned long)tsk->thread_info);
|
|
}
|
|
|
|
void dump_stack(void)
|
|
{
|
|
#ifdef CONFIG_DEBUG_ERRORS
|
|
__backtrace();
|
|
#endif
|
|
}
|
|
|
|
EXPORT_SYMBOL(dump_stack);
|
|
|
|
//FIXME - was a static fn
|
|
void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
|
|
{
|
|
unsigned int fp;
|
|
int ok = 1;
|
|
|
|
printk("Backtrace: ");
|
|
fp = regs->ARM_fp;
|
|
if (!fp) {
|
|
printk("no frame pointer");
|
|
ok = 0;
|
|
} else if (verify_stack(fp)) {
|
|
printk("invalid frame pointer 0x%08x", fp);
|
|
ok = 0;
|
|
} else if (fp < (unsigned long)(tsk->thread_info + 1))
|
|
printk("frame pointer underflow");
|
|
printk("\n");
|
|
|
|
if (ok)
|
|
c_backtrace(fp, processor_mode(regs));
|
|
}
|
|
|
|
/* FIXME - this is probably wrong.. */
|
|
void show_stack(struct task_struct *task, unsigned long *sp) {
|
|
dump_mem("Stack: ", (unsigned long)sp, 8192+(unsigned long)task->thread_info);
|
|
}
|
|
|
|
DEFINE_SPINLOCK(die_lock);
|
|
|
|
/*
|
|
* This function is protected against re-entrancy.
|
|
*/
|
|
NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
|
|
console_verbose();
|
|
spin_lock_irq(&die_lock);
|
|
|
|
printk("Internal error: %s: %x\n", str, err);
|
|
printk("CPU: %d\n", smp_processor_id());
|
|
show_regs(regs);
|
|
printk("Process %s (pid: %d, stack limit = 0x%p)\n",
|
|
current->comm, current->pid, tsk->thread_info + 1);
|
|
|
|
if (!user_mode(regs) || in_interrupt()) {
|
|
__dump_stack(tsk, (unsigned long)(regs + 1));
|
|
dump_backtrace(regs, tsk);
|
|
dump_instr(regs);
|
|
}
|
|
while(1);
|
|
spin_unlock_irq(&die_lock);
|
|
do_exit(SIGSEGV);
|
|
}
|
|
|
|
void die_if_kernel(const char *str, struct pt_regs *regs, int err)
|
|
{
|
|
if (user_mode(regs))
|
|
return;
|
|
|
|
die(str, regs, err);
|
|
}
|
|
|
|
static DECLARE_MUTEX(undef_sem);
|
|
static int (*undef_hook)(struct pt_regs *);
|
|
|
|
int request_undef_hook(int (*fn)(struct pt_regs *))
|
|
{
|
|
int ret = -EBUSY;
|
|
|
|
down(&undef_sem);
|
|
if (undef_hook == NULL) {
|
|
undef_hook = fn;
|
|
ret = 0;
|
|
}
|
|
up(&undef_sem);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int release_undef_hook(int (*fn)(struct pt_regs *))
|
|
{
|
|
int ret = -EINVAL;
|
|
|
|
down(&undef_sem);
|
|
if (undef_hook == fn) {
|
|
undef_hook = NULL;
|
|
ret = 0;
|
|
}
|
|
up(&undef_sem);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int undefined_extension(struct pt_regs *regs, unsigned int op)
|
|
{
|
|
switch (op) {
|
|
case 1: /* 0xde01 / 0x?7f001f0 */
|
|
ptrace_break(current, regs);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
asmlinkage void do_undefinstr(struct pt_regs *regs)
|
|
{
|
|
siginfo_t info;
|
|
void *pc;
|
|
|
|
regs->ARM_pc -= 4;
|
|
|
|
pc = (unsigned long *)instruction_pointer(regs); /* strip PSR */
|
|
|
|
if (user_mode(regs)) {
|
|
u32 instr;
|
|
|
|
get_user(instr, (u32 *)pc);
|
|
|
|
if ((instr & 0x0fff00ff) == 0x07f000f0 &&
|
|
undefined_extension(regs, (instr >> 8) & 255) == 0) {
|
|
regs->ARM_pc += 4;
|
|
return;
|
|
}
|
|
} else {
|
|
if (undef_hook && undef_hook(regs) == 0) {
|
|
regs->ARM_pc += 4;
|
|
return;
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_USER
|
|
printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n",
|
|
current->comm, current->pid, pc);
|
|
dump_instr(regs);
|
|
#endif
|
|
|
|
current->thread.error_code = 0;
