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#------------------------------------------------------------------------------
#
# Copyright (c) 2009 - 2016, 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
# http://opensource.org/licenses/bsd-license.php.
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
# Module Name:
#
# SmiException.S
#
# Abstract:
#
# Exception handlers used in SM mode
#
#------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(SmiPFHandler)
ASM_GLOBAL ASM_PFX(gcSmiIdtr)
ASM_GLOBAL ASM_PFX(gcSmiGdtr)
ASM_GLOBAL ASM_PFX(gcPsd)
.data
NullSeg: .quad 0 # reserved by architecture
CodeSeg32:
.word -1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x9b
.byte 0xcf # LimitHigh
.byte 0 # BaseHigh
ProtModeCodeSeg32:
.word -1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x9b
.byte 0xcf # LimitHigh
.byte 0 # BaseHigh
ProtModeSsSeg32:
.word -1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x93
.byte 0xcf # LimitHigh
.byte 0 # BaseHigh
DataSeg32:
.word -1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x93
.byte 0xcf # LimitHigh
.byte 0 # BaseHigh
CodeSeg16:
.word -1
.word 0
.byte 0
.byte 0x9b
.byte 0x8f
.byte 0
DataSeg16:
.word -1
.word 0
.byte 0
.byte 0x93
.byte 0x8f
.byte 0
CodeSeg64:
.word -1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x9b
.byte 0xaf # LimitHigh
.byte 0 # BaseHigh
# TSS Segment for X64 specially
TssSeg:
.word TSS_DESC_SIZE - 1 # LimitLow
.word 0 # BaseLow
.byte 0 # BaseMid
.byte 0x89
.byte 0x00 # LimitHigh
.byte 0 # BaseHigh
.long 0 # BaseUpper
.long 0 # Reserved
.equ GDT_SIZE, .- NullSeg
TssDescriptor:
.space 104, 0
.equ TSS_DESC_SIZE, .- TssDescriptor
#
# This structure serves as a template for all processors.
#
ASM_PFX(gcPsd):
.ascii "PSDSIG "
.word PSD_SIZE
.word 2
.word 1 << 2
.word CODE_SEL
.word DATA_SEL
.word DATA_SEL
.word DATA_SEL
.word 0
.quad 0
.quad 0
.quad 0 # fixed in InitializeMpServiceData()
.quad NullSeg
.long GDT_SIZE
.long 0
.space 24, 0
.quad 0
.equ PSD_SIZE, . - ASM_PFX(gcPsd)
#
# CODE & DATA segments for SMM runtime
#
.equ CODE_SEL, CodeSeg64 - NullSeg
.equ DATA_SEL, DataSeg32 - NullSeg
.equ CODE32_SEL, CodeSeg32 - NullSeg
ASM_PFX(gcSmiGdtr):
.word GDT_SIZE - 1
.quad NullSeg
ASM_PFX(gcSmiIdtr):
