mirror of https://gitee.com/openkylin/linux.git
811 lines
20 KiB
C
811 lines
20 KiB
C
/*
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* linux/arch/arm/kernel/traps.c
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*
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* Copyright (C) 1995-2009 Russell King
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* Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* 'traps.c' handles hardware exceptions after we have saved some state in
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* 'linux/arch/arm/lib/traps.S'. Mostly a debugging aid, but will probably
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* kill the offending process.
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*/
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#include <linux/signal.h>
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#include <linux/personality.h>
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#include <linux/kallsyms.h>
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#include <linux/spinlock.h>
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#include <linux/uaccess.h>
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#include <linux/hardirq.h>
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#include <linux/kdebug.h>
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#include <linux/module.h>
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#include <linux/kexec.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/atomic.h>
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#include <asm/cacheflush.h>
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#include <asm/exception.h>
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#include <asm/system.h>
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#include <asm/unistd.h>
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#include <asm/traps.h>
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#include <asm/unwind.h>
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#include <asm/tls.h>
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#include "signal.h"
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static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" };
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void *vectors_page;
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#ifdef CONFIG_DEBUG_USER
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unsigned int user_debug;
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static int __init user_debug_setup(char *str)
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{
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get_option(&str, &user_debug);
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return 1;
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}
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__setup("user_debug=", user_debug_setup);
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#endif
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static void dump_mem(const char *, const char *, unsigned long, unsigned long);
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void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame)
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{
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#ifdef CONFIG_KALLSYMS
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printk("[<%08lx>] (%pS) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from);
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#else
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printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from);
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#endif
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if (in_exception_text(where))
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dump_mem("", "Exception stack", frame + 4, frame + 4 + sizeof(struct pt_regs));
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}
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#ifndef CONFIG_ARM_UNWIND
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/*
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* Stack pointers should always be within the kernels view of
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* physical memory. If it is not there, then we can't dump
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* out any information relating to the stack.
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*/
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static int verify_stack(unsigned long sp)
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{
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if (sp < PAGE_OFFSET ||
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(sp > (unsigned long)high_memory && high_memory != NULL))
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return -EFAULT;
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return 0;
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}
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#endif
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/*
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* Dump out the contents of some memory nicely...
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*/
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static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
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unsigned long top)
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{
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unsigned long first;
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mm_segment_t fs;
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int i;
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/*
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* We need to switch to kernel mode so that we can use __get_user
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* to safely read from kernel space. Note that we now dump the
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* code first, just in case the backtrace kills us.
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*/
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fs = get_fs();
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set_fs(KERNEL_DS);
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printk("%s%s(0x%08lx to 0x%08lx)\n", lvl, str, bottom, top);
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for (first = bottom & ~31; first < top; first += 32) {
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unsigned long p;
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char str[sizeof(" 12345678") * 8 + 1];
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memset(str, ' ', sizeof(str));
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str[sizeof(str) - 1] = '\0';
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for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
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if (p >= bottom && p < top) {
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unsigned long val;
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if (__get_user(val, (unsigned long *)p) == 0)
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sprintf(str + i * 9, " %08lx", val);
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else
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sprintf(str + i * 9, " ????????");
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}
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}
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printk("%s%04lx:%s\n", lvl, first & 0xffff, str);
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}
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set_fs(fs);
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}
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static void dump_instr(const char *lvl, struct pt_regs *regs)
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{
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unsigned long addr = instruction_pointer(regs);
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const int thumb = thumb_mode(regs);
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const int width = thumb ? 4 : 8;
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mm_segment_t fs;
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char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
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int i;
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/*
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* We need to switch to kernel mode so that we can use __get_user
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* to safely read from kernel space. Note that we now dump the
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* code first, just in case the backtrace kills us.