|
|
current->thread.trap_no = 6;
|
|
|
|
info.si_signo = SIGILL;
|
|
info.si_errno = 0;
|
|
info.si_code = ILL_ILLOPC;
|
|
info.si_addr = pc;
|
|
|
|
force_sig_info(SIGILL, &info, current);
|
|
|
|
die_if_kernel("Oops - undefined instruction", regs, 0);
|
|
}
|
|
|
|
asmlinkage void do_excpt(unsigned long address, struct pt_regs *regs, int mode)
|
|
{
|
|
siginfo_t info;
|
|
|
|
#ifdef CONFIG_DEBUG_USER
|
|
printk(KERN_INFO "%s (%d): address exception: pc=%08lx\n",
|
|
current->comm, current->pid, instruction_pointer(regs));
|
|
dump_instr(regs);
|
|
#endif
|
|
|
|
current->thread.error_code = 0;
|
|
current->thread.trap_no = 11;
|
|
|
|
info.si_signo = SIGBUS;
|
|
info.si_errno = 0;
|
|
info.si_code = BUS_ADRERR;
|
|
info.si_addr = (void *)address;
|
|
|
|
force_sig_info(SIGBUS, &info, current);
|
|
|
|
die_if_kernel("Oops - address exception", regs, mode);
|
|
}
|
|
|
|
asmlinkage void do_unexp_fiq (struct pt_regs *regs)
|
|
{
|
|
#ifndef CONFIG_IGNORE_FIQ
|
|
printk("Hmm. Unexpected FIQ received, but trying to continue\n");
|
|
printk("You may have a hardware problem...\n");
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* bad_mode handles the impossible case in the vectors. If you see one of
|
|
* these, then it's extremely serious, and could mean you have buggy hardware.
|
|
* It never returns, and never tries to sync. We hope that we can at least
|
|
* dump out some state information...
|
|
*/
|
|
asmlinkage void bad_mode(struct pt_regs *regs, int reason, int proc_mode)
|
|
{
|
|
unsigned int vectors = vectors_base();
|
|
|
|
console_verbose();
|
|
|
|
printk(KERN_CRIT "Bad mode in %s handler detected: mode %s\n",
|
|
handler[reason<5?reason:4], processor_modes[proc_mode]);
|
|
|
|
/*
|
|
* Dump out the vectors and stub routines. Maybe a better solution
|
|
* would be to dump them out only if we detect that they are corrupted.
|
|
*/
|
|
dump_mem(KERN_CRIT "Vectors: ", vectors, vectors + 0x40);
|
|
dump_mem(KERN_CRIT "Stubs: ", vectors + 0x200, vectors + 0x4b8);
|
|
|
|
die("Oops", regs, 0);
|
|
local_irq_disable();
|
|
panic("bad mode");
|
|
}
|
|
|
|
static int bad_syscall(int n, struct pt_regs *regs)
|
|
{
|
|
struct thread_info *thread = current_thread_info();
|
|
siginfo_t info;
|
|
|
|
if (current->personality != PER_LINUX && thread->exec_domain->handler) {
|
|
thread->exec_domain->handler(n, regs);
|
|
return regs->ARM_r0;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_USER
|
|
printk(KERN_ERR "[%d] %s: obsolete system call %08x.\n",
|
|
current->pid, current->comm, n);
|
|
dump_instr(regs);
|
|
#endif
|
|
|
|
info.si_signo = SIGILL;
|
|
info.si_errno = 0;
|
|
info.si_code = ILL_ILLTRP;
|
|
info.si_addr = (void *)instruction_pointer(regs) - 4;
|
|
|
|
force_sig_info(SIGILL, &info, current);
|
|
die_if_kernel("Oops", regs, n);
|
|
return regs->ARM_r0;
|
|
}
|
|
|
|
static inline void
|
|
do_cache_op(unsigned long start, unsigned long end, int flags)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
|
|
if (end < start)
|
|
return;
|
|
|
|
vma = find_vma(current->active_mm, start);
|
|
if (vma && vma->vm_start < end) {
|
|
if (start < vma->vm_start)
|
|
start = vma->vm_start;
|
|
if (end > vma->vm_end)
|
|
end = vma->vm_end;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Handle all unrecognised system calls.
