Thomas Gleixner | d2912cb | 2019-06-04 10:11:33 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Daniel Walter | 970e51f | 2014-08-20 10:56:00 +0100 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
| 4 | * Copyright (C) 2013 Richard Weinberger <richard@nod.at> |
| 5 | * Copyright (C) 2014 Google Inc., Author: Daniel Walter <dwalter@google.com> |
Daniel Walter | 970e51f | 2014-08-20 10:56:00 +0100 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <linux/kallsyms.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/sched.h> |
| 11 | #include <linux/stacktrace.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/uaccess.h> |
| 14 | #include <asm/stacktrace.h> |
| 15 | |
| 16 | void dump_trace(struct task_struct *tsk, |
| 17 | const struct stacktrace_ops *ops, |
| 18 | void *data) |
| 19 | { |
| 20 | int reliable = 0; |
| 21 | unsigned long *sp, bp, addr; |
| 22 | struct pt_regs *segv_regs = tsk->thread.segv_regs; |
| 23 | struct stack_frame *frame; |
| 24 | |
| 25 | bp = get_frame_pointer(tsk, segv_regs); |
| 26 | sp = get_stack_pointer(tsk, segv_regs); |
| 27 | |
| 28 | frame = (struct stack_frame *)bp; |
| 29 | while (((long) sp & (THREAD_SIZE-1)) != 0) { |
| 30 | addr = *sp; |
| 31 | if (__kernel_text_address(addr)) { |
| 32 | reliable = 0; |
| 33 | if ((unsigned long) sp == bp + sizeof(long)) { |
| 34 | frame = frame ? frame->next_frame : NULL; |
| 35 | bp = (unsigned long)frame; |
| 36 | reliable = 1; |
| 37 | } |
| 38 | ops->address(data, addr, reliable); |
| 39 | } |
| 40 | sp++; |
| 41 | } |
| 42 | } |
| 43 | |
| 44 | static void save_addr(void *data, unsigned long address, int reliable) |
| 45 | { |
| 46 | struct stack_trace *trace = data; |
| 47 | |
| 48 | if (!reliable) |
| 49 | return; |
| 50 | if (trace->nr_entries >= trace->max_entries) |
| 51 | return; |
| 52 | |
| 53 | trace->entries[trace->nr_entries++] = address; |
| 54 | } |
| 55 | |
| 56 | static const struct stacktrace_ops dump_ops = { |
| 57 | .address = save_addr |
| 58 | }; |
| 59 | |
| 60 | static void __save_stack_trace(struct task_struct *tsk, struct stack_trace *trace) |
| 61 | { |
| 62 | dump_trace(tsk, &dump_ops, trace); |
Daniel Walter | 970e51f | 2014-08-20 10:56:00 +0100 | [diff] [blame] | 63 | } |
| 64 | |
| 65 | void save_stack_trace(struct stack_trace *trace) |
| 66 | { |
| 67 | __save_stack_trace(current, trace); |
| 68 | } |
| 69 | EXPORT_SYMBOL_GPL(save_stack_trace); |
| 70 | |
| 71 | void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) |
| 72 | { |
| 73 | __save_stack_trace(tsk, trace); |
| 74 | } |
| 75 | EXPORT_SYMBOL_GPL(save_stack_trace_tsk); |