1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _ASM_X86_FRAME_H
  3#define _ASM_X86_FRAME_H
  4
  5#include <asm/asm.h>
  6
  7/*
  8 * These are stack frame creation macros.  They should be used by every
  9 * callable non-leaf asm function to make kernel stack traces more reliable.
 10 */
 11
 12#ifdef CONFIG_FRAME_POINTER
 13
 14#ifdef __ASSEMBLY__
 15
 16.macro FRAME_BEGIN
 17	push %_ASM_BP
 18	_ASM_MOV %_ASM_SP, %_ASM_BP
 19.endm
 20
 21.macro FRAME_END
 22	pop %_ASM_BP
 23.endm
 24
 25#ifdef CONFIG_X86_64
 26/*
 27 * This is a sneaky trick to help the unwinder find pt_regs on the stack.  The
 28 * frame pointer is replaced with an encoded pointer to pt_regs.  The encoding
 29 * is just setting the LSB, which makes it an invalid stack address and is also
 30 * a signal to the unwinder that it's a pt_regs pointer in disguise.
 31 *
 32 * NOTE: This macro must be used *after* PUSH_AND_CLEAR_REGS because it corrupts
 33 * the original rbp.
 34 */
 35.macro ENCODE_FRAME_POINTER ptregs_offset=0
 36	leaq 1+\ptregs_offset(%rsp), %rbp
 37.endm
 38#else /* !CONFIG_X86_64 */
 39/*
 40 * This is a sneaky trick to help the unwinder find pt_regs on the stack.  The
 41 * frame pointer is replaced with an encoded pointer to pt_regs.  The encoding
 42 * is just clearing the MSB, which makes it an invalid stack address and is also
 43 * a signal to the unwinder that it's a pt_regs pointer in disguise.
 44 *
 45 * NOTE: This macro must be used *after* SAVE_ALL because it corrupts the
 46 * original ebp.
 47 */
 48.macro ENCODE_FRAME_POINTER
 49	mov %esp, %ebp
 50	andl $0x7fffffff, %ebp
 51.endm
 52#endif /* CONFIG_X86_64 */
 53
 54#else /* !__ASSEMBLY__ */
 55
 56#define FRAME_BEGIN				\
 57	"push %" _ASM_BP "\n"			\
 58	_ASM_MOV "%" _ASM_SP ", %" _ASM_BP "\n"
 59
 60#define FRAME_END "pop %" _ASM_BP "\n"
 61
 62#ifdef CONFIG_X86_64
 63
 64#define ENCODE_FRAME_POINTER			\
 65	"lea 1(%rsp), %rbp\n\t"
 66
 67static inline unsigned long encode_frame_pointer(struct pt_regs *regs)
 68{
 69	return (unsigned long)regs + 1;
 70}
 71
 72#else /* !CONFIG_X86_64 */
 73
 74#define ENCODE_FRAME_POINTER			\
 75	"movl %esp, %ebp\n\t"			\
 76	"andl $0x7fffffff, %ebp\n\t"
 77
 78static inline unsigned long encode_frame_pointer(struct pt_regs *regs)
 79{
 80	return (unsigned long)regs & 0x7fffffff;
 81}
 82
 83#endif /* CONFIG_X86_64 */
 84
 85#endif /* __ASSEMBLY__ */
 86
 87#define FRAME_OFFSET __ASM_SEL(4, 8)
 88
 89#else /* !CONFIG_FRAME_POINTER */
 90
 91#ifdef __ASSEMBLY__
 92
 93.macro ENCODE_FRAME_POINTER ptregs_offset=0
 94.endm
 95
 96#else /* !__ASSEMBLY */
 97
 98#define ENCODE_FRAME_POINTER
 99
100static inline unsigned long encode_frame_pointer(struct pt_regs *regs)
101{
102	return 0;
103}
104
105#endif
106
107#define FRAME_BEGIN
108#define FRAME_END
109#define FRAME_OFFSET 0
110
111#endif /* CONFIG_FRAME_POINTER */
112
113#endif /* _ASM_X86_FRAME_H */

 
 1#ifndef _ASM_X86_FRAME_H
 2#define _ASM_X86_FRAME_H
 3
 4#include <asm/asm.h>
 5
 6/*
 7 * These are stack frame creation macros.  They should be used by every
 8 * callable non-leaf asm function to make kernel stack traces more reliable.
 9 */
10
11#ifdef CONFIG_FRAME_POINTER
12
13#ifdef __ASSEMBLY__
14
15.macro FRAME_BEGIN
16	push %_ASM_BP
17	_ASM_MOV %_ASM_SP, %_ASM_BP
18.endm
19
20.macro FRAME_END
21	pop %_ASM_BP
22.endm
23
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
24#else /* !__ASSEMBLY__ */
25
26#define FRAME_BEGIN				\
27	"push %" _ASM_BP "\n"			\
28	_ASM_MOV "%" _ASM_SP ", %" _ASM_BP "\n"
29
30#define FRAME_END "pop %" _ASM_BP "\n"
31
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
32#endif /* __ASSEMBLY__ */
33
34#define FRAME_OFFSET __ASM_SEL(4, 8)
35
36#else /* !CONFIG_FRAME_POINTER */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
37
38#define FRAME_BEGIN
39#define FRAME_END
40#define FRAME_OFFSET 0
41
42#endif /* CONFIG_FRAME_POINTER */
43
44#endif /* _ASM_X86_FRAME_H */