From 4a0f88dd6458528fc24ad320a05105150c9fb3bb Mon Sep 17 00:00:00 2001 From: Jeff Fan Date: Thu, 10 Nov 2016 13:40:12 +0800 Subject: [PATCH] UefiCpuPkg/PiSmmCpuDxeSmm: Put AP into safe hlt-loop code on S3 path On S3 path, we will wake up APs to restore CPU context in PiSmmCpuDxeSmm driver. However, we place AP in hlt-loop under 1MB space borrowed after CPU restoring CPU contexts. In case, one NMI or SMI happens, APs may exit from hlt state and execute the instruction after HLT instruction. But the code under 1MB is no longer safe at that time. This fix is to allocate one ACPI NVS range to place the AP hlt-loop code. When CPU finished restoration CPU contexts, AP will execute in this ACPI NVS range. https://bugzilla.tianocore.org/show_bug.cgi?id=216 v2: 1. Make stack alignment per Laszlo's comment. 2. Trim whitespace at end of end. 3. Update year mark in file header. Reported-by: Laszlo Ersek Analyzed-by: Paolo Bonzini Analyzed-by: Laszlo Ersek Cc: Laszlo Ersek Cc: Paolo Bonzini Cc: Jiewen Yao Cc: Michael D Kinney Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Jeff Fan Reviewed-by: Paolo Bonzini Reviewed-by: Jiewen Yao Tested-by: Laszlo Ersek --- UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c | 33 +++++++++++++++++++ UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c | 27 ++++++++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h | 13 ++++++++ UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c | 29 +++++++++++++++- 4 files changed, 100 insertions(+), 2 deletions(-) diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c index 6a798ef899..ad7dc412fb 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c @@ -77,6 +77,13 @@ SMM_S3_RESUME_STATE *mSmmS3ResumeState = NULL; BOOLEAN mAcpiS3Enable = TRUE; +UINT8 *mApHltLoopCode = NULL; +UINT8 mApHltLoopCodeTemplate[] = { + 0xFA, // cli + 0xF4, // hlt + 0xEB, 0xFC // jmp $-2 + }; + /** Get MSR spin lock by MSR index. @@ -376,6 +383,8 @@ MPRendezvousProcedure ( CPU_REGISTER_TABLE *RegisterTableList; UINT32 InitApicId; UINTN Index; + UINT32 TopOfStack; + UINT8 Stack[128]; ProgramVirtualWireMode (); DisableLvtInterrupts (); @@ -393,6 +402,14 @@ MPRendezvousProcedure ( // Count down the number with lock mechanism. // InterlockedDecrement (&mNumberToFinish); + + // + // Place AP into the safe code + // + TopOfStack = (UINT32) (UINTN) Stack + sizeof (Stack); + TopOfStack &= ~(UINT32) (CPU_STACK_ALIGNMENT - 1); + CopyMem ((VOID *) (UINTN) mApHltLoopCode, mApHltLoopCodeTemplate, sizeof (mApHltLoopCodeTemplate)); + TransferApToSafeState ((UINT32) (UINTN) mApHltLoopCode, TopOfStack); } /** @@ -731,6 +748,8 @@ InitSmmS3ResumeState ( VOID *GuidHob; EFI_SMRAM_DESCRIPTOR *SmramDescriptor; SMM_S3_RESUME_STATE *SmmS3ResumeState; + EFI_PHYSICAL_ADDRESS Address; + EFI_STATUS Status; if (!mAcpiS3Enable) { return; @@ -773,6 +792,20 @@ InitSmmS3ResumeState ( // Patch SmmS3ResumeState->SmmS3Cr3 // InitSmmS3Cr3 (); + + // + // Allocate safe memory in ACPI NVS for AP to execute hlt loop in + // protected mode on S3 path + // + Address = BASE_4GB - 1; + Status = gBS->AllocatePages ( + AllocateMaxAddress, + EfiACPIMemoryNVS, + EFI_SIZE_TO_PAGES (sizeof (mApHltLoopCodeTemplate)), + &Address + ); + ASSERT_EFI_ERROR (Status); + mApHltLoopCode = (UINT8 *) (UINTN) Address; } /** diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c index 545b534f27..8b880d6ab7 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c @@ -1,7 +1,7 @@ /** @file SMM CPU misc functions for Ia32 arch specific. -Copyright (c) 2015, Intel Corporation. All rights reserved.
+Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.
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 @@ -94,3 +94,28 @@ InitGdt ( *GdtStepSize = GdtTableStepSize; return GdtTssTables; } + +/** + Transfer AP to safe hlt-loop after it finished restore CPU features on S3 patch. + + @param[in] ApHltLoopCode The 32-bit address of the safe hlt-loop function. + @param[in] TopOfStack A pointer to the new stack to use for the ApHltLoopCode. + +**/ +VOID +TransferApToSafeState ( + IN UINT32 ApHltLoopCode, + IN UINT32 TopOfStack + ) +{ + SwitchStack ( + (SWITCH_STACK_ENTRY_POINT) (UINTN) ApHltLoopCode, + NULL, + NULL, + (VOID *) (UINTN) TopOfStack + ); + // + // It should never reach here + // + ASSERT (FALSE); +} diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h index 9b119c8412..6c98659389 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h @@ -825,4 +825,17 @@ GetAcpiS3EnableFlag ( VOID ); +/** + Transfer AP to safe hlt-loop after it finished restore CPU features on S3 patch. + + @param[in] ApHltLoopCode The 32-bit address of the safe hlt-loop function. + @param[in] TopOfStack A pointer to the new stack to use for the ApHltLoopCode. + +**/ +VOID +TransferApToSafeState ( + IN UINT32 ApHltLoopCode, + IN UINT32 TopOfStack + ); + #endif diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c index b53aa45c21..bd465c7a06 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c @@ -1,7 +1,7 @@ /** @file SMM CPU misc functions for x64 arch specific. -Copyright (c) 2015, Intel Corporation. All rights reserved.
+Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.
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 @@ -68,3 +68,30 @@ InitGdt ( *GdtStepSize = GdtTableStepSize; return GdtTssTables; } + +/** + Transfer AP to safe hlt-loop after it finished restore CPU features on S3 patch. + + @param[in] ApHltLoopCode The 32-bit address of the safe hlt-loop function. + @param[in] TopOfStack A pointer to the new stack to use for the ApHltLoopCode. + +**/ +VOID +TransferApToSafeState ( + IN UINT32 ApHltLoopCode, + IN UINT32 TopOfStack + ) +{ + SwitchStack ( + (SWITCH_STACK_ENTRY_POINT) (UINTN) ApHltLoopCode, + NULL, + NULL, + (VOID *) (UINTN) TopOfStack + ); + // + // It should never reach here + // + ASSERT (FALSE); +} + +