Linux Kernel  3.7.1
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fault.c
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1 /*
2  * linux/arch/h8300/mm/fault.c
3  *
4  * Copyright (C) 1998 D. Jeff Dionne <[email protected]>,
5  * Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
6  *
7  * Based on:
8  *
9  * linux/arch/m68knommu/mm/fault.c
10  * linux/arch/m68k/mm/fault.c
11  *
12  * Copyright (C) 1995 Hamish Macdonald
13  */
14 
15 #include <linux/mman.h>
16 #include <linux/mm.h>
17 #include <linux/kernel.h>
18 #include <linux/ptrace.h>
19 
20 #include <asm/pgtable.h>
21 
22 /*
23  * This routine handles page faults. It determines the problem, and
24  * then passes it off to one of the appropriate routines.
25  *
26  * error_code:
27  * bit 0 == 0 means no page found, 1 means protection fault
28  * bit 1 == 0 means read, 1 means write
29  *
30  * If this routine detects a bad access, it returns 1, otherwise it
31  * returns 0.
32  */
33 asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
34  unsigned long error_code)
35 {
36 #ifdef DEBUG
37  printk ("regs->sr=%#x, regs->pc=%#lx, address=%#lx, %ld\n",
38  regs->sr, regs->pc, address, error_code);
39 #endif
40 
41 /*
42  * Oops. The kernel tried to access some bad page. We'll have to
43  * terminate things with extreme prejudice.
44  */
45  if ((unsigned long) address < PAGE_SIZE) {
46  printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
47  } else
48  printk(KERN_ALERT "Unable to handle kernel access");
49  printk(" at virtual address %08lx\n",address);
50  if (!user_mode(regs))
51  die("Oops", regs, error_code);
53 
54  return 1;
55 }
56