+static void dump_mem(const char *str, const char *log_lvl,
+ unsigned long bottom, unsigned long top)
+{
+ unsigned long p;
+ int i;
+
+ printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top);
+
+ for (p = bottom & ~31; p < top; ) {
+ printk("%s%04lx: ", log_lvl, p & 0xffff);
+
+ for (i = 0; i < 8; i++, p += 4) {
+ unsigned int val;
+
+ if (p < bottom || p >= top)
+ printk(" ");
+ else {
+ if (__get_user(val, (unsigned int __user *)p)) {
+ printk("\n");
+ goto out;
+ }
+ printk("%08x ", val);
+ }
+ }
+ printk("\n");
+ }
+
+out:
+ return;
+}
+
+static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p)
+{
+ return (p > (unsigned long)tinfo)
+ && (p < (unsigned long)tinfo + THREAD_SIZE - 3);
+}
+
+#ifdef CONFIG_FRAME_POINTER
+static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ unsigned long lr, fp;
+ struct thread_info *tinfo;
+
+ if (regs)
+ fp = regs->r7;
+ else if (tsk == current)
+ asm("mov %0, r7" : "=r"(fp));
+ else
+ fp = tsk->thread.cpu_context.r7;
+
+ /*
+ * Walk the stack as long as the frame pointer (a) is within
+ * the kernel stack of the task, and (b) it doesn't move
+ * downwards.
+ */
+ tinfo = task_thread_info(tsk);
+ printk("%sCall trace:\n", log_lvl);
+ while (valid_stack_ptr(tinfo, fp)) {
+ unsigned long new_fp;
+
+ lr = *(unsigned long *)fp;
+#ifdef CONFIG_KALLSYMS
+ printk("%s [<%08lx>] ", log_lvl, lr);
+#else
+ printk(" [<%08lx>] ", lr);
+#endif
+ print_symbol("%s\n", lr);
+
+ new_fp = *(unsigned long *)(fp + 4);
+ if (new_fp <= fp)
+ break;
+ fp = new_fp;
+ }
+ printk("\n");
+}
+#else
+static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ unsigned long addr;
+
+ printk("%sCall trace:\n", log_lvl);
+
+ while (!kstack_end(sp)) {
+ addr = *sp++;
+ if (kernel_text_address(addr)) {
+#ifdef CONFIG_KALLSYMS
+ printk("%s [<%08lx>] ", log_lvl, addr);
+#else
+ printk(" [<%08lx>] ", addr);
+#endif
+ print_symbol("%s\n", addr);
+ }
+ }
+ printk("\n");
+}
+#endif
+
+void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ struct thread_info *tinfo;
+
+ if (sp == 0) {
+ if (tsk)
+ sp = tsk->thread.cpu_context.ksp;
+ else
+ sp = (unsigned long)&tinfo;
+ }
+ if (!tsk)
+ tsk = current;
+
+ tinfo = task_thread_info(tsk);
+
+ if (valid_stack_ptr(tinfo, sp)) {
+ dump_mem("Stack: ", log_lvl, sp,
+ THREAD_SIZE + (unsigned long)tinfo);
+ show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl);
+ }
+}
+
+void show_stack(struct task_struct *tsk, unsigned long *stack)
+{
+ show_stack_log_lvl(tsk, (unsigned long)stack, NULL, "");
+}
+
+void dump_stack(void)
+{
+ unsigned long stack;
+
+ show_trace_log_lvl(current, &stack, NULL, "");
+}
+EXPORT_SYMBOL(dump_stack);
+