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UefiCpuPkg/DxeMpLib: Allocate new safe stack < 4GB

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For long mode DXE, we will disable paging on AP to protected mode to execute AP
safe loop code in reserved memory range under 4GB. But we forget to allocate
stack for AP under 4GB and AP still are using original AP stack. If original AP
stack is larger than 4GB, it cannot be used after AP is transferred to protected
mode. Besides MwaitSupport == TRUE, AP stack is still required during phase of
disabling paging in long mode DXE.

Moreover, even though AP stack is always under 4GB (a) in Ia32 DXE and (b) with
this patch, after transferring to protected mode from X64 DXE, AP stack
(in BootServiceData) maybe crashed by OS after Exit Boot Service event.

This fix is to allocate reserved memory range under 4GB together with AP safe
loop code. APs will switch to new stack in safe loop code.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Jeff Fan
2016-11-23 21:52:24 +08:00
parent 081f6416ff
commit bf2786dc79
4 changed files with 31 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
View File

@@ -18,6 +18,7 @@
#include <Library/UefiBootServicesTableLib.h>
#define AP_CHECK_INTERVAL (EFI_TIMER_PERIOD_MILLISECONDS (100))
#define AP_SAFE_STACK_SIZE 128
CPU_MP_DATA *mCpuMpData = NULL;
EFI_EVENT mCheckAllApsEvent = NULL;
@@ -25,6 +26,7 @@ EFI_EVENT mMpInitExitBootServicesEvent = NULL;
EFI_EVENT mLegacyBootEvent = NULL;
volatile BOOLEAN mStopCheckAllApsStatus = TRUE;
VOID *mReservedApLoopFunc = NULL;
UINTN mReservedTopOfApStack;
/**
Get the pointer to CPU MP Data structure.
@@ -241,11 +243,18 @@ RelocateApLoop (
CPU_MP_DATA *CpuMpData;
BOOLEAN MwaitSupport;
ASM_RELOCATE_AP_LOOP AsmRelocateApLoopFunc;
UINTN ProcessorNumber;
MpInitLibWhoAmI (&ProcessorNumber);
CpuMpData = GetCpuMpData ();
MwaitSupport = IsMwaitSupport ();
AsmRelocateApLoopFunc = (ASM_RELOCATE_AP_LOOP) (UINTN) mReservedApLoopFunc;
AsmRelocateApLoopFunc (MwaitSupport, CpuMpData->ApTargetCState, CpuMpData->PmCodeSegment);
AsmRelocateApLoopFunc (
MwaitSupport,
CpuMpData->ApTargetCState,
CpuMpData->PmCodeSegment,
mReservedTopOfApStack - ProcessorNumber * AP_SAFE_STACK_SIZE
);
//
// It should never reach here
//
@@ -289,6 +298,7 @@ InitMpGlobalData (
{
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS Address;
UINTN ApSafeBufferSize;
SaveCpuMpData (CpuMpData);
@@ -307,16 +317,21 @@ InitMpGlobalData (
// Allocating it in advance since memory services are not available in
// Exit Boot Services callback function.
//
ApSafeBufferSize = CpuMpData->AddressMap.RelocateApLoopFuncSize;
ApSafeBufferSize += CpuMpData->CpuCount * AP_SAFE_STACK_SIZE;
Address = BASE_4GB - 1;
Status = gBS->AllocatePages (
AllocateMaxAddress,
EfiReservedMemoryType,
EFI_SIZE_TO_PAGES (sizeof (CpuMpData->AddressMap.RelocateApLoopFuncSize)),
EFI_SIZE_TO_PAGES (ApSafeBufferSize),
&Address
);
ASSERT_EFI_ERROR (Status);
mReservedApLoopFunc = (VOID *) (UINTN) Address;
ASSERT (mReservedApLoopFunc != NULL);
mReservedTopOfApStack = (UINTN) Address + EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (ApSafeBufferSize));
ASSERT ((mReservedTopOfApStack & (UINTN)(CPU_STACK_ALIGNMENT - 1)) == 0);
CopyMem (
mReservedApLoopFunc,
CpuMpData->AddressMap.RelocateApLoopFuncAddress,