[mirror_edk2.git] / UefiCpuPkg / PiSmmCpuDxeSmm / Ia32 / Cet.nasm

;------------------------------------------------------------------------------ ;\r
; Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>\r
; SPDX-License-Identifier: BSD-2-Clause-Patent\r
;\r
;-------------------------------------------------------------------------------\r
\r
%include "Nasm.inc"\r
\r
SECTION .text\r
\r
global ASM_PFX(DisableCet)\r
ASM_PFX(DisableCet):\r
\r
    ; Skip the pushed data for call\r
    mov     eax, 1\r
    incsspd eax\r
\r
    mov     eax, cr4\r
    btr     eax, 23                      ; clear CET\r
    mov     cr4, eax\r
    ret\r
\r
global ASM_PFX(EnableCet)\r
ASM_PFX(EnableCet):\r
\r
    mov     eax, cr4\r
    bts     eax, 23                      ; set CET\r
    mov     cr4, eax\r
\r
    ; use jmp to skip the check for ret\r
    pop     eax\r
    jmp     eax\r
\r
Commit	Line	Data
	1	;------------------------------------------------------------------------------ ;\r
	2	; Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>\r
	3	; SPDX-License-Identifier: BSD-2-Clause-Patent\r
	4	;\r
	5	;-------------------------------------------------------------------------------\r
	6	\r
	7	%include "Nasm.inc"\r
	8	\r
	9	SECTION .text\r
	10	\r
	11	global ASM_PFX(DisableCet)\r
	12	ASM_PFX(DisableCet):\r
	13	\r
	14	; Skip the pushed data for call\r
	15	mov eax, 1\r
	16	incsspd eax\r
	17	\r
	18	mov eax, cr4\r
	19	btr eax, 23 ; clear CET\r
	20	mov cr4, eax\r
	21	ret\r
	22	\r
	23	global ASM_PFX(EnableCet)\r
	24	ASM_PFX(EnableCet):\r
	25	\r
	26	mov eax, cr4\r
	27	bts eax, 23 ; set CET\r
	28	mov cr4, eax\r
	29	\r
	30	; use jmp to skip the check for ret\r
	31	pop eax\r
	32	jmp eax\r
	33	\r