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UefiCpuPkg/MpLib: Add GDTR, IDTR and TR in saved AP data 

In current implementation of CPU MP service, AP is initialized with data
copied from BSP. Stack switch required by Stack Guard feature needs different
GDT, IDT table and task gates for each logic processor. This patch adds GDTR,
IDTR and TR into structure CPU_VOLATILE_REGISTERS and related code in save
and restore methods. This can make sure that any changes to GDT, IDT and task
gate for an AP will be kept from overwritten by BSP settings.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Jeff Fan <vanjeff_919@hotmail.com>
Reviewed-by: Jiewen.yao@intel.com
This commit is contained in:
Jian J Wang 2017-12-07 20:16:29 +08:00 committed by Star Zeng
parent 4cb21e1e72
commit e9415e4846
2 changed files with 20 additions and 0 deletions
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17
UefiCpuPkg/Library/MpInitLib/MpLib.c
View File

@ -195,6 +195,10 @@ SaveVolatileRegisters (
VolatileRegisters->Dr6 = AsmReadDr6 ();
VolatileRegisters->Dr7 = AsmReadDr7 ();
}
AsmReadGdtr (&VolatileRegisters->Gdtr);
AsmReadIdtr (&VolatileRegisters->Idtr);
VolatileRegisters->Tr = AsmReadTr ();
}
/**
@ -211,6 +215,7 @@ RestoreVolatileRegisters (
)
{
CPUID_VERSION_INFO_EDX VersionInfoEdx;
IA32_TSS_DESCRIPTOR *Tss;
AsmWriteCr0 (VolatileRegisters->Cr0);
AsmWriteCr3 (VolatileRegisters->Cr3);
@ -231,6 +236,18 @@ RestoreVolatileRegisters (
AsmWriteDr7 (VolatileRegisters->Dr7);
}
}
AsmWriteGdtr (&VolatileRegisters->Gdtr);
AsmWriteIdtr (&VolatileRegisters->Idtr);
if (VolatileRegisters->Tr != 0 &&
VolatileRegisters->Tr < VolatileRegisters->Gdtr.Limit) {
Tss = (IA32_TSS_DESCRIPTOR *)(VolatileRegisters->Gdtr.Base +
VolatileRegisters->Tr);
if (Tss->Bits.P == 1) {
Tss->Bits.Type &= 0xD; // 1101 - Clear busy bit just in case
AsmWriteTr (VolatileRegisters->Tr);
}
}
}
/**

3
UefiCpuPkg/Library/MpInitLib/MpLib.h
View File

@ -102,6 +102,9 @@ typedef struct {
UINTN Dr3;
UINTN Dr6;
UINTN Dr7;
IA32_DESCRIPTOR Gdtr;
IA32_DESCRIPTOR Idtr;
UINT16 Tr;
} CPU_VOLATILE_REGISTERS;
//