arch/sh/kernel/dumpstack.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 1991, 1992  Linus Torvalds
   4  *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
   5  *  Copyright (C) 2009  Matt Fleming
   6  *  Copyright (C) 2002 - 2012  Paul Mundt
   7  */
   8 #include <linux/kallsyms.h>
   9 #include <linux/ftrace.h>
  10 #include <linux/debug_locks.h>
  11 #include <linux/sched/debug.h>
  12 #include <linux/sched/task_stack.h>
  13 #include <linux/kdebug.h>
  14 #include <linux/export.h>
  15 #include <linux/uaccess.h>
  16 #include <asm/unwinder.h>
  17 #include <asm/stacktrace.h>
  18
  19 void dump_mem(const char *str, unsigned long bottom, unsigned long top)
  20 {
  21         unsigned long p;
  22         int i;
  23
  24         printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
  25
  26         for (p = bottom & ~31; p < top; ) {
  27                 printk("%04lx: ", p & 0xffff);
  28
  29                 for (i = 0; i < 8; i++, p += 4) {
  30                         unsigned int val;
  31
  32                         if (p < bottom || p >= top)
  33                                 printk("         ");
  34                         else {
  35                                 if (__get_user(val, (unsigned int __user *)p)) {
  36                                         printk("\n");
  37                                         return;
  38                                 }
  39                                 printk("%08x ", val);
  40                         }
  41                 }
  42                 printk("\n");
  43         }
  44 }
  45
  46 void printk_address(unsigned long address, int reliable)
  47 {
  48         printk(" [<%p>] %s%pS\n", (void *) address,
  49                         reliable ? "" : "? ", (void *) address);
  50 }
  51
  52 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  53 static void
  54 print_ftrace_graph_addr(unsigned long addr, void *data,
  55                         const struct stacktrace_ops *ops,
  56                         struct thread_info *tinfo, int *graph)
  57 {
  58         struct task_struct *task = tinfo->task;
  59         struct ftrace_ret_stack *ret_stack;
  60         unsigned long ret_addr;
  61
  62         if (addr != (unsigned long)return_to_handler)
  63                 return;
  64
  65         if (!task->ret_stack)
  66                 return;
  67
  68         ret_stack = ftrace_graph_get_ret_stack(task, *graph);
  69         if (!ret_stack)
  70                 return;
  71
  72         ret_addr = ret_stack->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 }