summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/dumpstack_32.c
blob: d593cd1f58dcca22925f10e2b3669435a4a25557 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
/*
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
 */
#include <linux/kallsyms.h>
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/utsname.h>
#include <linux/hardirq.h>
#include <linux/kdebug.h>
#include <linux/module.h>
#include <linux/ptrace.h>
#include <linux/kexec.h>
#include <linux/bug.h>
#include <linux/nmi.h>
#include <linux/sysfs.h>

#include <asm/stacktrace.h>

#include "dumpstack.h"

void dump_trace(struct task_struct *task, struct pt_regs *regs,
		unsigned long *stack, unsigned long bp,
		const struct stacktrace_ops *ops, void *data)
{
	int graph = 0;

	if (!task)
		task = current;

	if (!stack) {
		unsigned long dummy;
		stack = &dummy;
		if (task && task != current)
			stack = (unsigned long *)task->thread.sp;
	}

#ifdef CONFIG_FRAME_POINTER
	if (!bp) {
		if (task == current) {
			/* Grab bp right from our regs */
			get_bp(bp);
		} else {
			/* bp is the last reg pushed by switch_to */
			bp = *(unsigned long *) task->thread.sp;
		}
	}
#endif

	for (;;) {
		struct thread_info *context;

		context = (struct thread_info *)
			((unsigned long)stack & (~(THREAD_SIZE - 1)));
		bp = print_context_stack(context, stack, bp, ops,
					 data, NULL, &graph);

		stack = (unsigned long *)context->previous_esp;
		if (!stack)
			break;
		if (ops->stack(data, "IRQ") < 0)
			break;
		touch_nmi_watchdog();
	}
}
EXPORT_SYMBOL(dump_trace);

void
show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
		unsigned long *sp, unsigned long bp, char *log_lvl)
{
	unsigned long *stack;
	int i;

	if (sp == NULL) {
		if (task)
			sp = (unsigned long *)task->thread.sp;
		else
			sp = (unsigned long *)&sp;
	}

	stack = sp;
	for (i = 0; i < kstack_depth_to_print; i++) {
		if (kstack_end(stack))
			break;
		if (i && ((i % STACKSLOTS_PER_LINE) == 0))
			printk("\n%s", log_lvl);
		printk(" %08lx", *stack++);
		touch_nmi_watchdog();
	}
	printk("\n");
	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
}


void show_registers(struct pt_regs *regs)
{
	int i;

	print_modules();
	__show_regs(regs, 0);

	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n",
		TASK_COMM_LEN, current->comm, task_pid_nr(current),
		current_thread_info(), current, task_thread_info(current));
	/*
	 * When in-kernel, we also print out the stack and code at the
	 * time of the fault..
	 */
	if (!user_mode_vm(regs)) {
		unsigned int code_prologue = code_bytes * 43 / 64;
		unsigned int code_len = code_bytes;
		unsigned char c;
		u8 *ip;

		printk(KERN_EMERG "Stack:\n");
		show_stack_log_lvl(NULL, regs, &regs->sp,
				0, KERN_EMERG);

		printk(KERN_EMERG "Code: ");

		ip = (u8 *)regs->ip - code_prologue;
		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
			/* try starting at IP */
			ip = (u8 *)regs->ip;
			code_len = code_len - code_prologue + 1;
		}
		for (i = 0; i < code_len; i++, ip++) {
			if (ip < (u8 *)PAGE_OFFSET ||
					probe_kernel_address(ip, c)) {
				printk(" Bad EIP value.");
				break;
			}
			if (ip == (u8 *)regs->ip)
				printk("<%02x> ", c);
			else
				printk("%02x ", c);
		}
	}
	printk("\n");
}

int is_valid_bugaddr(unsigned long ip)
{
	unsigned short ud2;

	if (ip < PAGE_OFFSET)
		return 0;
	if (probe_kernel_address((unsigned short *)ip, ud2))
		return 0;

	return ud2 == 0x0b0f;
}