.word 0
.quad 0
.text
#------------------------------------------------------------------------------
# _SmiExceptionEntryPoints is the collection of exception entry points followed
# by a common exception handler.
#
# Stack frame would be as follows as specified in IA32 manuals:
# +---------------------+ <-- 16-byte aligned ensured by processor
# + Old SS +
# +---------------------+
# + Old RSP +
# +---------------------+
# + RFlags +
# +---------------------+
# + CS +
# +---------------------+
# + RIP +
# +---------------------+
# + Error Code +
# +---------------------+
# + Vector Number +
# +---------------------+
# + RBP +
# +---------------------+ <-- RBP, 16-byte aligned
#
# RSP set to odd multiple of 8 at @CommonEntryPoint means ErrCode PRESENT
#------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(PageFaultIdtHandlerSmmProfile)
ASM_PFX(PageFaultIdtHandlerSmmProfile):
pushq $0x0e # Page Fault
.byte 0x40, 0xf6, 0xc4, 0x08 #test spl, 8
jnz L1
pushq (%rsp)
movq $0, 8(%rsp)
L1:
pushq %rbp
movq %rsp, %rbp
#
# Since here the stack pointer is 16-byte aligned, so
# EFI_FX_SAVE_STATE_X64 of EFI_SYSTEM_CONTEXT_x64
# is 16-byte aligned
#
## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
pushq %r15
pushq %r14
pushq %r13
pushq %r12
pushq %r11
pushq %r10
pushq %r9
pushq %r8
pushq %rax
pushq %rcx
pushq %rdx
pushq %rbx
pushq 48(%rbp) # RSP
pushq (%rbp) # RBP
pushq %rsi
pushq %rdi
## UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero
movzwq 56(%rbp), %rax
pushq %rax # for ss
movzwq 32(%rbp), %rax
pushq %rax # for cs
movq %ds, %rax
pushq %rax
movq %es, %rax
pushq %rax
movq %fs, %rax
pushq %rax
movq %gs, %rax
pushq %rax
## UINT64 Rip;
pushq 24(%rbp)
## UINT64 Gdtr[2], Idtr[2];
subq $16, %rsp
sidt (%rsp)
subq $16, %rsp
sgdt (%rsp)
## UINT64 Ldtr, Tr;
xorq %rax, %rax
strw %ax
pushq %rax
sldtw %ax
pushq %rax
## UINT64 RFlags;
pushq 40(%rbp)
## UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
movq %cr8, %rax
pushq %rax
movq %cr4, %rax
orq $0x208, %rax
movq %rax, %cr4
pushq %rax
movq %cr3, %rax
pushq %rax
movq %cr2, %rax
pushq %rax
xorq %rax, %rax
pushq %rax
movq %cr0, %rax
pushq %rax
## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
movq %dr7, %rax
pushq %rax
movq %dr6, %rax
pushq %rax
movq %dr3, %rax
pushq %rax
movq %dr2, %rax
pushq %rax
movq %dr1, %rax
pushq %rax
movq %dr0, %rax
pushq %rax
## FX_SAVE_STATE_X64 FxSaveState;
subq $512, %rsp
movq %rsp, %rdi
.byte 0xf, 0xae, 0x7 # fxsave [rdi]
# UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
cld
## UINT32 ExceptionData;
pushq 16(%rbp)
## call into exception handler
movq 8(%rbp), %rcx
movabsq $ASM_PFX(SmiPFHandler), %rax
## Prepare parameter and call
movq %rsp, %rdx
#
# Per X64 calling convention, allocate maximum parameter stack space
# and make sure RSP is 16-byte aligned
#
subq $4 * 8 + 8, %rsp
call *%rax
addq $4 * 8 + 8, %rsp
jmp L5
L5:
## UINT64 ExceptionData;
addq $8, %rsp
## FX_SAVE_STATE_X64 FxSaveState;
movq %rsp, %rsi
.byte 0xf, 0xae, 0xe # fxrstor [rsi]
addq $512, %rsp
## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
## Skip restoration of DRx registers to support debuggers
## that set breakpoints in interrupt/exception context
addq $8 * 6, %rsp
## UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
popq %rax
movq %rax, %cr0
addq $8, %rsp # not for Cr1
popq %rax
movq %rax, %cr2
popq %rax
movq %rax, %cr3
popq %rax
movq %rax, %cr4
popq %rax
movq %rax, %cr8
## UINT64 RFlags;
popq 40(%rbp)
## UINT64 Ldtr, Tr;
## UINT64 Gdtr[2], Idtr[2];
## Best not let anyone mess with these particular registers...
addq $48, %rsp
## UINT64 Rip;
popq 24(%rbp)
## UINT64 Gs, Fs, Es, Ds, Cs, Ss;
popq %rax
# mov gs, rax ; not for gs
popq %rax
# mov fs, rax ; not for fs
# (X64 will not use fs and gs, so we do not restore it)
popq %rax
movq %rax, %es
popq %rax
movq %rax, %ds
popq 32(%rbp) # for cs
popq 56(%rbp) # for ss
## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
popq %rdi
popq %rsi
addq $8, %rsp # not for rbp
popq 48(%rbp) # for rsp
popq %rbx
popq %rdx
popq %rcx
popq %rax
popq %r8
popq %r9
popq %r10
popq %r11
popq %r12
popq %r13
popq %r14
popq %r15
movq %rbp, %rsp
# Enable TF bit after page fault handler runs
btsl $8, 40(%rsp) #RFLAGS
popq %rbp
addq $16, %rsp # skip INT# & ErrCode
iretq
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