1 /*
2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
4 * Copyright (C) 2009 Matt Fleming
5 */
6 #include <linux/kallsyms.h>
7 #include <linux/ftrace.h>
8 #include <linux/debug_locks.h>
9 #include <asm/unwinder.h>
10 #include <asm/stacktrace.h>
11
printk_address(unsigned long address,int reliable)12 void printk_address(unsigned long address, int reliable)
13 {
14 printk(" [<%p>] %s%pS\n", (void *) address,
15 reliable ? "" : "? ", (void *) address);
16 }
17
18 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
19 static void
print_ftrace_graph_addr(unsigned long addr,void * data,const struct stacktrace_ops * ops,struct thread_info * tinfo,int * graph)20 print_ftrace_graph_addr(unsigned long addr, void *data,
21 const struct stacktrace_ops *ops,
22 struct thread_info *tinfo, int *graph)
23 {
24 struct task_struct *task = tinfo->task;
25 unsigned long ret_addr;
26 int index = task->curr_ret_stack;
27
28 if (addr != (unsigned long)return_to_handler)
29 return;
30
31 if (!task->ret_stack || index < *graph)
32 return;
33
34 index -= *graph;
35 ret_addr = task->ret_stack[index].ret;
36
37 ops->address(data, ret_addr, 1);
38
39 (*graph)++;
40 }
41 #else
42 static inline void
print_ftrace_graph_addr(unsigned long addr,void * data,const struct stacktrace_ops * ops,struct thread_info * tinfo,int * graph)43 print_ftrace_graph_addr(unsigned long addr, void *data,
44 const struct stacktrace_ops *ops,
45 struct thread_info *tinfo, int *graph)
46 { }
47 #endif
48
49 void
stack_reader_dump(struct task_struct * task,struct pt_regs * regs,unsigned long * sp,const struct stacktrace_ops * ops,void * data)50 stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
51 unsigned long *sp, const struct stacktrace_ops *ops,
52 void *data)
53 {
54 struct thread_info *context;
55 int graph = 0;
56
57 context = (struct thread_info *)
58 ((unsigned long)sp & (~(THREAD_SIZE - 1)));
59
60 while (!kstack_end(sp)) {
61 unsigned long addr = *sp++;
62
63 if (__kernel_text_address(addr)) {
64 ops->address(data, addr, 1);
65
66 print_ftrace_graph_addr(addr, data, ops,
67 context, &graph);
68 }
69 }
70 }
71
print_trace_stack(void * data,char * name)72 static int print_trace_stack(void *data, char *name)
73 {
74 printk("%s <%s> ", (char *)data, name);
75 return 0;
76 }
77
78 /*
79 * Print one address/symbol entries per line.
80 */
print_trace_address(void * data,unsigned long addr,int reliable)81 static void print_trace_address(void *data, unsigned long addr, int reliable)
82 {
83 printk(data);
84 printk_address(addr, reliable);
85 }
86
87 static const struct stacktrace_ops print_trace_ops = {
88 .stack = print_trace_stack,
89 .address = print_trace_address,
90 };
91
show_trace(struct task_struct * tsk,unsigned long * sp,struct pt_regs * regs)92 void show_trace(struct task_struct *tsk, unsigned long *sp,
93 struct pt_regs *regs)
94 {
95 if (regs && user_mode(regs))
96 return;
97
98 printk("\nCall trace:\n");
99
100 unwind_stack(tsk, regs, sp, &print_trace_ops, "");
101
102 printk("\n");
103
104 if (!tsk)
105 tsk = current;
106
107 debug_show_held_locks(tsk);
108 }
109