From e1f0eed1b2a9954428708bd91243f981e3161301 Mon Sep 17 00:00:00 2001 From: Liming Gao Date: Tue, 14 Jun 2016 16:35:08 +0800 Subject: UefiCpuPkg PiSmmCpuDxeSmm: Update X64/MpFuncs.nasm Use 16bit and 32bit assembly code to replace hard code db. In V2: add 0x67 prefixes to far jumps Without the a32 modifier under FLAT32_JUMP, and the a16 modifier under LONG_JUMP, nasm doesn't generate the 0x67 prefixes, and the far jumps don't work. (For the former, KVM returns an emulation failure. For the latter, KVM performs a triple fault (guest reboot).) By forcing the 0x67 prefixes we end up with the same machine code as the one open-coded in "MpFuncs.asm". This bug breaks S3 resume in the Ia32X64 + SMM_REQUIRE build of OVMF. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Liming Gao Signed-off-by: Laszlo Ersek --- UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm | 94 ++++++++++++++---------------- 1 file changed, 43 insertions(+), 51 deletions(-) (limited to 'UefiCpuPkg/PiSmmCpuDxeSmm') diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm index a10f1ff859..702233d6e4 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/MpFuncs.nasm @@ -45,86 +45,78 @@ extern ASM_PFX(InitializeFloatingPointUnits) DEFAULT REL SECTION .text +BITS 16 global ASM_PFX(RendezvousFunnelProc) ASM_PFX(RendezvousFunnelProc): RendezvousFunnelProcStart: ; At this point CS = 0x(vv00) and ip= 0x0. - db 0x8c, 0xc8 ; mov ax, cs - db 0x8e, 0xd8 ; mov ds, ax - db 0x8e, 0xc0 ; mov es, ax - db 0x8e, 0xd0 ; mov ss, ax - db 0x33, 0xc0 ; xor ax, ax - db 0x8e, 0xe0 ; mov fs, ax - db 0x8e, 0xe8 ; mov gs, ax + mov ax, cs + mov ds, ax + mov es, ax + mov ss, ax + xor ax, ax + mov fs, ax + mov gs, ax flat32Start: - db 0xBE - dw BufferStartLocation ; mov si, BufferStartLocation - db 0x66, 0x8B, 0x14 ; mov edx,dword ptr [si] ; EDX is keeping the start address of wakeup buffer + mov si, BufferStartLocation + mov edx,dword [si] ; EDX is keeping the start address of wakeup buffer - db 0xBE - dw Cr3OffsetLocation ; mov si, Cr3Location - db 0x66, 0x8B, 0xC ; mov ecx,dword ptr [si] ; ECX is keeping the value of CR3 + mov si, Cr3OffsetLocation + mov ecx,dword [si] ; ECX is keeping the value of CR3 - db 0xBE - dw GdtrLocation ; mov si, GdtrProfile - db 0x66 ; db 66h - db 0x2E, 0xF, 0x1, 0x14 ; lgdt fword ptr cs:[si] + mov si, GdtrLocation +o32 lgdt [cs:si] - db 0xBE - dw IdtrLocation ; mov si, IdtrProfile - db 0x66 ; db 66h - db 0x2E, 0xF, 0x1, 0x1C ; lidt fword ptr cs:[si] + mov si, IdtrLocation +o32 lidt [cs:si] - db 0x33, 0xC0 ; xor ax, ax - db 0x8E, 0xD8 ; mov ds, ax + xor ax, ax + mov ds, ax - db 0xF, 0x20, 0xC0 ; mov eax, cr0 ; Get control register 0 - db 0x66, 0x83, 0xC8, 0x1 ; or eax, 000000001h ; Set PE bit (bit #0) - db 0xF, 0x22, 0xC0 ; mov cr0, eax + mov eax, cr0 ; Get control register 0 + or eax, 0x000000001 ; Set PE bit (bit #0) + mov cr0, eax FLAT32_JUMP: - db 0x66, 0x67, 0xEA ; far jump - dd 0x0 ; 32-bit offset - dw 0x20 ; 16-bit selector +a32 jmp dword 0x20:0x0 +BITS 32 PMODE_ENTRY: ; protected mode entry point - db 0x66, 0xB8, 0x18, 0x0 ; mov ax, 18h - db 0x66, 0x8E, 0xD8 ; mov ds, ax - db 0x66, 0x8E, 0xC0 ; mov es, ax - db 0x66, 0x8E, 0xE0 ; mov fs, ax - db 0x66, 0x8E, 0xE8 ; mov gs, ax - db 0x66, 0x8E, 0xD0 ; mov ss, ax ; Flat mode setup. + mov ax, 0x18 +o16 mov ds, ax +o16 mov es, ax +o16 mov fs, ax +o16 mov gs, ax +o16 mov ss, ax ; Flat mode setup. - db 0xF, 0x20, 0xE0 ; mov eax, cr4 - db 0xF, 0xBA, 0xE8, 0x5 ; bts eax, 5 - db 0xF, 0x22, 0xE0 ; mov cr4, eax + mov eax, cr4 + bts eax, 5 + mov cr4, eax - db 0xF, 0x22, 0xD9 ; mov cr3, ecx + mov cr3, ecx - db 0x8B, 0xF2 ; mov esi, edx ; Save wakeup buffer address + mov esi, edx ; Save wakeup buffer address - db 0xB9 - dd 0xC0000080 ; mov ecx, 0c0000080h ; EFER MSR number. - db 0xF, 0x32 ; rdmsr ; Read EFER. - db 0xF, 0xBA, 0xE8, 0x8 ; bts eax, 8 ; Set LME=1. - db 0xF, 0x30 ; wrmsr ; Write EFER. + mov ecx, 0xc0000080 ; EFER MSR number. + rdmsr ; Read EFER. + bts eax, 8 ; Set LME=1. + wrmsr ; Write EFER. - db 0xF, 0x20, 0xC0 ; mov eax, cr0 ; Read CR0. - db 0xF, 0xBA, 0xE8, 0x1F ; bts eax, 31 ; Set PG=1. - db 0xF, 0x22, 0xC0 ; mov cr0, eax ; Write CR0. + mov eax, cr0 ; Read CR0. + bts eax, 31 ; Set PG=1. + mov cr0, eax ; Write CR0. LONG_JUMP: - db 0x67, 0xEA ; far jump - dd 0x0 ; 32-bit offset - dw 0x38 ; 16-bit selector +a16 jmp dword 0x38:0x0 +BITS 64 LongModeStart: mov ax, 0x30 -- cgit v1.2.3