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*/
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fs = get_fs();
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set_fs(KERNEL_DS);
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for (i = -4; i < 1 + !!thumb; i++) {
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unsigned int val, bad;
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if (thumb)
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bad = __get_user(val, &((u16 *)addr)[i]);
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else
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bad = __get_user(val, &((u32 *)addr)[i]);
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if (!bad)
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p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ",
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width, val);
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else {
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p += sprintf(p, "bad PC value");
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break;
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}
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}
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printk("%sCode: %s\n", lvl, str);
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set_fs(fs);
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}
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#ifdef CONFIG_ARM_UNWIND
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static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
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{
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unwind_backtrace(regs, tsk);
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}
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#else
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static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
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{
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unsigned int fp, mode;
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int ok = 1;
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printk("Backtrace: ");
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if (!tsk)
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tsk = current;
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if (regs) {
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fp = regs->ARM_fp;
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mode = processor_mode(regs);
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} else if (tsk != current) {
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fp = thread_saved_fp(tsk);
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mode = 0x10;
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} else {
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asm("mov %0, fp" : "=r" (fp) : : "cc");
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mode = 0x10;
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}
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if (!fp) {
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printk("no frame pointer");
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ok = 0;
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} else if (verify_stack(fp)) {
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printk("invalid frame pointer 0x%08x", fp);
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ok = 0;
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} else if (fp < (unsigned long)end_of_stack(tsk))
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printk("frame pointer underflow");
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printk("\n");
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if (ok)
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c_backtrace(fp, mode);
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}
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#endif
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void dump_stack(void)
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{
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dump_backtrace(NULL, NULL);
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}
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EXPORT_SYMBOL(dump_stack);
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void show_stack(struct task_struct *tsk, unsigned long *sp)
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{
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dump_backtrace(NULL, tsk);
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barrier();
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}
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#ifdef CONFIG_PREEMPT
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#define S_PREEMPT " PREEMPT"
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#else
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#define S_PREEMPT ""
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#endif
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#ifdef CONFIG_SMP
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#define S_SMP " SMP"
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#else
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#define S_SMP ""
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#endif
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static int __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs)
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{
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struct task_struct *tsk = thread->task;
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static int die_counter;
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int ret;
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printk(KERN_EMERG "Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
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str, err, ++die_counter);
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/* trap and error numbers are mostly meaningless on ARM */
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ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, SIGSEGV);
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if (ret == NOTIFY_STOP)
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return ret;
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print_modules();
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__show_regs(regs);
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printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n",
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TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
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if (!user_mode(regs) || in_interrupt()) {
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dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp,
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THREAD_SIZE + (unsigned long)task_stack_page(tsk));
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dump_backtrace(regs, tsk);
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dump_instr(KERN_EMERG, regs);
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}
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return ret;
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}
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static DEFINE_SPINLOCK(die_lock);
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/*
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* This function is protected against re-entrancy.
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*/
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void die(const char *str, struct pt_regs *regs, int err)
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{
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struct thread_info *thread = current_thread_info();
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int ret;
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oops_enter();
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spin_lock_irq(&die_lock);
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console_verbose();
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bust_spinlocks(1);
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ret = __die(str, err, thread, regs);
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if (regs && kexec_should_crash(thread->task))
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crash_kexec(regs);
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bust_spinlocks(0);
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add_taint(TAINT_DIE);
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spin_unlock_irq(&die_lock);
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oops_exit();
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if (in_interrupt())
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panic("Fatal exception in interrupt");
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if (panic_on_oops)
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panic("Fatal exception");
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if (ret != NOTIFY_STOP)
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do_exit(SIGSEGV);
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}
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void arm_notify_die(const char *str, struct pt_regs *regs,
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struct siginfo *info, unsigned long err, unsigned long trap)
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{
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if (user_mode(regs)) {
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current->thread.error_code = err;
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current->thread.trap_no = trap;
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force_sig_info(info->si_signo, info, current);
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} else {
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die(str, regs, err);
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}
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}
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static LIST_HEAD(undef_hook);
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static DEFINE_SPINLOCK(undef_lock);
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void register_undef_hook(struct undef_hook *hook)
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{
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unsigned long flags;
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spin_lock_irqsave(&undef_lock, flags);
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list_add(&hook->node, &undef_hook);
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spin_unlock_irqrestore(&undef_lock, flags);
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}
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void unregister_undef_hook(struct undef_hook *hook)
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{
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unsigned long flags;
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spin_lock_irqsave(&undef_lock, flags);
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list_del(&hook->node);
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spin_unlock_irqrestore(&undef_lock, flags);
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}
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static int call_undef_hook(struct pt_regs *regs, unsigned int instr)
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{
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struct undef_hook *hook;
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unsigned long flags;
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int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL;
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spin_lock_irqsave(&undef_lock, flags);
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list_for_each_entry(hook, &undef_hook, node)
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if ((instr & hook->instr_mask) == hook->instr_val &&
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(regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val)
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fn = hook->fn;
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spin_unlock_irqrestore(&undef_lock, flags);
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return fn ? fn(regs, instr) : 1;
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}
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asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
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{
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unsigned int correction = thumb_mode(regs) ? 2 : 4;
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unsigned int instr;
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siginfo_t info;
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void __user *pc;
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/*
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* According to the ARM ARM, PC is 2 or 4 bytes ahead,
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* depending whether we're in Thumb mode or not.
