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1#ifndef _ASM_X86_UNWIND_HINTS_H
2#define _ASM_X86_UNWIND_HINTS_H
3
4#include <linux/objtool.h>
5
6#include "orc_types.h"
7
8#ifdef __ASSEMBLY__
9
10.macro UNWIND_HINT_EMPTY
11 UNWIND_HINT type=UNWIND_HINT_TYPE_CALL end=1
12.endm
13
14.macro UNWIND_HINT_ENTRY
15 UNWIND_HINT type=UNWIND_HINT_TYPE_ENTRY end=1
16.endm
17
18.macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 partial=0
19 .if \base == %rsp
20 .if \indirect
21 .set sp_reg, ORC_REG_SP_INDIRECT
22 .else
23 .set sp_reg, ORC_REG_SP
24 .endif
25 .elseif \base == %rbp
26 .set sp_reg, ORC_REG_BP
27 .elseif \base == %rdi
28 .set sp_reg, ORC_REG_DI
29 .elseif \base == %rdx
30 .set sp_reg, ORC_REG_DX
31 .elseif \base == %r10
32 .set sp_reg, ORC_REG_R10
33 .else
34 .error "UNWIND_HINT_REGS: bad base register"
35 .endif
36
37 .set sp_offset, \offset
38
39 .if \partial
40 .set type, UNWIND_HINT_TYPE_REGS_PARTIAL
41 .elseif \extra == 0
42 .set type, UNWIND_HINT_TYPE_REGS_PARTIAL
43 .set sp_offset, \offset + (16*8)
44 .else
45 .set type, UNWIND_HINT_TYPE_REGS
46 .endif
47
48 UNWIND_HINT sp_reg=sp_reg sp_offset=sp_offset type=type
49.endm
50
51.macro UNWIND_HINT_IRET_REGS base=%rsp offset=0
52 UNWIND_HINT_REGS base=\base offset=\offset partial=1
53.endm
54
55.macro UNWIND_HINT_FUNC
56 UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=8 type=UNWIND_HINT_TYPE_FUNC
57.endm
58
59.macro UNWIND_HINT_SAVE
60 UNWIND_HINT type=UNWIND_HINT_TYPE_SAVE
61.endm
62
63.macro UNWIND_HINT_RESTORE
64 UNWIND_HINT type=UNWIND_HINT_TYPE_RESTORE
65.endm
66
67#else
68
69#define UNWIND_HINT_FUNC \
70 UNWIND_HINT(ORC_REG_SP, 8, UNWIND_HINT_TYPE_FUNC, 0)
71
72#endif /* __ASSEMBLY__ */
73
74#endif /* _ASM_X86_UNWIND_HINTS_H */
1#ifndef _ASM_X86_UNWIND_HINTS_H
2#define _ASM_X86_UNWIND_HINTS_H
3
4#include "orc_types.h"
5
6#ifdef __ASSEMBLY__
7
8/*
9 * In asm, there are two kinds of code: normal C-type callable functions and
10 * the rest. The normal callable functions can be called by other code, and
11 * don't do anything unusual with the stack. Such normal callable functions
12 * are annotated with the ENTRY/ENDPROC macros. Most asm code falls in this
13 * category. In this case, no special debugging annotations are needed because
14 * objtool can automatically generate the ORC data for the ORC unwinder to read
15 * at runtime.
16 *
17 * Anything which doesn't fall into the above category, such as syscall and
18 * interrupt handlers, tends to not be called directly by other functions, and
19 * often does unusual non-C-function-type things with the stack pointer. Such
20 * code needs to be annotated such that objtool can understand it. The
21 * following CFI hint macros are for this type of code.
22 *
23 * These macros provide hints to objtool about the state of the stack at each
24 * instruction. Objtool starts from the hints and follows the code flow,
25 * making automatic CFI adjustments when it sees pushes and pops, filling out
26 * the debuginfo as necessary. It will also warn if it sees any
27 * inconsistencies.
28 */
29.macro UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=0 type=ORC_TYPE_CALL end=0
30#ifdef CONFIG_STACK_VALIDATION
31.Lunwind_hint_ip_\@:
32 .pushsection .discard.unwind_hints
33 /* struct unwind_hint */
34 .long .Lunwind_hint_ip_\@ - .
35 .short \sp_offset
36 .byte \sp_reg
37 .byte \type
38 .byte \end
39 .balign 4
40 .popsection
41#endif
42.endm
43
44.macro UNWIND_HINT_EMPTY
45 UNWIND_HINT sp_reg=ORC_REG_UNDEFINED end=1
46.endm
47
48.macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 iret=0
49 .if \base == %rsp
50 .if \indirect
51 .set sp_reg, ORC_REG_SP_INDIRECT
52 .else
53 .set sp_reg, ORC_REG_SP
54 .endif
55 .elseif \base == %rbp
56 .set sp_reg, ORC_REG_BP
57 .elseif \base == %rdi
58 .set sp_reg, ORC_REG_DI
59 .elseif \base == %rdx
60 .set sp_reg, ORC_REG_DX
61 .elseif \base == %r10
62 .set sp_reg, ORC_REG_R10
63 .else
64 .error "UNWIND_HINT_REGS: bad base register"
65 .endif
66
67 .set sp_offset, \offset
68
69 .if \iret
70 .set type, ORC_TYPE_REGS_IRET
71 .elseif \extra == 0
72 .set type, ORC_TYPE_REGS_IRET
73 .set sp_offset, \offset + (16*8)
74 .else
75 .set type, ORC_TYPE_REGS
76 .endif
77
78 UNWIND_HINT sp_reg=sp_reg sp_offset=sp_offset type=type
79.endm
80
81.macro UNWIND_HINT_IRET_REGS base=%rsp offset=0
82 UNWIND_HINT_REGS base=\base offset=\offset iret=1
83.endm
84
85.macro UNWIND_HINT_FUNC sp_offset=8
86 UNWIND_HINT sp_offset=\sp_offset
87.endm
88
89/*
90 * RET_OFFSET: Used on instructions that terminate a function; mostly RETURN
91 * and sibling calls. On these, sp_offset denotes the expected offset from
92 * initial_func_cfi.
93 */
94.macro UNWIND_HINT_RET_OFFSET sp_offset=8
95 UNWIND_HINT type=UNWIND_HINT_TYPE_RET_OFFSET sp_offset=\sp_offset
96.endm
97
98#endif /* __ASSEMBLY__ */
99
100#endif /* _ASM_X86_UNWIND_HINTS_H */