|
|
* 0x9f0000 - 0x9fffff are some more esoteric system calls
|
|
*/
|
|
#define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE)
|
|
asmlinkage int arm_syscall(int no, struct pt_regs *regs)
|
|
{
|
|
siginfo_t info;
|
|
|
|
if ((no >> 16) != 0x9f)
|
|
return bad_syscall(no, regs);
|
|
|
|
switch (no & 0xffff) {
|
|
case 0: /* branch through 0 */
|
|
info.si_signo = SIGSEGV;
|
|
info.si_errno = 0;
|
|
info.si_code = SEGV_MAPERR;
|
|
info.si_addr = NULL;
|
|
|
|
force_sig_info(SIGSEGV, &info, current);
|
|
|
|
die_if_kernel("branch through zero", regs, 0);
|
|
return 0;
|
|
|
|
case NR(breakpoint): /* SWI BREAK_POINT */
|
|
ptrace_break(current, regs);
|
|
return regs->ARM_r0;
|
|
|
|
case NR(cacheflush):
|
|
return 0;
|
|
|
|
case NR(usr26):
|
|
break;
|
|
|
|
default:
|
|
/* Calls 9f00xx..9f07ff are defined to return -ENOSYS
|
|
if not implemented, rather than raising SIGILL. This
|
|
way the calling program can gracefully determine whether
|
|
a feature is supported. */
|
|
if (no <= 0x7ff)
|
|
return -ENOSYS;
|
|
break;
|
|
}
|
|
#ifdef CONFIG_DEBUG_USER
|
|
/*
|
|
* experience shows that these seem to indicate that
|
|
* something catastrophic has happened
|
|
*/
|
|
printk("[%d] %s: arm syscall %d\n", current->pid, current->comm, no);
|
|
dump_instr(regs);
|
|
if (user_mode(regs)) {
|
|
show_regs(regs);
|
|
c_backtrace(regs->ARM_fp, processor_mode(regs));
|
|
}
|
|
#endif
|
|
info.si_signo = SIGILL;
|
|
info.si_errno = 0;
|
|
info.si_code = ILL_ILLTRP;
|
|
info.si_addr = (void *)instruction_pointer(regs) - 4;
|
|
|
|
force_sig_info(SIGILL, &info, current);
|
|
die_if_kernel("Oops", regs, no);
|
|
return 0;
|
|
}
|
|
|
|
void __bad_xchg(volatile void *ptr, int size)
|
|
{
|
|
printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n",
|
|
__builtin_return_address(0), ptr, size);
|
|
BUG();
|
|
}
|
|
|
|
/*
|
|
* A data abort trap was taken, but we did not handle the instruction.
|
|
* Try to abort the user program, or panic if it was the kernel.
|
|
*/
|
|
asmlinkage void
|
|
baddataabort(int code, unsigned long instr, struct pt_regs *regs)
|
|
{
|
|
unsigned long addr = instruction_pointer(regs);
|
|
siginfo_t info;
|
|
|
|
#ifdef CONFIG_DEBUG_USER
|
|
printk(KERN_ERR "[%d] %s: bad data abort: code %d instr 0x%08lx\n",
|
|
current->pid, current->comm, code, instr);
|
|
dump_instr(regs);
|
|
show_pte(current->mm, addr);
|
|
#endif
|
|
|
|
info.si_signo = SIGILL;
|
|
info.si_errno = 0;
|
|
info.si_code = ILL_ILLOPC;
|
|
info.si_addr = (void *)addr;
|
|
|
|
force_sig_info(SIGILL, &info, current);
|
|
die_if_kernel("unknown data abort code", regs, instr);
|
|
}
|
|
|
|
volatile void __bug(const char *file, int line, void *data)
|
|
{
|
|
printk(KERN_CRIT"kernel BUG at %s:%d!", file, line);
|
|
if (data)
|
|
printk(KERN_CRIT" - extra data = %p", data);
|
|
printk("\n");
|
|
*(int *)0 = 0;
|
|
}
|
|
|
|
void __readwrite_bug(const char *fn)
|
|
{
|
|
printk("%s called, but not implemented", fn);
|
|
BUG();
|
|
}
|
|
|
|
void __pte_error(const char *file, int line, unsigned long val)
|
|
{
|
|
printk("%s:%d: bad pte %08lx.\n", file, line, val);
|
|
}
|
|
|
|
void __pmd_error(const char *file, int line, unsigned long val)
|
|
{
|
|
printk("%s:%d: bad pmd %08lx.\n", file, line, val);
|
|
}
|
|
|
|
void __pgd_error(const char *file, int line, unsigned long val)
|
|
{
|
|
printk("%s:%d: bad pgd %08lx.\n", file, line, val);
|
|
}
|
|
|
|
asmlinkage void __div0(void)
|
|
{
|
|
printk("Division by zero in kernel.\n");
|
|
dump_stack();
|
|
}
|
|
|
|
void abort(void)
|
|
{
|
|
BUG();
|
|
|
|
/* if that doesn't kill us, halt */
|
|
panic("Oops failed to kill thread");
|
|
}
|
|
|
|
void __init trap_init(void)
|
|
{
|
|
extern void __trap_init(unsigned long);
|
|
unsigned long base = vectors_base();
|
|
|
|
__trap_init(base);
|
|
if (base != 0)
|
|
printk(KERN_DEBUG "Relocating machine vectors to 0x%08lx\n",
|
|
base);
|
|
}
|