sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

UefiCpuPkg: Simplify InitializeSeparateExceptionStacks

Browse Source 
Hide the Exception implementation details in CpuExcetionHandlerLib and
caller only need to provide buffer

Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>
This commit is contained in:
Liu, Zhiguang
2022-08-09 09:25:35 +08:00
committed by mergify[bot]
parent 1da2012d93
commit 0f7bccf584
11 changed files with 285 additions and 336 deletions
Download Patch File Download Diff File Expand all files Collapse all files

162
UefiCpuPkg/CpuDxe/CpuMp.c
View File

@@ -596,23 +596,13 @@ CollectBistDataFromHob (
}
}
/**
Get GDT register value.
This function is mainly for AP purpose because AP may have different GDT
table than BSP.
@param[in,out] Buffer The pointer to private data buffer.
**/
VOID
EFIAPI
GetGdtr (
IN OUT VOID *Buffer
)
{
AsmReadGdtr ((IA32_DESCRIPTOR *)Buffer);
}
//
// Structure for InitializeSeparateExceptionStacks
//
typedef struct {
VOID *Buffer;
UINTN *BufferSize;
} EXCEPTION_STACK_SWITCH_CONTEXT;
/**
Initializes CPU exceptions handlers for the sake of stack switch requirement.
@@ -629,27 +619,17 @@ InitializeExceptionStackSwitchHandlers (
IN OUT VOID *Buffer
)
{
CPU_EXCEPTION_INIT_DATA *EssData;
IA32_DESCRIPTOR Idtr;
EFI_STATUS Status;
EXCEPTION_STACK_SWITCH_CONTEXT *SwitchStackData;
EssData = Buffer;
//
// We don't plan to replace IDT table with a new one, but we should not assume
// the AP's IDT is the same as BSP's IDT either.
//
AsmReadIdtr (&Idtr);
EssData->Ia32.IdtTable = (VOID *)Idtr.Base;
EssData->Ia32.IdtTableSize = Idtr.Limit + 1;
Status = InitializeSeparateExceptionStacks (EssData);
ASSERT_EFI_ERROR (Status);
SwitchStackData = (EXCEPTION_STACK_SWITCH_CONTEXT *)Buffer;
InitializeSeparateExceptionStacks (SwitchStackData->Buffer, SwitchStackData->BufferSize);
}
/**
Initializes MP exceptions handlers for the sake of stack switch requirement.
This function will allocate required resources required to setup stack switch
and pass them through CPU_EXCEPTION_INIT_DATA to each logic processor.
and pass them through SwitchStackData to each logic processor.
**/
VOID
@@ -657,129 +637,53 @@ InitializeMpExceptionStackSwitchHandlers (
VOID
)
{
UINTN Index;
UINTN Bsp;
UINTN ExceptionNumber;
UINTN OldGdtSize;
UINTN NewGdtSize;
UINTN NewStackSize;
IA32_DESCRIPTOR Gdtr;
CPU_EXCEPTION_INIT_DATA EssData;
UINT8 *GdtBuffer;
UINT8 *StackTop;
UINTN Index;
UINTN Bsp;
EXCEPTION_STACK_SWITCH_CONTEXT SwitchStackData;
UINTN BufferSize;
ExceptionNumber = FixedPcdGetSize (PcdCpuStackSwitchExceptionList);
NewStackSize = FixedPcdGet32 (PcdCpuKnownGoodStackSize) * ExceptionNumber;
StackTop = AllocateRuntimeZeroPool (NewStackSize * mNumberOfProcessors);
ASSERT (StackTop != NULL);
StackTop += NewStackSize * mNumberOfProcessors;
//
// The default exception handlers must have been initialized. Let's just skip
// it in this method.
//
EssData.Ia32.Revision = CPU_EXCEPTION_INIT_DATA_REV;
EssData.Ia32.InitDefaultHandlers = FALSE;
EssData.Ia32.StackSwitchExceptions = FixedPcdGetPtr (PcdCpuStackSwitchExceptionList);
EssData.Ia32.StackSwitchExceptionNumber = ExceptionNumber;
EssData.Ia32.KnownGoodStackSize = FixedPcdGet32 (PcdCpuKnownGoodStackSize);
//
