Validated-by: Jian J Wang <[email protected]> Reviewed-by: Jian J Wang <[email protected]>
> -----Original Message----- > From: Ni, Ruiyu > Sent: Friday, August 31, 2018 4:36 PM > To: [email protected] > Cc: Wang, Jian J <[email protected]>; Fan Jeff <[email protected]> > Subject: [PATCH 2/2] UefiCpuPkg/CpuExceptionHandlerLib: Avoid calling PEI > services from AP > > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1128 > > When an exception happens in AP, system hangs at > GetPeiServicesTablePointer(), complaining the PeiServices retrieved > from memory before IDT is NULL. > > Due to the following commit: > c563077a380437c114aba4c95be65eb963ebc1f3 > * UefiCpuPkg/MpInitLib: Avoid calling PEI services from AP > the IDT used by AP no longer preserve PeiServices pointer in the > very beginning. > But the implementation of PeiExceptionHandlerLib still assumes > the PeiServices pointer is there, so the assertion happens. > > The patch fixes the exception handler library to not call > PEI services from AP. > > The patch duplicates the #0 exception stub header in an allocated > pool but with extra 4-byte/8-byte to store the exception handler > data which was originally stored in HOB. > When AP exception happens, the code gets the exception handler data > from the exception handler for #0. > > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ruiyu Ni <[email protected]> > Cc: Jian J Wang <[email protected]> > Cc: Fan Jeff <[email protected]> > --- > .../CpuExceptionHandlerLib/CpuExceptionCommon.h | 7 +- > .../CpuExceptionHandlerLib/PeiCpuException.c | 77 > +++++++++++++++------- > 2 files changed, 55 insertions(+), 29 deletions(-) > > diff --git > a/UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.h > b/UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.h > index e10d9379d5..459f06ac84 100644 > --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.h > +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/CpuExceptionCommon.h > @@ -1,7 +1,7 @@ > /** @file > Common header file for CPU Exception Handler Library. > > - Copyright (c) 2012 - 2017, Intel Corporation. All rights reserved.<BR> > + Copyright (c) 2012 - 2018, Intel Corporation. All rights reserved.<BR> > This program and the accompanying materials > are licensed and made available under the terms and conditions of the BSD > License > which accompanies this distribution. The full text of the license may be > found > at > @@ -43,11 +43,6 @@ > > #include "ArchInterruptDefs.h" > > -#define CPU_EXCEPTION_HANDLER_LIB_HOB_GUID \ > - { \ > - 0xb21d9148, 0x9211, 0x4d8f, { 0xad, 0xd3, 0x66, 0xb1, 0x89, 0xc9, 0x2c, > 0x83 } \ > - } > - > #define CPU_STACK_SWITCH_EXCEPTION_NUMBER \ > FixedPcdGetSize (PcdCpuStackSwitchExceptionList) > > diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiCpuException.c > b/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiCpuException.c > index 6f271983f2..5dd8423d2f 100644 > --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiCpuException.c > +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiCpuException.c > @@ -1,7 +1,7 @@ > /** @file > CPU exception handler library implementation for PEIM module. > > -Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR> > +Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR> > This program and the accompanying materials are licensed and made available > under > the terms and conditions of the BSD License that accompanies this > distribution. > The full text of the license may be found at > @@ -20,10 +20,17 