historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/roms/edk2/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c
2024-01-16 11:20:27 -06:00

204 lines
6.6 KiB
C

/** @file
SMM CPU misc functions for Ia32 arch specific.
Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "PiSmmCpuDxeSmm.h"
extern UINT64 gTaskGateDescriptor;
EFI_PHYSICAL_ADDRESS mGdtBuffer;
UINTN mGdtBufferSize;
extern BOOLEAN mCetSupported;
extern UINTN mSmmShadowStackSize;
X86_ASSEMBLY_PATCH_LABEL mPatchCetPl0Ssp;
X86_ASSEMBLY_PATCH_LABEL mPatchCetInterruptSsp;
UINT32 mCetPl0Ssp;
UINT32 mCetInterruptSsp;
/**
Initialize IDT for SMM Stack Guard.
**/
VOID
EFIAPI
InitializeIDTSmmStackGuard (
VOID
)
{
IA32_IDT_GATE_DESCRIPTOR *IdtGate;
//
// If SMM Stack Guard feature is enabled, the Page Fault Exception entry in IDT
// is a Task Gate Descriptor so that when a Page Fault Exception occurs,
// the processors can use a known good stack in case stack is ran out.
//
IdtGate = (IA32_IDT_GATE_DESCRIPTOR *)gcSmiIdtr.Base;
IdtGate += EXCEPT_IA32_PAGE_FAULT;
IdtGate->Uint64 = gTaskGateDescriptor;
}
/**
Initialize Gdt for all processors.
@param[in] Cr3 CR3 value.
@param[out] GdtStepSize The step size for GDT table.
@return GdtBase for processor 0.
GdtBase for processor X is: GdtBase + (GdtStepSize * X)
**/
VOID *
InitGdt (
IN UINTN Cr3,
OUT UINTN *GdtStepSize
)
{
UINTN Index;
IA32_SEGMENT_DESCRIPTOR *GdtDescriptor;
UINTN TssBase;
UINTN GdtTssTableSize;
UINT8 *GdtTssTables;
UINTN GdtTableStepSize;
UINTN InterruptShadowStack;
if (FeaturePcdGet (PcdCpuSmmStackGuard)) {
//
// For IA32 SMM, if SMM Stack Guard feature is enabled, we use 2 TSS.
// in this case, we allocate separate GDT/TSS for each CPUs to avoid TSS load contention
// on each SMI entry.
//
//
// Enlarge GDT to contain 2 TSS descriptors
//
gcSmiGdtr.Limit += (UINT16)(2 * sizeof (IA32_SEGMENT_DESCRIPTOR));
GdtTssTableSize = (gcSmiGdtr.Limit + 1 + TSS_SIZE + EXCEPTION_TSS_SIZE + 7) & ~7; // 8 bytes aligned
mGdtBufferSize = GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus;
//
// IA32 Stack Guard need use task switch to switch stack that need
// write GDT and TSS, so AllocateCodePages() could not be used here
// as code pages will be set to RO.
//
GdtTssTables = (UINT8*)AllocatePages (EFI_SIZE_TO_PAGES (mGdtBufferSize));
ASSERT (GdtTssTables != NULL);
mGdtBuffer = (UINTN)GdtTssTables;
GdtTableStepSize = GdtTssTableSize;
for (Index = 0; Index < gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; Index++) {
CopyMem (GdtTssTables + GdtTableStepSize * Index, (VOID*)(UINTN)gcSmiGdtr.Base, gcSmiGdtr.Limit + 1 + TSS_SIZE + EXCEPTION_TSS_SIZE);
//
// Fixup TSS descriptors
//
TssBase = (UINTN)(GdtTssTables + GdtTableStepSize * Index + gcSmiGdtr.Limit + 1);
GdtDescriptor = (IA32_SEGMENT_DESCRIPTOR *)(TssBase) - 2;
GdtDescriptor->Bits.BaseLow = (UINT16)TssBase;
GdtDescriptor->Bits.BaseMid = (UINT8)(TssBase >> 16);
GdtDescriptor->Bits.BaseHigh = (UINT8)(TssBase >> 24);
TssBase += TSS_SIZE;
GdtDescriptor++;
GdtDescriptor->Bits.BaseLow = (UINT16)TssBase;
GdtDescriptor->Bits.BaseMid = (UINT8)(TssBase >> 16);
GdtDescriptor->Bits.BaseHigh = (UINT8)(TssBase >> 24);
//
// Fixup TSS segments
//
// ESP as known good stack
//
*(UINTN *)(TssBase + TSS_IA32_ESP_OFFSET) = mSmmStackArrayBase + EFI_PAGE_SIZE + Index * mSmmStackSize;
*(UINT32 *)(TssBase + TSS_IA32_CR3_OFFSET) = Cr3;
//
// Setup ShadowStack for stack switch
//
if ((PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) && mCetSupported) {
InterruptShadowStack = (UINTN)(mSmmStackArrayBase + mSmmStackSize + EFI_PAGES_TO_SIZE (1) - sizeof(UINT64) + (mSmmStackSize + mSmmShadowStackSize) * Index);
*(UINT32 *)(TssBase + TSS_IA32_SSP_OFFSET) = (UINT32)InterruptShadowStack;
}
}
} else {
//
// Just use original table, AllocatePage and copy them here to make sure GDTs are covered in page memory.
