/** @file | |
CPU Exception Library provides PEI/DXE/SMM CPU common exception handler. | |
Copyright (c) 2012 - 2022, Intel Corporation. All rights reserved.<BR> | |
SPDX-License-Identifier: BSD-2-Clause-Patent | |
**/ | |
#include <Library/DebugLib.h> | |
#include <Library/CcExitLib.h> | |
#include "CpuExceptionCommon.h" | |
/** | |
Internal worker function for common exception handler. | |
@param ExceptionType Exception type. | |
@param SystemContext Pointer to EFI_SYSTEM_CONTEXT. | |
@param ExceptionHandlerData Pointer to exception handler data. | |
**/ | |
VOID | |
CommonExceptionHandlerWorker ( | |
IN EFI_EXCEPTION_TYPE ExceptionType, | |
IN EFI_SYSTEM_CONTEXT SystemContext, | |
IN EXCEPTION_HANDLER_DATA *ExceptionHandlerData | |
) | |
{ | |
EFI_STATUS Status; | |
EXCEPTION_HANDLER_CONTEXT *ExceptionHandlerContext; | |
RESERVED_VECTORS_DATA *ReservedVectors; | |
EFI_CPU_INTERRUPT_HANDLER *ExternalInterruptHandler; | |
switch (ExceptionType) { | |
case VC_EXCEPTION: | |
// | |
// #VC needs to be handled immediately upon enabling exception handling | |
// and therefore can't use the RegisterCpuInterruptHandler() interface. | |
// | |
// Handle the #VC: | |
// On EFI_SUCCESS - Exception has been handled, return | |
// On other - ExceptionType contains (possibly new) exception | |
// value | |
// | |
Status = CcExitHandleVc (&ExceptionType, SystemContext); | |
if (!EFI_ERROR (Status)) { | |
return; | |
} | |
break; | |
case VE_EXCEPTION: | |
// | |
// #VE needs to be handled immediately upon enabling exception handling | |
// and therefore can't use the RegisterCpuInterruptHandler() interface. | |
// | |
// Handle the #VE: | |
// On EFI_SUCCESS - Exception has been handled, return | |
// On other - ExceptionType contains (possibly new) exception | |
// value | |
// | |
Status = CcExitHandleVe (&ExceptionType, SystemContext); | |
if (!EFI_ERROR (Status)) { | |
return; | |
} | |
break; | |
default: | |
break; | |
} | |
ExceptionHandlerContext = (EXCEPTION_HANDLER_CONTEXT *)(UINTN)(SystemContext.SystemContextIa32); | |
ReservedVectors = ExceptionHandlerData->ReservedVectors; | |
ExternalInterruptHandler = ExceptionHandlerData->ExternalInterruptHandler; | |
switch (ReservedVectors[ExceptionType].Attribute) { | |
case EFI_VECTOR_HANDOFF_HOOK_BEFORE: | |
// | |
// The new exception handler registered by RegisterCpuInterruptHandler() is executed BEFORE original handler. | |
// Save the original handler to stack so the assembly code can jump to it instead of returning from handler. | |
// | |
ExceptionHandlerContext->ExceptionDataFlag = (mErrorCodeFlag & (1 << ExceptionType)) ? TRUE : FALSE; | |
ExceptionHandlerContext->OldIdtHandler = ReservedVectors[ExceptionType].ExceptonHandler; | |
break; | |
case EFI_VECTOR_HANDOFF_HOOK_AFTER: | |
while (TRUE) { | |
// | |
// If spin-lock can be acquired, it's the first time entering here. | |
// | |
if (AcquireSpinLockOrFail (&ReservedVectors[ExceptionType].SpinLock)) { | |
// | |
// The new exception handler registered by RegisterCpuInterruptHandler() is executed AFTER original handler. | |
// Save the original handler to stack but skip running the new handler so the original handler is executed | |
// firstly. | |
// | |
ReservedVectors[ExceptionType].ApicId = GetApicId (); | |
ArchSaveExceptionContext (ExceptionType, SystemContext, ExceptionHandlerData); | |
ExceptionHandlerContext->ExceptionDataFlag = (mErrorCodeFlag & (1 << ExceptionType)) ? TRUE : FALSE; | |
ExceptionHandlerContext->OldIdtHandler = ReservedVectors[ExceptionType].ExceptonHandler; | |
return; | |
} | |
// | |
// If spin-lock cannot be acquired, it's the second time entering here. | |
// 'break' instead of 'return' is used so the new exception handler can be executed. | |
// | |
