UefiCpuPkg/MpInitLib: For SEV-ES guest, set stack based on processor number

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3008

Set the SEV-ES reset stack address for an AP based on the processor number
instead of the APIC ID in case the APIC IDs are not zero-based and densely
packed/enumerated. This will ensure an AP reset stack address does not get
set outside of the AP reset stack memory allocation.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Acked-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <24866de07d2a954dec71df70972f1851273020d8.1604685192.git.thomas.lendacky@amd.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 1f47ff3f73..681fa79b4c 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -680,11 +680,16 @@ MpInitLibSevEsAPReset (
   IN CPU_MP_DATA                  *CpuMpData

   )

 {

+  EFI_STATUS       Status;

+  UINTN            ProcessorNumber;

   UINT16           Code16, Code32;

   AP_RESET         *APResetFn;

   UINTN            BufferStart;

   UINTN            StackStart;

 

+  Status = GetProcessorNumber (CpuMpData, &ProcessorNumber);

+  ASSERT_EFI_ERROR (Status);

+

   Code16 = GetProtectedMode16CS ();

   Code32 = GetProtectedMode32CS ();

 

@@ -696,7 +701,7 @@ MpInitLibSevEsAPReset (
 

   BufferStart = CpuMpData->MpCpuExchangeInfo->BufferStart;

   StackStart = CpuMpData->SevEsAPResetStackStart -

-                 (AP_RESET_STACK_SIZE * GetApicId ());

+                 (AP_RESET_STACK_SIZE * ProcessorNumber);

 

   //

   // This call never returns.