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UefiCpuPkg/MpInitLib: Fix potential issue when IDT table is at above 4G 

Currently, when waking up AP, IDT table of AP will be set in 16 bit code,
and assume the IDT table base is 32 bit. However, the IDT table is created
by BSP. Issue will happen if the BSP allocates memory above 4G for BSP's
IDT table. Moreover, even the IDT table location is below 4G, the handler
function inside the IDT table is 64 bit, and it won't take effect until
CPU transfers to 64 bit long mode. There is no benefit to set IDT table in
such an early phase.
To avoid such issue, this patch moves the LIDT instruction into 64 bit
code.

Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>
This commit is contained in:
Liu, Zhiguang 2022-08-25 10:55:04 +08:00 committed by mergify[bot]
parent 3c06953fd7
commit 367604b2f4
1 changed files with 5 additions and 3 deletions
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8
UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
View File

@ -64,9 +64,6 @@ BITS 16
mov si, MP_CPU_EXCHANGE_INFO_FIELD (GdtrProfile) mov si, MP_CPU_EXCHANGE_INFO_FIELD (GdtrProfile)
o32 lgdt [cs:si] o32 lgdt [cs:si]
mov si, MP_CPU_EXCHANGE_INFO_FIELD (IdtrProfile)
o32 lidt [cs:si]
; ;
; Switch to protected mode ; Switch to protected mode
; ;
@ -154,6 +151,11 @@ BITS 64
LongModeStart: LongModeStart:
mov esi, ebx mov esi, ebx
; Set IDT table at the start of 64 bit code
lea edi, [esi + MP_CPU_EXCHANGE_INFO_FIELD (IdtrProfile)]
lidt [edi]
lea edi, [esi + MP_CPU_EXCHANGE_INFO_FIELD (InitFlag)] lea edi, [esi + MP_CPU_EXCHANGE_INFO_FIELD (InitFlag)]
cmp qword [edi], 1 ; ApInitConfig cmp qword [edi], 1 ; ApInitConfig
jnz GetApicId jnz GetApicId