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CpuException: Add InitializeSeparateExceptionStacks

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Today InitializeCpuExceptionHandlersEx is called from three modules:
1. DxeCore (links to DxeCpuExceptionHandlerLib)
    DxeCore expects it initializes the IDT entries as well as
    assigning separate stacks for #DF and #PF.
2. CpuMpPei (links to PeiCpuExceptionHandlerLib)
   and CpuDxe (links to DxeCpuExceptionHandlerLib)
    It's called for each thread for only assigning separate stacks for
    #DF and #PF. The IDT entries initialization is skipped because
    caller sets InitData->X64.InitDefaultHandlers to FALSE.

Additionally, SecPeiCpuExceptionHandlerLib, SmmCpuExceptionHandlerLib
also implement such API and the behavior of the API is simply to initialize
IDT entries only.

Because it mixes the IDT entries initialization and separate stacks
assignment for certain exception handlers together, in order to know
whether the function call only initializes IDT entries, or assigns stacks,
we need to check:
1. value of InitData->X64.InitDefaultHandlers
2. library instance

This patch cleans up the code to separate the stack assignment to a new API:
InitializeSeparateExceptionStacks().

Only when caller calls the new API, the separate stacks are assigned.
With this change, the SecPei and Smm instance can return unsupported which
gives caller a very clear status.

The old API InitializeCpuExceptionHandlersEx() is removed in this patch.
Because no platform module is consuming the old API, the impact is none.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
This commit is contained in:
Ray Ni
2022-05-20 19:12:35 +08:00
committed by mergify[bot]
parent 2a09527ebc
commit e7abb94d1f
9 changed files with 74 additions and 184 deletions
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24
MdeModulePkg/Include/Library/CpuExceptionHandlerLib.h
View File

@ -103,32 +103,20 @@ InitializeCpuExceptionHandlers (
);
/**
Initializes all CPU exceptions entries with optional extra initializations.
Setup separate stacks for certain exception handlers.
By default, this method should include all functionalities implemented by
InitializeCpuExceptionHandlers(), plus extra initialization works, if any.
This could be done by calling InitializeCpuExceptionHandlers() directly
in this method besides the extra works.
InitData is optional and processor arch dependent.
InitData is optional and its use and content are processor arch dependent.
The typical usage of it is to convey resources which have to be reserved
elsewhere and are necessary for the extra initializations of exception.
@param[in] InitData Pointer to data optional for information about how
to assign stacks for certain exception handlers.
@param[in] VectorInfo Pointer to reserved vector list.
@param[in] InitData Pointer to data optional for extra initializations
of exception.
@retval EFI_SUCCESS The exceptions have been successfully
initialized.
@retval EFI_INVALID_PARAMETER VectorInfo or InitData contains invalid
content.
@retval EFI_SUCCESS The stacks are assigned successfully.
@retval EFI_UNSUPPORTED This function is not supported.
**/
EFI_STATUS
EFIAPI
InitializeCpuExceptionHandlersEx (
IN EFI_VECTOR_HANDOFF_INFO *VectorInfo OPTIONAL,
InitializeSeparateExceptionStacks (
IN CPU_EXCEPTION_INIT_DATA *InitData OPTIONAL
);