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torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/arch/x86/lib/bhi.S
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/* SPDX-License-Identifier: GPL-2.0 */

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#include <linux/linkage.h>

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#include <asm/unwind_hints.h>

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#include <asm/nospec-branch.h>

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/*

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 * Notably, the FineIBT preamble calling these will have ZF set and r10 zero.

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 *

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 * The very last element is in fact larger than 32 bytes, but since its the

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 * last element, this does not matter,

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 *

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 * There are 2 #UD sites, located between 0,1-2,3 and 4,5-6,7 such that they

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 * can be reached using Jcc.d8, these elements (1 and 5) have sufficiently

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 * big alignment holes for this to not stagger the array.

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 */

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.pushsection .noinstr.text, "ax"

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	.align 32

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SYM_CODE_START(__bhi_args)

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#ifdef CONFIG_FINEIBT_BHI

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	.align 32

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SYM_INNER_LABEL(__bhi_args_0, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_1

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_1, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_1

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	cmovne %r10, %rdi

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 8

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	ANNOTATE_REACHABLE

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.Lud_1:	ud2

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_2, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_1

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_3, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_1

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	cmovne %r10, %rdx

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_4, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_2

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	cmovne %r10, %rdx

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	cmovne %r10, %rcx

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_5, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_2

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	cmovne %r10, %rdx

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	cmovne %r10, %rcx

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	cmovne %r10, %r8

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 8

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	ANNOTATE_REACHABLE

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.Lud_2:	ud2

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_6, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_2

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	cmovne %r10, %rdx

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	cmovne %r10, %rcx

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	cmovne %r10, %r8

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	cmovne %r10, %r9

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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	.align 32

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SYM_INNER_LABEL(__bhi_args_7, SYM_L_LOCAL)

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	ANNOTATE_NOENDBR

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	UNWIND_HINT_FUNC

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	jne .Lud_2

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	cmovne %r10, %rdi

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	cmovne %r10, %rsi

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	cmovne %r10, %rdx

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	cmovne %r10, %rcx

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	cmovne %r10, %r8

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	cmovne %r10, %r9

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	cmovne %r10, %rsp

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	ANNOTATE_UNRET_SAFE

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	ret

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	int3

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#endif /* CONFIG_FINEIBT_BHI */

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	.align 32

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SYM_INNER_LABEL(__bhi_args_end, SYM_L_GLOBAL)

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	ANNOTATE_NOENDBR

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	nop /* Work around toolchain+objtool quirk */

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SYM_CODE_END(__bhi_args)

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.popsection

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