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UefiCpuPkg: PiSmmCpuDxeSmm skip MSR_IA32_MISC_ENABLE manipulation on AMD

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AMD does not support MSR_IA32_MISC_ENABLE.  Accessing that register
causes and exception on AMD processors.  If Execution Disable is
supported, but if the processor is an AMD processor, skip manipulating
MSR_IA32_MISC_ENABLE[34] XD Disable bit.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Garrett Kirkendall <garrett.kirkendall@amd.com>
Message-Id: <20200622131825.1352-5-Garrett.Kirkendall@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
This commit is contained in:
Kirkendall, Garrett
2020-06-22 08:18:25 -05:00
committed by mergify[bot]
parent df667535ed
commit bdafda8c45
4 changed files with 46 additions and 5 deletions
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19
UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm
View File

@@ -1,5 +1,6 @@
;------------------------------------------------------------------------------ ;
; Copyright (c) 2016 - 2019, Intel Corporation. All rights reserved.<BR>
; Copyright (c) 2020, AMD Incorporated. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
@@ -59,6 +60,7 @@ global ASM_PFX(gPatchSmiStack)
global ASM_PFX(gPatchSmbase)
extern ASM_PFX(mXdSupported)
global ASM_PFX(gPatchXdSupported)
global ASM_PFX(gPatchMsrIa32MiscEnableSupported)
extern ASM_PFX(gSmiHandlerIdtr)
extern ASM_PFX(mCetSupported)
@@ -153,17 +155,30 @@ ASM_PFX(gPatchSmiCr3):
ASM_PFX(gPatchXdSupported):
cmp al, 0
jz @SkipXd
; If MSR_IA32_MISC_ENABLE is supported, clear XD Disable bit
mov al, strict byte 1 ; source operand may be patched
ASM_PFX(gPatchMsrIa32MiscEnableSupported):
cmp al, 1
jz MsrIa32MiscEnableSupported
; MSR_IA32_MISC_ENABLE not supported
xor edx, edx
push edx ; don't try to restore the XD Disable bit just before RSM
jmp EnableNxe
;
; Check XD disable bit
;
MsrIa32MiscEnableSupported:
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
push edx ; save MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2 ; MSR_IA32_MISC_ENABLE[34]
jz .5
jz EnableNxe
and dx, 0xFFFB ; clear XD Disable bit if it is set
wrmsr
.5:
EnableNxe:
mov ecx, MSR_EFER
rdmsr
or ax, MSR_EFER_XD ; enable NXE