diff options
Diffstat (limited to 'UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c')
| -rw-r--r-- | UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c index f2c39eb193..6ac8549839 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ArchExceptionHandler.c @@ -108,6 +108,194 @@ ArchRestoreExceptionContext ( }
/**
+ Setup separate stack for given exceptions.
+
+ @param[in] StackSwitchData Pointer to data required for setuping up
+ stack switch.
+
+ @retval EFI_SUCCESS The exceptions have been successfully
+ initialized with new stack.
+ @retval EFI_INVALID_PARAMETER StackSwitchData contains invalid content.
+
+**/
+EFI_STATUS
+ArchSetupExcpetionStack (
+ IN CPU_EXCEPTION_INIT_DATA *StackSwitchData
+ )
+{
+ IA32_DESCRIPTOR Gdtr;
+ IA32_DESCRIPTOR Idtr;
+ IA32_IDT_GATE_DESCRIPTOR *IdtTable;
+ IA32_TSS_DESCRIPTOR *TssDesc;
+ IA32_TASK_STATE_SEGMENT *Tss;
+ UINTN StackTop;
+ UINTN Index;
+ UINTN Vector;
+ UINTN TssBase;
+ UINTN GdtSize;
+ EXCEPTION_HANDLER_TEMPLATE_MAP TemplateMap;
+
+ if (StackSwitchData == NULL ||
+ StackSwitchData->Ia32.Revision != CPU_EXCEPTION_INIT_DATA_REV ||
+ StackSwitchData->Ia32.KnownGoodStackTop == 0 ||
+ StackSwitchData->Ia32.KnownGoodStackSize == 0 ||
+ StackSwitchData->Ia32.StackSwitchExceptions == NULL ||
+ StackSwitchData->Ia32.StackSwitchExceptionNumber == 0 ||
+ StackSwitchData->Ia32.StackSwitchExceptionNumber > CPU_EXCEPTION_NUM ||
+ StackSwitchData->Ia32.GdtTable == NULL ||
+ StackSwitchData->Ia32.IdtTable == NULL ||
+ StackSwitchData->Ia32.ExceptionTssDesc == NULL ||
+ StackSwitchData->Ia32.ExceptionTss == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // The caller is responsible for that the GDT table, no matter the existing
+ // one or newly allocated, has enough space to hold descriptors for exception
+ // task-state segments.
+ //
+ if (((UINTN)StackSwitchData->Ia32.GdtTable & (IA32_GDT_ALIGNMENT - 1)) != 0) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if ((UINTN)StackSwitchData->Ia32.ExceptionTssDesc < (UINTN)(StackSwitchData->Ia32.GdtTable)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if ((UINTN)StackSwitchData->Ia32.ExceptionTssDesc + StackSwitchData->Ia32.ExceptionTssDescSize >
+ ((UINTN)(StackSwitchData->Ia32.GdtTable) + StackSwitchData->Ia32.GdtTableSize)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // We need one descriptor and one TSS for current task and every exception
+ // specified.
+ //
+ if (StackSwitchData->Ia32.ExceptionTssDescSize <
+ sizeof (IA32_TSS_DESCRIPTOR) * (StackSwitchData->Ia32.StackSwitchExceptionNumber + 1)) {
+ return EFI_INVALID_PARAMETER;
+ }
+ if (StackSwitchData->Ia32.ExceptionTssSize <
+ sizeof (IA32_TASK_STATE_SEGMENT) * (StackSwitchData->Ia32.StackSwitchExceptionNumber + 1)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ TssDesc = StackSwitchData->Ia32.ExceptionTssDesc;
+ Tss = StackSwitchData->Ia32.ExceptionTss;
+
+ //
+ // Initialize new GDT table and/or IDT table, if any
+ //
+ AsmReadIdtr (&Idtr);
+ AsmReadGdtr (&Gdtr);
+
+ GdtSize = (UINTN)TssDesc +
+ sizeof (IA32_TSS_DESCRIPTOR) *
+ (StackSwitchData->Ia32.StackSwitchExceptionNumber + 1) -
+ (UINTN)(StackSwitchData->Ia32.GdtTable);
+ if ((UINTN)StackSwitchData->Ia32.GdtTable != Gdtr.Base) {
+ CopyMem (StackSwitchData->Ia32.GdtTable, (VOID *)Gdtr.Base, Gdtr.Limit + 1);
+ Gdtr.Base = (UINTN)StackSwitchData->Ia32.GdtTable;
+ Gdtr.Limit = (UINT16)GdtSize - 1;
+ }
+
+ if ((UINTN)StackSwitchData->Ia32.IdtTable != Idtr.Base) {
+ Idtr.Base = (UINTN)StackSwitchData->Ia32.IdtTable;
+ }
+ if (StackSwitchData->Ia32.IdtTableSize > 0) {
+ Idtr.Limit = (UINT16)(StackSwitchData->Ia32.IdtTableSize - 1);
+ }
+
+ //
+ // Fixup current task descriptor. Task-state segment for current task will
+ // be filled by processor during task switching.
