commit e09b6b5953db38db87b84c80a2e95a82a1c91020
author Jian J Wang <jian.j.wang@intel.com> Mon Sep 03 10:47:54 2018 +0800
committer Jian J Wang <jian.j.wang@intel.com> Mon Sep 10 09:28:27 2018 +0800
tree 62cac89b1d5da9661dddb41dcc6d73ce5972eaec
parent fc0e7fd5e8aad193fcc3479634d5c69996f6460a

UefiCpuPkg/MpInitLib: fix register restore issue in AP wakeup

The conflict issues are introduced by Stack Guard feature enabled for
PEI.

The first is CR0 which should be restored after CR3 and CR4.
Another is TR which should not be passed from BSP to AP during init
phase.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: "Ware, Ryan R" <ryan.r.ware@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>

UefiCpuPkg/Library/MpInitLib/MpLib.c

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 5c562d4..85ca4a2 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -217,9 +217,9 @@
   CPUID_VERSION_INFO_EDX        VersionInfoEdx;

   IA32_TSS_DESCRIPTOR           *Tss;

 

-  AsmWriteCr0 (VolatileRegisters->Cr0);

   AsmWriteCr3 (VolatileRegisters->Cr3);

   AsmWriteCr4 (VolatileRegisters->Cr4);

+  AsmWriteCr0 (VolatileRegisters->Cr0);

 

   if (IsRestoreDr) {

     AsmCpuid (CPUID_VERSION_INFO, NULL, NULL, NULL, &VersionInfoEdx.Uint32);

@@ -1558,7 +1558,7 @@
   ApLoopMode  = GetApLoopMode (&MonitorFilterSize);

 

   //

-  // Save BSP's Control registers for APs

+  // Save BSP's Control registers for APs.

   //

   SaveVolatileRegisters (&VolatileRegisters);

 

@@ -1656,6 +1656,10 @@
   //

   CopyMem ((VOID *)ApIdtBase, (VOID *)VolatileRegisters.Idtr.Base, VolatileRegisters.Idtr.Limit + 1);

   VolatileRegisters.Idtr.Base = ApIdtBase;

+  //

+  // Don't pass BSP's TR to APs to avoid AP init failure.

+  //

+  VolatileRegisters.Tr = 0;

   CopyMem (&CpuMpData->CpuData[0].VolatileRegisters, &VolatileRegisters, sizeof (VolatileRegisters));

   //

   // Set BSP basic information