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* Correct this offset.
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*/
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regs->ARM_pc -= correction;
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pc = (void __user *)instruction_pointer(regs);
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if (processor_mode(regs) == SVC_MODE) {
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#ifdef CONFIG_THUMB2_KERNEL
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if (thumb_mode(regs)) {
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instr = ((u16 *)pc)[0];
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if (is_wide_instruction(instr)) {
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instr <<= 16;
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instr |= ((u16 *)pc)[1];
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}
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} else
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#endif
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instr = *(u32 *) pc;
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} else if (thumb_mode(regs)) {
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get_user(instr, (u16 __user *)pc);
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if (is_wide_instruction(instr)) {
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unsigned int instr2;
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get_user(instr2, (u16 __user *)pc+1);
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instr <<= 16;
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instr |= instr2;
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}
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} else {
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get_user(instr, (u32 __user *)pc);
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}
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if (call_undef_hook(regs, instr) == 0)
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return;
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#ifdef CONFIG_DEBUG_USER
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if (user_debug & UDBG_UNDEFINED) {
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printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n",
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current->comm, task_pid_nr(current), pc);
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dump_instr(KERN_INFO, regs);
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}
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#endif
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info.si_signo = SIGILL;
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info.si_errno = 0;
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info.si_code = ILL_ILLOPC;
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info.si_addr = pc;
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arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6);
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}
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asmlinkage void do_unexp_fiq (struct pt_regs *regs)
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{
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printk("Hmm. Unexpected FIQ received, but trying to continue\n");
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printk("You may have a hardware problem...\n");
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}
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/*
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* bad_mode handles the impossible case in the vectors. If you see one of
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* these, then it's extremely serious, and could mean you have buggy hardware.
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* It never returns, and never tries to sync. We hope that we can at least
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* dump out some state information...
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*/
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asmlinkage void bad_mode(struct pt_regs *regs, int reason)
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{
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console_verbose();
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printk(KERN_CRIT "Bad mode in %s handler detected\n", handler[reason]);
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die("Oops - bad mode", regs, 0);
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local_irq_disable();
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panic("bad mode");
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}
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static int bad_syscall(int n, struct pt_regs *regs)
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{
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struct thread_info *thread = current_thread_info();
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siginfo_t info;
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if ((current->personality & PER_MASK) != PER_LINUX &&
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thread->exec_domain->handler) {
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thread->exec_domain->handler(n, regs);
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return regs->ARM_r0;
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}
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#ifdef CONFIG_DEBUG_USER
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if (user_debug & UDBG_SYSCALL) {
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printk(KERN_ERR "[%d] %s: obsolete system call %08x.\n",
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task_pid_nr(current), current->comm, n);
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dump_instr(KERN_ERR, regs);
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}
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#endif
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info.si_signo = SIGILL;
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info.si_errno = 0;
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info.si_code = ILL_ILLTRP;
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info.si_addr = (void __user *)instruction_pointer(regs) -
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(thumb_mode(regs) ? 2 : 4);
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arm_notify_die("Oops - bad syscall", regs, &info, n, 0);
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return regs->ARM_r0;
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}
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static inline void
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do_cache_op(unsigned long start, unsigned long end, int flags)
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{
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struct mm_struct *mm = current->active_mm;
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struct vm_area_struct *vma;
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if (end < start || flags)
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return;
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down_read(&mm->mmap_sem);
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vma = find_vma(mm, start);
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if (vma && vma->vm_start < end) {
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if (start < vma->vm_start)
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start = vma->vm_start;
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if (end > vma->vm_end)
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end = vma->vm_end;
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flush_cache_user_range(vma, start, end);
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}
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up_read(&mm->mmap_sem);
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}
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/*
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* Handle all unrecognised system calls.
