1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Stack trace management functions 4 * 5 * Copyright (C) 2009 Helge Deller <deller@gmx.de> 6 * based on arch/x86/kernel/stacktrace.c by Ingo Molnar <mingo@redhat.com> 7 * and parisc unwind functions by Randolph Chung <tausq@debian.org> 8 * 9 * TODO: Userspace stacktrace (CONFIG_USER_STACKTRACE_SUPPORT) 10 */ 11 #include <linux/module.h> 12 #include <linux/stacktrace.h> 13 14 #include <asm/unwind.h> 15 16 static void dump_trace(struct task_struct *task, struct stack_trace *trace) 17 { 18 struct unwind_frame_info info; 19 20 unwind_frame_init_task(&info, task, NULL); 21 22 /* unwind stack and save entries in stack_trace struct */ 23 trace->nr_entries = 0; 24 while (trace->nr_entries < trace->max_entries) { 25 if (unwind_once(&info) < 0 || info.ip == 0) 26 break; 27 28 if (__kernel_text_address(info.ip)) 29 trace->entries[trace->nr_entries++] = info.ip; 30 } 31 } 32 33 /* 34 * Save stack-backtrace addresses into a stack_trace buffer. 35 */ 36 void save_stack_trace(struct stack_trace *trace) 37 { 38 dump_trace(current, trace); 39 } 40 EXPORT_SYMBOL_GPL(save_stack_trace); 41 42 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 43 { 44 dump_trace(tsk, trace); 45 } 46 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 47