// Initialize Gdtr to suppress incorrect compiler/analyzer warnings.
//
Gdtr.Base = 0;
Gdtr.Limit = 0;
SwitchStackData.BufferSize = &BufferSize;
MpInitLibWhoAmI (&Bsp);
for (Index = 0; Index < mNumberOfProcessors; ++Index) {
//
// To support stack switch, we need to re-construct GDT but not IDT.
//
SwitchStackData.Buffer = NULL;
BufferSize = 0;
if (Index == Bsp) {
GetGdtr (&Gdtr);
InitializeExceptionStackSwitchHandlers (&SwitchStackData);
} else {
//
// AP might have different size of GDT from BSP.
// AP might need different buffer size from BSP.
//
MpInitLibStartupThisAP (GetGdtr, Index, NULL, 0, (VOID *)&Gdtr, NULL);
MpInitLibStartupThisAP (InitializeExceptionStackSwitchHandlers, Index, NULL, 0, (VOID *)&SwitchStackData, NULL);
}
//
// X64 needs only one TSS of current task working for all exceptions
// because of its IST feature. IA32 needs one TSS for each exception
// in addition to current task. Since AP is not supposed to allocate
// memory, we have to do it in BSP. To simplify the code, we allocate
// memory for IA32 case to cover both IA32 and X64 exception stack
// switch.
//
// Layout of memory to allocate for each processor:
// --------------------------------
// | Alignment | (just in case)
// --------------------------------
// | |
// | Original GDT |
// | |
// --------------------------------
// | Current task descriptor |
// --------------------------------
// | |
// | Exception task descriptors | X ExceptionNumber
// | |
// --------------------------------
// | Current task-state segment |
// --------------------------------
// | |
// | Exception task-state segment | X ExceptionNumber
// | |
// --------------------------------
//
OldGdtSize = Gdtr.Limit + 1;
EssData.Ia32.ExceptionTssDescSize = sizeof (IA32_TSS_DESCRIPTOR) *
(ExceptionNumber + 1);
EssData.Ia32.ExceptionTssSize = sizeof (IA32_TASK_STATE_SEGMENT) *
(ExceptionNumber + 1);
NewGdtSize = sizeof (IA32_TSS_DESCRIPTOR) +
OldGdtSize +
EssData.Ia32.ExceptionTssDescSize +
EssData.Ia32.ExceptionTssSize;
if (BufferSize == 0) {
continue;
}
GdtBuffer = AllocateRuntimeZeroPool (NewGdtSize);
ASSERT (GdtBuffer != NULL);
//
// Make sure GDT table alignment
//
EssData.Ia32.GdtTable = ALIGN_POINTER (GdtBuffer, sizeof (IA32_TSS_DESCRIPTOR));
NewGdtSize -= ((UINT8 *)EssData.Ia32.GdtTable - GdtBuffer);
EssData.Ia32.GdtTableSize = NewGdtSize;
EssData.Ia32.ExceptionTssDesc = ((UINT8 *)EssData.Ia32.GdtTable + OldGdtSize);
EssData.Ia32.ExceptionTss = ((UINT8 *)EssData.Ia32.GdtTable + OldGdtSize +
EssData.Ia32.ExceptionTssDescSize);
EssData.Ia32.KnownGoodStackTop = (UINTN)StackTop;
SwitchStackData.Buffer = AllocateRuntimeZeroPool (BufferSize);
ASSERT (SwitchStackData.Buffer != NULL);
DEBUG ((
DEBUG_INFO,
"Exception stack top[cpu%lu]: 0x%lX\n",
"Buffer[cpu%lu] for InitializeExceptionStackSwitchHandlers: 0x%lX with size 0x%x\n",
(UINT64)(UINTN)Index,
(UINT64)(UINTN)StackTop
(UINT64)(UINTN)SwitchStackData.Buffer,
(UINT32)BufferSize
));
if (Index == Bsp) {
InitializeExceptionStackSwitchHandlers (&EssData);
InitializeExceptionStackSwitchHandlers (&SwitchStackData);
} else {
MpInitLibStartupThisAP (
InitializeExceptionStackSwitchHandlers,
Index,
NULL,
0,
(VOID *)&EssData,
(VOID *)&SwitchStackData,
NULL
);
}
StackTop -= NewStackSize;
}
}