+ //
+ TssBase = (UINTN)Tss;
+
+ TssDesc->Bits.LimitLow = sizeof(IA32_TASK_STATE_SEGMENT) - 1;
+ TssDesc->Bits.BaseLow = (UINT16)TssBase;
+ TssDesc->Bits.BaseMid = (UINT8)(TssBase >> 16);
+ TssDesc->Bits.Type = IA32_GDT_TYPE_TSS;
+ TssDesc->Bits.P = 1;
+ TssDesc->Bits.LimitHigh = 0;
+ TssDesc->Bits.BaseHigh = (UINT8)(TssBase >> 24);
+
+ //
+ // Fixup exception task descriptor and task-state segment
+ //
+ AsmGetTssTemplateMap (&TemplateMap);
+ StackTop = StackSwitchData->Ia32.KnownGoodStackTop - CPU_STACK_ALIGNMENT;
+ StackTop = (UINTN)ALIGN_POINTER (StackTop, CPU_STACK_ALIGNMENT);
+ IdtTable = StackSwitchData->Ia32.IdtTable;
+ for (Index = 0; Index < StackSwitchData->Ia32.StackSwitchExceptionNumber; ++Index) {
+ TssDesc += 1;
+ Tss += 1;
+
+ //
+ // Fixup TSS descriptor
+ //
+ TssBase = (UINTN)Tss;
+
+ TssDesc->Bits.LimitLow = sizeof(IA32_TASK_STATE_SEGMENT) - 1;
+ TssDesc->Bits.BaseLow = (UINT16)TssBase;
+ TssDesc->Bits.BaseMid = (UINT8)(TssBase >> 16);
+ TssDesc->Bits.Type = IA32_GDT_TYPE_TSS;
+ TssDesc->Bits.P = 1;
+ TssDesc->Bits.LimitHigh = 0;
+ TssDesc->Bits.BaseHigh = (UINT8)(TssBase >> 24);
+
+ //
+ // Fixup TSS
+ //
+ Vector = StackSwitchData->Ia32.StackSwitchExceptions[Index];
+ if (Vector >= CPU_EXCEPTION_NUM ||
+ Vector >= (Idtr.Limit + 1) / sizeof (IA32_IDT_GATE_DESCRIPTOR)) {
+ continue;
+ }
+
+ Tss->EIP = (UINT32)(TemplateMap.ExceptionStart
+ + Vector * TemplateMap.ExceptionStubHeaderSize);
+ Tss->EFLAGS = 0x2;
+ Tss->ESP = StackTop;
+ Tss->CR3 = AsmReadCr3 ();
+ Tss->ES = AsmReadEs ();
+ Tss->CS = AsmReadCs ();
+ Tss->SS = AsmReadSs ();
+ Tss->DS = AsmReadDs ();
+ Tss->FS = AsmReadFs ();
+ Tss->GS = AsmReadGs ();
+
+ StackTop -= StackSwitchData->Ia32.KnownGoodStackSize;
+
+ //
+ // Update IDT to use Task Gate for given exception
+ //
+ IdtTable[Vector].Bits.OffsetLow = 0;
+ IdtTable[Vector].Bits.Selector = (UINT16)((UINTN)TssDesc - Gdtr.Base);
+ IdtTable[Vector].Bits.Reserved_0 = 0;
+ IdtTable[Vector].Bits.GateType = IA32_IDT_GATE_TYPE_TASK;
+ IdtTable[Vector].Bits.OffsetHigh = 0;
+ }
+
+ //
+ // Publish GDT
+ //
+ AsmWriteGdtr (&Gdtr);
+
+ //
+ // Load current task
+ //
+ AsmWriteTr ((UINT16)((UINTN)StackSwitchData->Ia32.ExceptionTssDesc - Gdtr.Base));
+
+ //
+ // Publish IDT
+ //
+ AsmWriteIdtr (&Idtr);
+
+ return EFI_SUCCESS;
+}
+
+/**
Display processor context.
@param[in] ExceptionType Exception type.
|