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* 0x9f0000 - 0x9fffff are some more esoteric system calls
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*/
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#define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE)
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asmlinkage int arm_syscall(int no, struct pt_regs *regs)
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{
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struct thread_info *thread = current_thread_info();
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siginfo_t info;
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if ((no >> 16) != (__ARM_NR_BASE>> 16))
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return bad_syscall(no, regs);
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switch (no & 0xffff) {
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case 0: /* branch through 0 */
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info.si_signo = SIGSEGV;
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info.si_errno = 0;
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info.si_code = SEGV_MAPERR;
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info.si_addr = NULL;
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arm_notify_die("branch through zero", regs, &info, 0, 0);
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return 0;
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case NR(breakpoint): /* SWI BREAK_POINT */
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regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
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ptrace_break(current, regs);
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return regs->ARM_r0;
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/*
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* Flush a region from virtual address 'r0' to virtual address 'r1'
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* _exclusive_. There is no alignment requirement on either address;
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* user space does not need to know the hardware cache layout.
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*
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* r2 contains flags. It should ALWAYS be passed as ZERO until it
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* is defined to be something else. For now we ignore it, but may
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* the fires of hell burn in your belly if you break this rule. ;)
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*
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* (at a later date, we may want to allow this call to not flush
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* various aspects of the cache. Passing '0' will guarantee that
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* everything necessary gets flushed to maintain consistency in
|
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* the specified region).
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*/
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case NR(cacheflush):
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do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2);
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return 0;
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case NR(usr26):
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if (!(elf_hwcap & HWCAP_26BIT))
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break;
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regs->ARM_cpsr &= ~MODE32_BIT;
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return regs->ARM_r0;
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case NR(usr32):
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if (!(elf_hwcap & HWCAP_26BIT))
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break;
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regs->ARM_cpsr |= MODE32_BIT;
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return regs->ARM_r0;
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|
|
case NR(set_tls):
|
|
thread->tp_value = regs->ARM_r0;
|
|
if (tls_emu)
|
|
return 0;
|
|
if (has_tls_reg) {
|
|
asm ("mcr p15, 0, %0, c13, c0, 3"
|
|
: : "r" (regs->ARM_r0));
|
|
} else {
|
|
/*
|
|
* User space must never try to access this directly.
|
|
* Expect your app to break eventually if you do so.
|
|
* The user helper at 0xffff0fe0 must be used instead.
|
|
* (see entry-armv.S for details)
|
|
*/
|
|
*((unsigned int *)0xffff0ff0) = regs->ARM_r0;
|
|
}
|
|
return 0;
|
|
|
|
#ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG
|
|
/*
|
|
* Atomically store r1 in *r2 if *r2 is equal to r0 for user space.
|
|
* Return zero in r0 if *MEM was changed or non-zero if no exchange
|
|
* happened. Also set the user C flag accordingly.
|
|
* If access permissions have to be fixed up then non-zero is
|
|
* returned and the operation has to be re-attempted.
|
|
*
|
|
* *NOTE*: This is a ghost syscall private to the kernel. Only the
|
|
* __kuser_cmpxchg code in entry-armv.S should be aware of its
|
|
* existence. Don't ever use this from user code.
