diff options
-rw-r--r-- | UefiCpuPkg/Library/MpInitLib/MpLib.c | 17 | ||||
-rw-r--r-- | UefiCpuPkg/Library/MpInitLib/MpLib.h | 3 |
2 files changed, 20 insertions, 0 deletions
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c index 61b14c9..0c2058a 100644 --- a/UefiCpuPkg/Library/MpInitLib/MpLib.c +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c @@ -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);
+ }
+ }
}
/**
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h index d13d5c0..685e96c 100644 --- a/UefiCpuPkg/Library/MpInitLib/MpLib.h +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h @@ -102,6 +102,9 @@ typedef struct { UINTN Dr3;
UINTN Dr6;
UINTN Dr7;
+ IA32_DESCRIPTOR Gdtr;
+ IA32_DESCRIPTOR Idtr;
+ UINT16 Tr;
} CPU_VOLATILE_REGISTERS;
//
|