git.oblomov.eu Git - linux-2.6/blob - arch/x86/kernel/dumpstack_32.c

   1 /*
   2  *  Copyright (C) 1991, 1992  Linus Torvalds
   3  *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
   4  */
   5 #include <linux/kallsyms.h>
   6 #include <linux/kprobes.h>
   7 #include <linux/uaccess.h>
   8 #include <linux/utsname.h>
   9 #include <linux/hardirq.h>
  10 #include <linux/kdebug.h>
  11 #include <linux/module.h>
  12 #include <linux/ptrace.h>
  13 #include <linux/kexec.h>
  14 #include <linux/bug.h>
  15 #include <linux/nmi.h>
  16 #include <linux/sysfs.h>
  17
  18 #include <asm/stacktrace.h>
  19
  20 #include "dumpstack.h"
  21
  22 void dump_trace(struct task_struct *task, struct pt_regs *regs,
  23                 unsigned long *stack, unsigned long bp,
  24                 const struct stacktrace_ops *ops, void *data)
  25 {
  26         if (!task)
  27                 task = current;
  28
  29         if (!stack) {
  30                 unsigned long dummy;
  31                 stack = &dummy;
  32                 if (task && task != current)
  33                         stack = (unsigned long *)task->thread.sp;
  34         }
  35
  36 #ifdef CONFIG_FRAME_POINTER
  37         if (!bp) {
  38                 if (task == current) {
  39                         /* Grab bp right from our regs */
  40                         get_bp(bp);
  41                 } else {
  42                         /* bp is the last reg pushed by switch_to */
  43                         bp = *(unsigned long *) task->thread.sp;
  44                 }
  45         }
  46 #endif
  47
  48         for (;;) {
  49                 struct thread_info *context;
  50
  51                 context = (struct thread_info *)
  52                         ((unsigned long)stack & (~(THREAD_SIZE - 1)));
  53                 bp = print_context_stack(context, stack, bp, ops, data, NULL);
  54
  55                 stack = (unsigned long *)context->previous_esp;
  56                 if (!stack)
  57                         break;
  58                 if (ops->stack(data, "IRQ") < 0)
  59                         break;
  60                 touch_nmi_watchdog();
  61         }
  62 }
  63 EXPORT_SYMBOL(dump_trace);
  64
  65 void
  66 show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
  67                 unsigned long *sp, unsigned long bp, char *log_lvl)
  68 {
  69         unsigned long *stack;
  70         int i;
  71
  72         if (sp == NULL) {
  73                 if (task)
  74                         sp = (unsigned long *)task->thread.sp;
  75                 else
  76                         sp = (unsigned long *)&sp;
  77         }
  78
  79         stack = sp;
  80         for (i = 0; i < kstack_depth_to_print; i++) {
  81                 if (kstack_end(stack))
  82                         break;
  83                 if (i && ((i % STACKSLOTS_PER_LINE) == 0))
  84                         printk("\n%s", log_lvl);
  85                 printk(" %08lx", *stack++);
  86                 touch_nmi_watchdog();
  87         }
  88         printk("\n");
  89         show_trace_log_lvl(task, regs, sp, bp, log_lvl);
  90 }
  91
  92
  93 void show_registers(struct pt_regs *regs)
  94 {
  95         int i;
  96
  97         print_modules();
  98         __show_regs(regs, 0);
  99
 100         printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n",
 101                 TASK_COMM_LEN, current->comm, task_pid_nr(current),
 102                 current_thread_info(), current, task_thread_info(current));
 103         /*
 104          * When in-kernel, we also print out the stack and code at the
 105          * time of the fault..
 106          */
 107         if (!user_mode_vm(regs)) {
 108                 unsigned int code_prologue = code_bytes * 43 / 64;
 109                 unsigned int code_len = code_bytes;
 110                 unsigned char c;
 111                 u8 *ip;
 112
 113                 printk(KERN_EMERG "Stack:\n");
 114                 show_stack_log_lvl(NULL, regs, &regs->sp,
 115                                 0, KERN_EMERG);
 116
 117                 printk(KERN_EMERG "Code: ");
 118
 119                 ip = (u8 *)regs->ip - code_prologue;
 120                 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
 121                         /* try starting at IP */
 122                         ip = (u8 *)regs->ip;
 123                         code_len = code_len - code_prologue + 1;
 124                 }
 125                 for (i = 0; i < code_len; i++, ip++) {
 126                         if (ip < (u8 *)PAGE_OFFSET ||
 127                                         probe_kernel_address(ip, c)) {
 128                                 printk(" Bad EIP value.");
 129                                 break;
 130                         }
 131                         if (ip == (u8 *)regs->ip)
 132                                 printk("<%02x> ", c);
 133                         else
 134                                 printk("%02x ", c);
 135                 }
 136         }
 137         printk("\n");
 138 }
 139
 140 int is_valid_bugaddr(unsigned long ip)
 141 {
 142         unsigned short ud2;
 143
 144         if (ip < PAGE_OFFSET)
 145                 return 0;
 146         if (probe_kernel_address((unsigned short *)ip, ud2))
 147                 return 0;
 148
 149         return ud2 == 0x0b0f;
 150 }
 151