|
|
*/
|
|
case NR(cmpxchg):
|
|
for (;;) {
|
|
extern void do_DataAbort(unsigned long addr, unsigned int fsr,
|
|
struct pt_regs *regs);
|
|
unsigned long val;
|
|
unsigned long addr = regs->ARM_r2;
|
|
struct mm_struct *mm = current->mm;
|
|
pgd_t *pgd; pmd_t *pmd; pte_t *pte;
|
|
spinlock_t *ptl;
|
|
|
|
regs->ARM_cpsr &= ~PSR_C_BIT;
|
|
down_read(&mm->mmap_sem);
|
|
pgd = pgd_offset(mm, addr);
|
|
if (!pgd_present(*pgd))
|
|
goto bad_access;
|
|
pmd = pmd_offset(pgd, addr);
|
|
if (!pmd_present(*pmd))
|
|
goto bad_access;
|
|
pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
|
|
if (!pte_present(*pte) || !pte_write(*pte) || !pte_dirty(*pte)) {
|
|
pte_unmap_unlock(pte, ptl);
|
|
goto bad_access;
|
|
}
|
|
val = *(unsigned long *)addr;
|
|
val -= regs->ARM_r0;
|
|
if (val == 0) {
|
|
*(unsigned long *)addr = regs->ARM_r1;
|
|
regs->ARM_cpsr |= PSR_C_BIT;
|
|
}
|
|
pte_unmap_unlock(pte, ptl);
|
|
up_read(&mm->mmap_sem);
|
|
return val;
|
|
|
|
bad_access:
|
|
up_read(&mm->mmap_sem);
|
|
/* simulate a write access fault */
|
|
do_DataAbort(addr, 15 + (1 << 11), regs);
|
|
}
|
|
#endif
|
|
|
|
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 & 0xffff) <= 0x7ff)
|
|
return -ENOSYS;
|
|
break;
|
|
}
|
|
#ifdef CONFIG_DEBUG_USER
|
|
/*
|
|
* experience shows that these seem to indicate that
|
|
* something catastrophic has happened
|
|
*/
|
|
if (user_debug & UDBG_SYSCALL) {
|
|
printk("[%d] %s: arm syscall %d\n",
|
|
task_pid_nr(current), 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 __user *)instruction_pointer(regs) -
|
|
(thumb_mode(regs) ? 2 : 4);
|
|
|
|
arm_notify_die("Oops - bad syscall(2)", regs, &info, no, 0);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_TLS_REG_EMUL
|
|
|
|
/*
|
|
* We might be running on an ARMv6+ processor which should have the TLS
|
|
* register but for some reason we can't use it, or maybe an SMP system
|
|
* using a pre-ARMv6 processor (there are apparently a few prototypes like
|
|
* that in existence) and therefore access to that register must be
|
|
* emulated.
|
|
*/
|
|
|
|
static int get_tp_trap(struct pt_regs *regs, unsigned int instr)
|
|
{
|
|
int reg = (instr >> 12) & 15;
|
|
if (reg == 15)
|
|
return 1;
|
|
regs->uregs[reg] = current_thread_info()->tp_value;
|
|
regs->ARM_pc += 4;
|
|
return 0;
|
|
}
|
|
|
|
static struct undef_hook arm_mrc_hook = {
|
|
.instr_mask = 0x0fff0fff,
|
|
.instr_val = 0x0e1d0f70,
|
|
.cpsr_mask = PSR_T_BIT,
|
|
.cpsr_val = 0,
|
|
.fn = get_tp_trap,
|
|
};
|
|
|
|
static int __init arm_mrc_hook_init(void)
|
|
{
|
|
register_undef_hook(&arm_mrc_hook);
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(arm_mrc_hook_init);
|
|
|
|
#endif
|
|
|
|
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();
|
|
}
|
|
EXPORT_SYMBOL(__bad_xchg);
|
|
|
|
/*
|
|
* 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
|
|
if (user_debug & UDBG_BADABORT) {
|
|
printk(KERN_ERR "[%d] %s: bad data abort: code %d instr 0x%08lx\n",
|
|
task_pid_nr(current), current->comm, code, instr);
|
|
dump_instr(KERN_ERR, regs);
|
|
show_pte(current->mm, addr);
|
|
}
|
|
#endif
|
|
|
|
info.si_signo = SIGILL;
|
|
info.si_errno = 0;
