arch/sh/kernel/dumpstack.c

   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  *  Copyright (C) 2002 - 2012  Paul Mundt
   6  *
   7  * This file is subject to the terms and conditions of the GNU General Public
   8  * License.  See the file "COPYING" in the main directory of this archive
   9  * for more details.
  10  */
  11 #include <linux/kallsyms.h>
  12 #include <linux/ftrace.h>
  13 #include <linux/debug_locks.h>
  14 #include <linux/sched/debug.h>
  15 #include <linux/sched/task_stack.h>
  16 #include <linux/kdebug.h>
  17 #include <linux/export.h>
  18 #include <linux/uaccess.h>
  19 #include <asm/unwinder.h>
  20 #include <asm/stacktrace.h>
  21
  22 void dump_mem(const char *str, unsigned long bottom, unsigned long top)
  23 {
  24         unsigned long p;
  25         int i;
  26
  27         printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
  28
  29         for (p = bottom & ~31; p < top; ) {
  30                 printk("%04lx: ", p & 0xffff);
  31
  32                 for (i = 0; i < 8; i++, p += 4) {
  33                         unsigned int val;
  34
  35                         if (p < bottom || p >= top)
  36                                 printk("         ");
  37                         else {
  38                                 if (__get_user(val, (unsigned int __user *)p)) {
  39                                         printk("\n");
  40                                         return;
  41                                 }
  42                                 printk("%08x ", val);
  43                         }
  44                 }
  45                 printk("\n");
  46         }
  47 }
  48
  49 void printk_address(unsigned long address, int reliable)
  50 {
  51         printk(" [<%p>] %s%pS\n", (void *) address,
  52                         reliable ? "" : "? ", (void *) address);
  53 }
  54
  55 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  56 static void
  57 print_ftrace_graph_addr(unsigned long addr, void *data,
  58                         const struct stacktrace_ops *ops,
  59                         struct thread_info *tinfo, int *graph)
  60 {
  61         struct task_struct *task = tinfo->task;
  62         unsigned long ret_addr;
  63         int index = task->curr_ret_stack;
  64
  65         if (addr != (unsigned long)return_to_handler)
  66                 return;
  67
  68         if (!task->ret_stack || index < *graph)
  69                 return;
  70
  71         index -= *graph;
  72         ret_addr = task->ret_stack[index].ret;
  73
  74         ops->address(data, ret_addr, 1);
  75
  76         (*graph)++;
  77 }
  78 #else
  79 static inline void
  80 print_ftrace_graph_addr(unsigned long addr, void *data,
  81                         const struct stacktrace_ops *ops,
  82                         struct thread_info *tinfo, int *graph)
  83 { }
  84 #endif
  85
  86 void
  87 stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
  88                   unsigned long *sp, const struct stacktrace_ops *ops,
  89                   void *data)
  90 {
  91         struct thread_info *context;
  92         int graph = 0;
  93
  94         context = (struct thread_info *)
  95                 ((unsigned long)sp & (~(THREAD_SIZE - 1)));
  96
  97         while (!kstack_end(sp)) {
  98                 unsigned long addr = *sp++;
  99
 100                 if (__kernel_text_address(addr)) {
 101                         ops->address(data, addr, 1);
 102
 103                         print_ftrace_graph_addr(addr, data, ops,
 104                                                 context, &graph);
 105                 }
 106         }
 107 }
 108
 109 static int print_trace_stack(void *data, char *name)
 110 {
 111         printk("%s <%s> ", (char *)data, name);
 112         return 0;
 113 }
 114
 115 /*
 116  * Print one address/symbol entries per line.
 117  */
 118 static void print_trace_address(void *data, unsigned long addr, int reliable)
 119 {
 120         printk("%s", (char *)data);
 121         printk_address(addr, reliable);
 122 }
 123
 124 static const struct stacktrace_ops print_trace_ops = {
 125         .stack = print_trace_stack,
 126         .address = print_trace_address,
 127 };
 128
 129 void show_trace(struct task_struct *tsk, unsigned long *sp,
 130                 struct pt_regs *regs)
 131 {
 132         if (regs && user_mode(regs))
 133                 return;
 134
 135         printk("\nCall trace:\n");
 136
 137         unwind_stack(tsk, regs, sp, &print_trace_ops, "");
 138
 139         printk("\n");
 140
 141         if (!tsk)
 142                 tsk = current;
 143
 144         debug_show_held_locks(tsk);
 145 }
 146
 147 void show_stack(struct task_struct *tsk, unsigned long *sp)
 148 {
 149         unsigned long stack;
 150
 151         if (!tsk)
 152                 tsk = current;
 153         if (tsk == current)
 154                 sp = (unsigned long *)current_stack_pointer;
 155         else
 156                 sp = (unsigned long *)tsk->thread.sp;
 157
 158         stack = (unsigned long)sp;
 159         dump_mem("Stack: ", stack, THREAD_SIZE +
 160                  (unsigned long)task_stack_page(tsk));
 161         show_trace(tsk, sp, NULL);
 162 }