2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
5 #include <linux/kallsyms.h>
6 #include <linux/kprobes.h>
7 #include <linux/uaccess.h>
8 #include <linux/hardirq.h>
9 #include <linux/kdebug.h>
10 #include <linux/export.h>
11 #include <linux/ptrace.h>
12 #include <linux/kexec.h>
13 #include <linux/sysfs.h>
14 #include <linux/bug.h>
15 #include <linux/nmi.h>
17 #include <asm/stacktrace.h>
19 void stack_type_str(enum stack_type type, const char **begin, const char **end)
23 case STACK_TYPE_SOFTIRQ:
33 static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info)
35 unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack);
36 unsigned long *end = begin + (THREAD_SIZE / sizeof(long));
39 * This is a software stack, so 'end' can be a valid stack pointer.
40 * It just means the stack is empty.
42 if (stack < begin || stack > end)
45 info->type = STACK_TYPE_IRQ;
50 * See irq_32.c -- the next stack pointer is stored at the beginning of
53 info->next_sp = (unsigned long *)*begin;
58 static bool in_softirq_stack(unsigned long *stack, struct stack_info *info)
60 unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack);
61 unsigned long *end = begin + (THREAD_SIZE / sizeof(long));
64 * This is a software stack, so 'end' can be a valid stack pointer.
65 * It just means the stack is empty.
67 if (stack < begin || stack > end)
70 info->type = STACK_TYPE_SOFTIRQ;
75 * The next stack pointer is stored at the beginning of the stack.
78 info->next_sp = (unsigned long *)*begin;
83 int get_stack_info(unsigned long *stack, struct task_struct *task,
84 struct stack_info *info, unsigned long *visit_mask)
89 task = task ? : current;
91 if (in_task_stack(stack, task, info))
97 if (in_hardirq_stack(stack, info))
100 if (in_softirq_stack(stack, info))
101 goto recursion_check;
107 * Make sure we don't iterate through any given stack more than once.
108 * If it comes up a second time then there's something wrong going on:
109 * just break out and report an unknown stack type.
112 if (*visit_mask & (1UL << info->type))
114 *visit_mask |= 1UL << info->type;
120 info->type = STACK_TYPE_UNKNOWN;
124 void dump_trace(struct task_struct *task, struct pt_regs *regs,
125 unsigned long *stack, unsigned long bp,
126 const struct stacktrace_ops *ops, void *data)
128 unsigned long visit_mask = 0;
131 task = task ? : current;
132 stack = stack ? : get_stack_pointer(task, regs);
133 bp = bp ? : (unsigned long)get_frame_pointer(task, regs);
136 const char *begin_str, *end_str;
137 struct stack_info info;
139 if (get_stack_info(stack, task, &info, &visit_mask))
142 stack_type_str(info.type, &begin_str, &end_str);
144 if (begin_str && ops->stack(data, begin_str) < 0)
147 bp = ops->walk_stack(task, stack, bp, ops, data, &info, &graph);
149 if (end_str && ops->stack(data, end_str) < 0)
152 stack = info.next_sp;
154 touch_nmi_watchdog();
157 EXPORT_SYMBOL(dump_trace);
160 show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
161 unsigned long *sp, unsigned long bp, char *log_lvl)
163 unsigned long *stack;
166 if (!try_get_task_stack(task))
169 sp = sp ? : get_stack_pointer(task, regs);
172 for (i = 0; i < kstack_depth_to_print; i++) {
173 if (kstack_end(stack))
175 if ((i % STACKSLOTS_PER_LINE) == 0) {
178 printk("%s %08lx", log_lvl, *stack++);
180 pr_cont(" %08lx", *stack++);
181 touch_nmi_watchdog();
184 show_trace_log_lvl(task, regs, sp, bp, log_lvl);
186 put_task_stack(task);
190 void show_regs(struct pt_regs *regs)
194 show_regs_print_info(KERN_EMERG);
195 __show_regs(regs, !user_mode(regs));
198 * When in-kernel, we also print out the stack and code at the
199 * time of the fault..
201 if (!user_mode(regs)) {
202 unsigned int code_prologue = code_bytes * 43 / 64;
203 unsigned int code_len = code_bytes;
207 pr_emerg("Stack:\n");
208 show_stack_log_lvl(NULL, regs, NULL, 0, KERN_EMERG);
212 ip = (u8 *)regs->ip - code_prologue;
213 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
214 /* try starting at IP */
216 code_len = code_len - code_prologue + 1;
218 for (i = 0; i < code_len; i++, ip++) {
219 if (ip < (u8 *)PAGE_OFFSET ||
220 probe_kernel_address(ip, c)) {
221 pr_cont(" Bad EIP value.");
224 if (ip == (u8 *)regs->ip)
225 pr_cont(" <%02x>", c);
233 int is_valid_bugaddr(unsigned long ip)
237 if (ip < PAGE_OFFSET)
239 if (probe_kernel_address((unsigned short *)ip, ud2))
242 return ud2 == 0x0b0f;