if (ReservedVectors[ExceptionType].ApicId == GetApicId ()) { | |
// | |
// Old IDT handler has been executed, then restore CPU exception content to | |
// run new exception handler. | |
// | |
ArchRestoreExceptionContext (ExceptionType, SystemContext, ExceptionHandlerData); | |
// | |
// Release spin lock for ApicId | |
// | |
ReleaseSpinLock (&ReservedVectors[ExceptionType].SpinLock); | |
break; | |
} | |
CpuPause (); | |
} | |
break; | |
case 0xffffffff: | |
break; | |
default: | |
// | |
// It should never reach here | |
// | |
CpuDeadLoop (); | |
break; | |
} | |
if ((ExternalInterruptHandler != NULL) && | |
(ExternalInterruptHandler[ExceptionType] != NULL)) | |
{ | |
(ExternalInterruptHandler[ExceptionType])(ExceptionType, SystemContext); | |
} else if (ExceptionType < CPU_EXCEPTION_NUM) { | |
// | |
// Get Spinlock to display CPU information | |
// | |
while (!AcquireSpinLockOrFail (&ExceptionHandlerData->DisplayMessageSpinLock)) { | |
CpuPause (); | |
} | |
// | |
// Initialize the serial port before dumping. | |
// | |
SerialPortInitialize (); | |
// | |
// Display ExceptionType, CPU information and Image information | |
// | |
DumpImageAndCpuContent (ExceptionType, SystemContext); | |
// | |
// Release Spinlock of output message | |
// | |
ReleaseSpinLock (&ExceptionHandlerData->DisplayMessageSpinLock); | |
// | |
// Enter a dead loop if needn't to execute old IDT handler further | |
// | |
if (ReservedVectors[ExceptionType].Attribute != EFI_VECTOR_HANDOFF_HOOK_BEFORE) { | |
CpuDeadLoop (); | |
} | |
} | |
} | |
/** | |
Internal worker function to update IDT entries accordling to vector attributes. | |
@param[in] IdtTable Pointer to IDT table. | |
@param[in] TemplateMap Pointer to a buffer where the address map is | |
returned. | |
@param[in] ExceptionHandlerData Pointer to exception handler data. | |
**/ | |
VOID | |
UpdateIdtTable ( | |
IN IA32_IDT_GATE_DESCRIPTOR *IdtTable, | |
IN EXCEPTION_HANDLER_TEMPLATE_MAP *TemplateMap, | |
IN EXCEPTION_HANDLER_DATA *ExceptionHandlerData | |
) | |
{ | |
UINT16 CodeSegment; | |
UINTN Index; | |
UINTN InterruptHandler; | |
RESERVED_VECTORS_DATA *ReservedVectors; | |
ReservedVectors = ExceptionHandlerData->ReservedVectors; | |
// | |
// Use current CS as the segment selector of interrupt gate in IDT | |
// | |
CodeSegment = AsmReadCs (); | |
for (Index = 0; Index < ExceptionHandlerData->IdtEntryCount; Index++) { | |
IdtTable[Index].Bits.Selector = CodeSegment; | |
// | |
// Check reserved vectors attributes | |
// | |
switch (ReservedVectors[Index].Attribute) { | |
case EFI_VECTOR_HANDOFF_DO_NOT_HOOK: | |
// | |
// Keep original IDT entry | |
// | |
continue; | |
case EFI_VECTOR_HANDOFF_HOOK_AFTER: | |
InitializeSpinLock (&ReservedVectors[Index].SpinLock); | |
CopyMem ( | |
(VOID *)ReservedVectors[Index].HookAfterStubHeaderCode, | |
(VOID *)TemplateMap->HookAfterStubHeaderStart, | |
TemplateMap->ExceptionStubHeaderSize | |
); | |
AsmVectorNumFixup ( | |
(VOID *)ReservedVectors[Index].HookAfterStubHeaderCode, | |
(UINT8)Index, | |
(VOID *)TemplateMap->HookAfterStubHeaderStart | |
); | |
// | |
// Go on the following code | |
// | |
case EFI_VECTOR_HANDOFF_HOOK_BEFORE: | |
// | |
// Save original IDT handler address | |
// | |
ReservedVectors[Index].ExceptonHandler = ArchGetIdtHandler (&IdtTable[Index]); | |
// | |
// Go on the following code | |
// | |
default: | |
// | |
// Update new IDT entry | |
// | |
InterruptHandler = TemplateMap->ExceptionStart + Index * TemplateMap->ExceptionStubHeaderSize; | |
ArchUpdateIdtEntry (&IdtTable[Index], InterruptHandler); | |
break; | |
} | |
} | |
} | |
/** | |
Internal worker function to initialize exception handler. | |
@param[in] VectorInfo Pointer to reserved vector list. | |