//
GdtTssTableSize = gcSmiGdtr.Limit + 1;
mGdtBufferSize = GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus;
GdtTssTables = (UINT8*)AllocateCodePages (EFI_SIZE_TO_PAGES (mGdtBufferSize));
ASSERT (GdtTssTables != NULL);
mGdtBuffer = (UINTN)GdtTssTables;
GdtTableStepSize = GdtTssTableSize;
for (Index = 0; Index < gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; Index++) {
CopyMem (GdtTssTables + GdtTableStepSize * Index, (VOID*)(UINTN)gcSmiGdtr.Base, gcSmiGdtr.Limit + 1);
}
}
*GdtStepSize = GdtTableStepSize;
return GdtTssTables;
}
/**
Transfer AP to safe hlt-loop after it finished restore CPU features on S3 patch.
@param[in] ApHltLoopCode The address of the safe hlt-loop function.
@param[in] TopOfStack A pointer to the new stack to use for the ApHltLoopCode.
@param[in] NumberToFinishAddress Address of Semaphore of APs finish count.
**/
VOID
TransferApToSafeState (
IN UINTN ApHltLoopCode,
IN UINTN TopOfStack,
IN UINTN NumberToFinishAddress
)
{
SwitchStack (
(SWITCH_STACK_ENTRY_POINT)ApHltLoopCode,
(VOID *)NumberToFinishAddress,
NULL,
(VOID *)TopOfStack
);
//
// It should never reach here
//
ASSERT (FALSE);
}
/**
Initialize the shadow stack related data structure.
@param CpuIndex The index of CPU.
@param ShadowStack The bottom of the shadow stack for this CPU.
**/
VOID
InitShadowStack (
IN UINTN CpuIndex,
IN VOID *ShadowStack
)
{
UINTN SmmShadowStackSize;
if ((PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) && mCetSupported) {
SmmShadowStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmShadowStackSize)));
if (FeaturePcdGet (PcdCpuSmmStackGuard)) {
SmmShadowStackSize += EFI_PAGES_TO_SIZE (2);
}
mCetPl0Ssp = (UINT32)((UINTN)ShadowStack + SmmShadowStackSize - sizeof(UINT64));
PatchInstructionX86 (mPatchCetPl0Ssp, mCetPl0Ssp, 4);
DEBUG ((DEBUG_INFO, "mCetPl0Ssp - 0x%x\n", mCetPl0Ssp));
DEBUG ((DEBUG_INFO, "ShadowStack - 0x%x\n", ShadowStack));
DEBUG ((DEBUG_INFO, " SmmShadowStackSize - 0x%x\n", SmmShadowStackSize));
if (FeaturePcdGet (PcdCpuSmmStackGuard)) {
mCetInterruptSsp = (UINT32)((UINTN)ShadowStack + EFI_PAGES_TO_SIZE(1) - sizeof(UINT64));
PatchInstructionX86 (mPatchCetInterruptSsp, mCetInterruptSsp, 4);
DEBUG ((DEBUG_INFO, "mCetInterruptSsp - 0x%x\n", mCetInterruptSsp));
}
}
}