1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_UNWIND_H
3 #define _ASM_X86_UNWIND_H
5 #include <linux/sched.h>
6 #include <linux/ftrace.h>
7 #include <asm/ptrace.h>
8 #include <asm/stacktrace.h>
10 #define IRET_FRAME_OFFSET (offsetof(struct pt_regs, ip))
11 #define IRET_FRAME_SIZE (sizeof(struct pt_regs) - IRET_FRAME_OFFSET)
14 struct stack_info stack_info
;
15 unsigned long stack_mask
;
16 struct task_struct
*task
;
19 #if defined(CONFIG_UNWINDER_ORC)
20 bool signal
, full_regs
;
21 unsigned long sp
, bp
, ip
;
23 #elif defined(CONFIG_UNWINDER_FRAME_POINTER)
25 unsigned long *bp
, *orig_sp
, ip
;
27 * If non-NULL: The current frame is incomplete and doesn't contain a
28 * valid BP. When looking for the next frame, use this instead of the
29 * non-existent saved BP.
31 unsigned long *next_bp
;
38 void __unwind_start(struct unwind_state
*state
, struct task_struct
*task
,
39 struct pt_regs
*regs
, unsigned long *first_frame
);
40 bool unwind_next_frame(struct unwind_state
*state
);
41 unsigned long unwind_get_return_address(struct unwind_state
*state
);
42 unsigned long *unwind_get_return_address_ptr(struct unwind_state
*state
);
44 static inline bool unwind_done(struct unwind_state
*state
)
46 return state
->stack_info
.type
== STACK_TYPE_UNKNOWN
;
49 static inline bool unwind_error(struct unwind_state
*state
)
55 void unwind_start(struct unwind_state
*state
, struct task_struct
*task
,
56 struct pt_regs
*regs
, unsigned long *first_frame
)
58 first_frame
= first_frame
? : get_stack_pointer(task
, regs
);
60 __unwind_start(state
, task
, regs
, first_frame
);
63 #if defined(CONFIG_UNWINDER_ORC) || defined(CONFIG_UNWINDER_FRAME_POINTER)
65 * If 'partial' returns true, only the iret frame registers are valid.
67 static inline struct pt_regs
*unwind_get_entry_regs(struct unwind_state
*state
,
70 if (unwind_done(state
))
74 #ifdef CONFIG_UNWINDER_ORC
75 *partial
= !state
->full_regs
;
84 static inline struct pt_regs
*unwind_get_entry_regs(struct unwind_state
*state
,
91 #ifdef CONFIG_UNWINDER_ORC
92 void unwind_init(void);
93 void unwind_module_init(struct module
*mod
, void *orc_ip
, size_t orc_ip_size
,
94 void *orc
, size_t orc_size
);
96 static inline void unwind_init(void) {}
98 void unwind_module_init(struct module
*mod
, void *orc_ip
, size_t orc_ip_size
,
99 void *orc
, size_t orc_size
) {}
103 * This disables KASAN checking when reading a value from another task's stack,
104 * since the other task could be running on another CPU and could have poisoned
105 * the stack in the meantime.
107 #define READ_ONCE_TASK_STACK(task, x) \
110 if (task == current) \
111 val = READ_ONCE(x); \
113 val = READ_ONCE_NOCHECK(x); \
117 static inline bool task_on_another_cpu(struct task_struct
*task
)
120 return task
!= current
&& task
->on_cpu
;
126 #endif /* _ASM_X86_UNWIND_H */