LXR linux/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
  19void dump_mem(const char *str, const char *loglvl, unsigned long bottom,
  20              unsigned long top)
  21{
  22        unsigned long p;
  23        int i;
  24
  25        printk("%s%s(0x%08lx to 0x%08lx)\n", loglvl, str, bottom, top);
  26
  27        for (p = bottom & ~31; p < top; ) {
  28                printk("%s%04lx: ", loglvl,  p & 0xffff);
  29
  30                for (i = 0; i < 8; i++, p += 4) {
  31                        unsigned int val;
  32
  33                        if (p < bottom || p >= top)
  34                                pr_cont("         ");
  35                        else {
  36                                if (__get_user(val, (unsigned int __user *)p)) {
  37                                        pr_cont("\n");
  38                                        return;
  39                                }
  40                                pr_cont("%08x ", val);
  41                        }
  42                }
  43                pr_cont("\n");
  44        }
  45}
  46
  47void printk_address(unsigned long address, int reliable)
  48{
  49        pr_cont(" [<%px>] %s%pS\n", (void *) address,
  50                reliable ? "" : "? ", (void *) address);
  51}
  52
  53#ifdef CONFIG_FUNCTION_GRAPH_TRACER
  54static void
  55print_ftrace_graph_addr(unsigned long addr, void *data,
  56                        const struct stacktrace_ops *ops,
  57                        struct thread_info *tinfo, int *graph)
  58{
  59        struct task_struct *task = tinfo->task;
  60        struct ftrace_ret_stack *ret_stack;
  61        unsigned long ret_addr;
  62
  63        if (addr != (unsigned long)return_to_handler)
  64                return;
  65
  66        if (!task->ret_stack)
  67                return;
  68
  69        ret_stack = ftrace_graph_get_ret_stack(task, *graph);
  70        if (!ret_stack)
  71                return;
  72
  73        ret_addr = ret_stack->ret;
  74
  75        ops->address(data, ret_addr, 1);
  76
  77        (*graph)++;
  78}
  79#else
  80static inline void
  81print_ftrace_graph_addr(unsigned long addr, void *data,
  82                        const struct stacktrace_ops *ops,
  83                        struct thread_info *tinfo, int *graph)
  84{ }
  85#endif
  86
  87void
  88stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
  89                  unsigned long *sp, const struct stacktrace_ops *ops,
  90                  void *data)
  91{
  92        struct thread_info *context;
  93        int graph = 0;
  94
  95        context = (struct thread_info *)
  96                ((unsigned long)sp & (~(THREAD_SIZE - 1)));
  97
  98        while (!kstack_end(sp)) {
  99                unsigned long addr = *sp++;
 100
 101                if (__kernel_text_address(addr)) {
 102                        ops->address(data, addr, 1);
 103
 104                        print_ftrace_graph_addr(addr, data, ops,
 105                                                context, &graph);
 106                }
 107        }
 108}
 109
 110/*
 111 * Print one address/symbol entries per line.
 112 */
 113static void print_trace_address(void *data, unsigned long addr, int reliable)
 114{
 115        printk("%s", (char *)data);
 116        printk_address(addr, reliable);
 117}
 118
 119static const struct stacktrace_ops print_trace_ops = {
 120        .address = print_trace_address,
 121};
 122
 123void show_trace(struct task_struct *tsk, unsigned long *sp,
 124                struct pt_regs *regs, const char *loglvl)
 125{
 126        if (regs && user_mode(regs))
 127                return;
 128
 129        printk("%s\nCall trace:\n", loglvl);
 130
 131        unwind_stack(tsk, regs, sp, &print_trace_ops, (void *)loglvl);
 132
 133        pr_cont("\n");
 134
 135        if (!tsk)
 136                tsk = current;
 137
 138        debug_show_held_locks(tsk);
 139}
 140
 141void show_stack(struct task_struct *tsk, unsigned long *sp, const char *loglvl)
 142{
 143        unsigned long stack;
 144
 145        if (!tsk)
 146                tsk = current;
 147        if (tsk == current)
 148                sp = (unsigned long *)current_stack_pointer;
 149        else
 150                sp = (unsigned long *)tsk->thread.sp;
 151
 152        stack = (unsigned long)sp;
 153        dump_mem("Stack: ", loglvl, stack, THREAD_SIZE +
 154                 (unsigned long)task_stack_page(tsk));
 155        show_trace(tsk, sp, NULL, loglvl);
 156}
 157