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY > KIND, EITHER EXPRESS OR IMPLIED. > > CONST UINTN mDoFarReturnFlag = 0; > > -EFI_GUID mCpuExceptrionHandlerLibHobGuid = > CPU_EXCEPTION_HANDLER_LIB_HOB_GUID; > +typedef struct { > + UINT8 ExceptionStubHeader[HOOKAFTER_STUB_SIZE]; > + EXCEPTION_HANDLER_DATA *ExceptionHandlerData; > +} EXCEPTION0_STUB_HEADER; > > /** > - Get exception handler data pointer from GUIDed HOb. > + Get exception handler data pointer from IDT[0]. > + > + The exception #0 stub header is duplicated in an allocated pool with extra > 4- > byte/8-byte to store the > + exception handler data. The new allocated memory layout follows structure > EXCEPTION0_STUB_HEADER. > + The code assumes that all processors uses the same exception handler for #0 > exception. > > @return pointer to exception handler data. > **/ > @@ -32,18 +39,50 @@ GetExceptionHandlerData ( > VOID > ) > { > - EFI_HOB_GUID_TYPE *GuidHob; > - VOID *DataInHob; > - EXCEPTION_HANDLER_DATA *ExceptionHandlerData; > + IA32_DESCRIPTOR IdtDescriptor; > + IA32_IDT_GATE_DESCRIPTOR *IdtTable; > + EXCEPTION0_STUB_HEADER *Exception0StubHeader; > + > + AsmReadIdtr (&IdtDescriptor); > + IdtTable = (IA32_IDT_GATE_DESCRIPTOR *)IdtDescriptor.Base; > + > + Exception0StubHeader = (EXCEPTION0_STUB_HEADER *)ArchGetIdtHandler > (&IdtTable[0]); > + return Exception0StubHeader->ExceptionHandlerData; > +} > > - ExceptionHandlerData = NULL; > - GuidHob = GetFirstGuidHob (&mCpuExceptrionHandlerLibHobGuid); > - if (GuidHob != NULL) { > - DataInHob = GET_GUID_HOB_DATA (GuidHob); > - ExceptionHandlerData = (EXCEPTION_HANDLER_DATA *)(*(UINTN > *)DataInHob); > - } > - ASSERT (ExceptionHandlerData != NULL); > - return ExceptionHandlerData; > +/** > + Set exception handler data pointer to IDT[0]. > + > + The exception #0 stub header is duplicated in an allocated pool with extra > 4- > byte/8-byte to store the > + exception handler data. The new allocated memory layout follows structure > EXCEPTION0_STUB_HEADER. > + The code assumes that all processors uses the same exception handler for #0 > exception. > + > + @param pointer to exception handler data. > +**/ > +VOID > +SetExceptionHandlerData ( > + IN EXCEPTION_HANDLER_DATA *ExceptionHandlerData > + ) > +{ > + EXCEPTION0_STUB_HEADER *Exception0StubHeader; > + IA32_DESCRIPTOR IdtDescriptor; > + IA32_IDT_GATE_DESCRIPTOR *IdtTable; > + // > + // Duplicate the exception #0 stub header in pool and cache the > ExceptionHandlerData just after the stub header. > + // So AP can get the ExceptionHandlerData by reading the IDT[0]. > + // > + AsmReadIdtr (&IdtDescriptor); > + IdtTable = (IA32_IDT_GATE_DESCRIPTOR *)IdtDescriptor.Base; > + > + Exception0StubHeader = AllocatePool (sizeof (*Exception0StubHeader)); > + ASSERT (Exception0StubHeader != NULL); > + CopyMem ( > + Exception0StubHeader->ExceptionStubHeader, > + (VOID *)ArchGetIdtHandler (&IdtTable[0]), > + sizeof (Exception0StubHeader->ExceptionStubHeader) > + ); > + Exception0StubHeader->ExceptionHandlerData = ExceptionHandlerData; > + ArchUpdateIdtEntry (&IdtTable[0], (UINTN)Exception0StubHeader- > >ExceptionStubHeader); > } > > /** > @@ -109,15 +148,7 @@ InitializeCpuExceptionHandlers ( > return Status; > } > > - // > - // Build location of CPU MP DATA buffer in HOB > - // > - BuildGuidDataHob ( > - &mCpuExceptrionHandlerLibHobGuid, > - (VOID *)&ExceptionHandlerData, > - sizeof(UINT64) > - ); > - > + SetExceptionHandlerData (ExceptionHandlerData); > return EFI_SUCCESS; > } > > -- > 2.16.1.windows.1 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