|
|
info.si_code = ILL_ILLOPC;
|
|
info.si_addr = (void __user *)addr;
|
|
|
|
arm_notify_die("unknown data abort code", regs, &info, instr, 0);
|
|
}
|
|
|
|
void __attribute__((noreturn)) __bug(const char *file, int line)
|
|
{
|
|
printk(KERN_CRIT"kernel BUG at %s:%d!\n", file, line);
|
|
*(int *)0 = 0;
|
|
|
|
/* Avoid "noreturn function does return" */
|
|
for (;;);
|
|
}
|
|
EXPORT_SYMBOL(__bug);
|
|
|
|
void __readwrite_bug(const char *fn)
|
|
{
|
|
printk("%s called, but not implemented\n", fn);
|
|
BUG();
|
|
}
|
|
EXPORT_SYMBOL(__readwrite_bug);
|
|
|
|
void __pte_error(const char *file, int line, pte_t pte)
|
|
{
|
|
printk("%s:%d: bad pte %08llx.\n", file, line, (long long)pte_val(pte));
|
|
}
|
|
|
|
void __pmd_error(const char *file, int line, pmd_t pmd)
|
|
{
|
|
printk("%s:%d: bad pmd %08llx.\n", file, line, (long long)pmd_val(pmd));
|
|
}
|
|
|
|
void __pgd_error(const char *file, int line, pgd_t pgd)
|
|
{
|
|
printk("%s:%d: bad pgd %08llx.\n", file, line, (long long)pgd_val(pgd));
|
|
}
|
|
|
|
asmlinkage void __div0(void)
|
|
{
|
|
printk("Division by zero in kernel.\n");
|
|
dump_stack();
|
|
}
|
|
EXPORT_SYMBOL(__div0);
|
|
|
|
void abort(void)
|
|
{
|
|
BUG();
|
|
|
|
/* if that doesn't kill us, halt */
|
|
panic("Oops failed to kill thread");
|
|
}
|
|
EXPORT_SYMBOL(abort);
|
|
|
|
void __init trap_init(void)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static void __init kuser_get_tls_init(unsigned long vectors)
|
|
{
|
|
/*
|
|
* vectors + 0xfe0 = __kuser_get_tls
|
|
* vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8
|
|
*/
|
|
if (tls_emu || has_tls_reg)
|
|
memcpy((void *)vectors + 0xfe0, (void *)vectors + 0xfe8, 4);
|
|
}
|
|
|
|
void __init early_trap_init(void)
|
|
{
|
|
#if defined(CONFIG_CPU_USE_DOMAINS)
|
|
unsigned long vectors = CONFIG_VECTORS_BASE;
|
|
#else
|
|
unsigned long vectors = (unsigned long)vectors_page;
|
|
#endif
|
|
extern char __stubs_start[], __stubs_end[];
|
|
extern char __vectors_start[], __vectors_end[];
|
|
extern char __kuser_helper_start[], __kuser_helper_end[];
|
|
int kuser_sz = __kuser_helper_end - __kuser_helper_start;
|
|
|
|
/*
|
|
* Copy the vectors, stubs and kuser helpers (in entry-armv.S)
|
|
* into the vector page, mapped at 0xffff0000, and ensure these
|
|
* are visible to the instruction stream.
|
|
*/
|
|
memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start);
|
|
memcpy((void *)vectors + 0x200, __stubs_start, __stubs_end - __stubs_start);
|
|
memcpy((void *)vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz);
|
|
|
|
/*
|
|
* Do processor specific fixups for the kuser helpers
|
|
*/
|
|
kuser_get_tls_init(vectors);
|
|
|
|
/*
|
|
* Copy signal return handlers into the vector page, and
|
|
* set sigreturn to be a pointer to these.
|
|
*/
|
|
memcpy((void *)(vectors + KERN_SIGRETURN_CODE - CONFIG_VECTORS_BASE),
|
|
sigreturn_codes, sizeof(sigreturn_codes));
|
|
memcpy((void *)(vectors + KERN_RESTART_CODE - CONFIG_VECTORS_BASE),
|
|
syscall_restart_code, sizeof(syscall_restart_code));
|
|
|
|
flush_icache_range(vectors, vectors + PAGE_SIZE);
|
|
modify_domain(DOMAIN_USER, DOMAIN_CLIENT);
|
|
}
|