@param[in, out] ExceptionHandlerData Pointer to exception handler data. | |
@retval EFI_SUCCESS CPU Exception Entries have been successfully initialized | |
with default exception handlers. | |
@retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL. | |
@retval EFI_UNSUPPORTED This function is not supported. | |
**/ | |
EFI_STATUS | |
InitializeCpuExceptionHandlersWorker ( | |
IN EFI_VECTOR_HANDOFF_INFO *VectorInfo OPTIONAL, | |
IN OUT EXCEPTION_HANDLER_DATA *ExceptionHandlerData | |
) | |
{ | |
EFI_STATUS Status; | |
IA32_DESCRIPTOR IdtDescriptor; | |
UINTN IdtEntryCount; | |
EXCEPTION_HANDLER_TEMPLATE_MAP TemplateMap; | |
IA32_IDT_GATE_DESCRIPTOR *IdtTable; | |
RESERVED_VECTORS_DATA *ReservedVectors; | |
ReservedVectors = ExceptionHandlerData->ReservedVectors; | |
SetMem ((VOID *)ReservedVectors, sizeof (RESERVED_VECTORS_DATA) * ExceptionHandlerData->IdtEntryCount, 0xff); | |
if (VectorInfo != NULL) { | |
Status = ReadAndVerifyVectorInfo (VectorInfo, ReservedVectors, ExceptionHandlerData->IdtEntryCount); | |
if (EFI_ERROR (Status)) { | |
return EFI_INVALID_PARAMETER; | |
} | |
} | |
// | |
// Setup the exception handlers according to IDT size, but no more than | |
// ExceptionHandlerData->IdtEntryCount (32 in PEI and SMM, 256 in DXE) handlers. | |
// | |
AsmReadIdtr (&IdtDescriptor); | |
IdtEntryCount = (IdtDescriptor.Limit + 1) / sizeof (IA32_IDT_GATE_DESCRIPTOR); | |
ExceptionHandlerData->IdtEntryCount = MIN (IdtEntryCount, ExceptionHandlerData->IdtEntryCount); | |
IdtTable = (IA32_IDT_GATE_DESCRIPTOR *)IdtDescriptor.Base; | |
AsmGetTemplateAddressMap (&TemplateMap); | |
ASSERT (TemplateMap.ExceptionStubHeaderSize <= HOOKAFTER_STUB_SIZE); | |
UpdateIdtTable (IdtTable, &TemplateMap, ExceptionHandlerData); | |
return EFI_SUCCESS; | |
} | |
/** | |
Registers a function to be called from the processor interrupt handler. | |
@param[in] InterruptType Defines which interrupt or exception to hook. | |
@param[in] InterruptHandler A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called | |
when a processor interrupt occurs. If this parameter is NULL, then the handler | |
will be uninstalled | |
@param[in] ExceptionHandlerData Pointer to exception handler data. | |
@retval EFI_SUCCESS The handler for the processor interrupt was successfully installed or uninstalled. | |
@retval EFI_ALREADY_STARTED InterruptHandler is not NULL, and a handler for InterruptType was | |
previously installed. | |
@retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not | |
previously installed. | |
@retval EFI_UNSUPPORTED The interrupt specified by InterruptType is not supported, | |
or this function is not supported. | |
**/ | |
EFI_STATUS | |
RegisterCpuInterruptHandlerWorker ( | |
IN EFI_EXCEPTION_TYPE InterruptType, | |
IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler, | |
IN EXCEPTION_HANDLER_DATA *ExceptionHandlerData | |
) | |
{ | |
UINTN EnabledInterruptNum; | |
RESERVED_VECTORS_DATA *ReservedVectors; | |
EFI_CPU_INTERRUPT_HANDLER *ExternalInterruptHandler; | |
EnabledInterruptNum = ExceptionHandlerData->IdtEntryCount; | |
ReservedVectors = ExceptionHandlerData->ReservedVectors; | |
ExternalInterruptHandler = ExceptionHandlerData->ExternalInterruptHandler; | |
if ((InterruptType < 0) || (InterruptType >= (EFI_EXCEPTION_TYPE)EnabledInterruptNum) || | |
(ReservedVectors[InterruptType].Attribute == EFI_VECTOR_HANDOFF_DO_NOT_HOOK)) | |
{ | |
return EFI_UNSUPPORTED; | |
} | |
if ((InterruptHandler == NULL) && (ExternalInterruptHandler[InterruptType] == NULL)) { | |
return EFI_INVALID_PARAMETER; | |
} | |
if ((InterruptHandler != NULL) && (ExternalInterruptHandler[InterruptType] != NULL)) { | |
return EFI_ALREADY_STARTED; | |
} | |
ExternalInterruptHandler[InterruptType] = InterruptHandler; | |
return EFI_SUCCESS; | |
} |