1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
6 #include <linux/sched/debug.h>
7 #include <linux/kallsyms.h>
8 #include <linux/kprobes.h>
9 #include <linux/uaccess.h>
10 #include <linux/hardirq.h>
11 #include <linux/kdebug.h>
12 #include <linux/export.h>
13 #include <linux/ptrace.h>
14 #include <linux/kexec.h>
15 #include <linux/sysfs.h>
16 #include <linux/bug.h>
17 #include <linux/nmi.h>
19 #include <asm/stacktrace.h>
21 const char *stack_type_name(enum stack_type type)
23 if (type == STACK_TYPE_IRQ)
26 if (type == STACK_TYPE_SOFTIRQ)
29 if (type == STACK_TYPE_ENTRY)
30 return "ENTRY_TRAMPOLINE";
35 static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info)
37 unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack_ptr);
38 unsigned long *end = begin + (THREAD_SIZE / sizeof(long));
41 * This is a software stack, so 'end' can be a valid stack pointer.
42 * It just means the stack is empty.
44 if (stack < begin || stack > end)
47 info->type = STACK_TYPE_IRQ;
52 * See irq_32.c -- the next stack pointer is stored at the beginning of
55 info->next_sp = (unsigned long *)*begin;
60 static bool in_softirq_stack(unsigned long *stack, struct stack_info *info)
62 unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack_ptr);
63 unsigned long *end = begin + (THREAD_SIZE / sizeof(long));
66 * This is a software stack, so 'end' can be a valid stack pointer.
67 * It just means the stack is empty.
69 if (stack < begin || stack > end)
72 info->type = STACK_TYPE_SOFTIRQ;
77 * The next stack pointer is stored at the beginning of the stack.
80 info->next_sp = (unsigned long *)*begin;
85 int get_stack_info(unsigned long *stack, struct task_struct *task,
86 struct stack_info *info, unsigned long *visit_mask)
91 task = task ? : current;
93 if (in_task_stack(stack, task, info))
99 if (in_entry_stack(stack, info))
100 goto recursion_check;
102 if (in_hardirq_stack(stack, info))
103 goto recursion_check;
105 if (in_softirq_stack(stack, info))
106 goto recursion_check;
112 * Make sure we don't iterate through any given stack more than once.
113 * If it comes up a second time then there's something wrong going on:
114 * just break out and report an unknown stack type.
117 if (*visit_mask & (1UL << info->type)) {
118 printk_deferred_once(KERN_WARNING "WARNING: stack recursion on stack type %d\n", info->type);
121 *visit_mask |= 1UL << info->type;
127 info->type = STACK_TYPE_UNKNOWN;