From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=66.187.233.73; helo=mx1.redhat.com; envelope-from=lersek@redhat.com; receiver=edk2-devel@lists.01.org Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 780E1225E4022 for ; Fri, 23 Mar 2018 14:08:54 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4C30D230EE2; Fri, 23 Mar 2018 21:15:27 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-180.rdu2.redhat.com [10.10.120.180]) by smtp.corp.redhat.com (Postfix) with ESMTP id 94F4B2166BAE; Fri, 23 Mar 2018 21:15:26 +0000 (UTC) From: Laszlo Ersek To: edk2-devel-01 Cc: Eric Dong , Michael D Kinney Date: Fri, 23 Mar 2018 22:15:01 +0100 Message-Id: <20180323211504.22434-13-lersek@redhat.com> In-Reply-To: <20180323211504.22434-1-lersek@redhat.com> References: <20180323211504.22434-1-lersek@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Fri, 23 Mar 2018 21:15:27 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Fri, 23 Mar 2018 21:15:27 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'lersek@redhat.com' RCPT:'' Subject: [PATCH v2 12/15] UefiCpuPkg/PiSmmCpuDxeSmm: eliminate "gSmmJmpAddr" and related DBs X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Mar 2018 21:08:54 -0000 The IA32 version of "SmmInit.nasm" does not need "gSmmJmpAddr" at all (its PiSmmCpuSmmInitFixupAddress() variant doesn't do anything either). We can simply use the NASM syntax for the following Mixed-Size Jump: > jmp PROTECT_MODE_CS : dword @32bit The generated object code for the instruction is unchanged: > 00000182 66EA5A0000000800 jmp dword 0x8:0x5a (The NASM manual explains that putting the DWORD prefix after the colon ":" reflects the intent better, since it is the offset that is a DWORD. Thus, that's what I used. However, both syntaxes are interchangeable, hence the ndisasm output.) The X64 version of "SmmInit.nasm" appears to require "gSmmJmpAddr"; however that's accidental, not inherent: - Bring LONG_MODE_CODE_SEGMENT from "UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h" to "SmmInit.nasm" as LONG_MODE_CS, same as PROTECT_MODE_CODE_SEGMENT was brought to the IA32 version as PROTECT_MODE_CS earlier. - Apply the NASM-native Mixed-Size Jump syntax again, but jump to the fixed zero offset in LONG_MODE_CS. This will produce no relocation record at all. Add a label after the instruction. - Modify PiSmmCpuSmmInitFixupAddress() to patch the jump target backwards from the label. Because we modify the DWORD offset with a DWORD access, the segment selector is unharmed in the instruction, and we need not set it from PiCpuSmmEntry(). According to "objdump --reloc", the X64 version undergoes only the following relocations, after this patch: > RELOCATION RECORDS FOR [.text]: > OFFSET TYPE VALUE > 0000000000000095 R_X86_64_PC32 SmmInitHandler-0x0000000000000004 > 00000000000000e0 R_X86_64_PC32 mRebasedFlag-0x0000000000000004 > 00000000000000ea R_X86_64_PC32 mSmmRelocationOriginalAddress-0x0000000000000004 Therefore the patch does not regress ("Enable XCODE5 tool chain for UefiCpuPkg with nasm source code"). Cc: Eric Dong Cc: Michael D Kinney Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866 Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Laszlo Ersek --- Notes: v2: - no change UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h | 11 ----------- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmInit.nasm | 6 +----- UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm | 11 ++++++----- UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c | 7 ------- 4 files changed, 7 insertions(+), 28 deletions(-) diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h index 62e4e38e9f2a..856d5738c081 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h @@ -295,17 +295,6 @@ WriteSaveStateRegister ( IN CONST VOID *Buffer ); -// -// -// -typedef struct { - UINT32 Offset; - UINT16 Segment; - UINT16 Reserved; -} IA32_FAR_ADDRESS; - -extern IA32_FAR_ADDRESS gSmmJmpAddr; - extern CONST UINT8 gcSmmInitTemplate[]; extern CONST UINT16 gcSmmInitSize; X86_ASSEMBLY_PATCH_LABEL gPatchSmmCr0; diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmInit.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmInit.nasm index 0f62fe448712..f59413d9d4a3 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmInit.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmInit.nasm @@ -25,7 +25,6 @@ extern ASM_PFX(mSmmRelocationOriginalAddress) global ASM_PFX(gPatchSmmCr3) global ASM_PFX(gPatchSmmCr4) global ASM_PFX(gPatchSmmCr0) -global ASM_PFX(gSmmJmpAddr) global ASM_PFX(gSmmInitStack) global ASM_PFX(gcSmiInitGdtr) global ASM_PFX(gcSmmInitSize) @@ -64,10 +63,7 @@ ASM_PFX(gPatchSmmCr4): ASM_PFX(gPatchSmmCr0): mov di, PROTECT_MODE_DS mov cr0, eax - DB 0x66, 0xea ; jmp far [ptr48] -ASM_PFX(gSmmJmpAddr): - DD @32bit - DW PROTECT_MODE_CS + jmp PROTECT_MODE_CS : dword @32bit BITS 32 @32bit: diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm index 1a0667bd97ba..2460e1eb2dee 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm @@ -25,7 +25,6 @@ extern ASM_PFX(mSmmRelocationOriginalAddress) global ASM_PFX(gPatchSmmCr3) global ASM_PFX(gPatchSmmCr4) global ASM_PFX(gPatchSmmCr0) -global ASM_PFX(gSmmJmpAddr) global ASM_PFX(gSmmInitStack) global ASM_PFX(gcSmiInitGdtr) global ASM_PFX(gcSmmInitSize) @@ -33,6 +32,8 @@ global ASM_PFX(gcSmmInitTemplate) global ASM_PFX(mRebasedFlagAddr32) global ASM_PFX(mSmmRelocationOriginalAddressPtr32) +%define LONG_MODE_CS 0x38 + DEFAULT REL SECTION .text @@ -66,8 +67,8 @@ ASM_PFX(gPatchSmmCr4): mov eax, strict dword 0 ; source operand will be patched ASM_PFX(gPatchSmmCr0): mov cr0, eax ; enable protected mode & paging - DB 0x66, 0xea ; far jmp to long mode -ASM_PFX(gSmmJmpAddr): DQ 0;@LongMode + jmp LONG_MODE_CS : dword 0 ; offset will be patched to @LongMode +@PatchLongModeOffset: BITS 64 @LongMode: ; long-mode starts here @@ -141,8 +142,8 @@ ASM_PFX(mSmmRelocationOriginalAddressPtr32): dd 0 global ASM_PFX(PiSmmCpuSmmInitFixupAddress) ASM_PFX(PiSmmCpuSmmInitFixupAddress): lea rax, [@LongMode] - lea rcx, [ASM_PFX(gSmmJmpAddr)] - mov qword [rcx], rax + lea rcx, [@PatchLongModeOffset - 6] + mov dword [rcx], eax lea rax, [ASM_PFX(SmmStartup)] lea rcx, [@L1] diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c index f602d86d51a1..0c8a4543d865 100755 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c @@ -569,13 +569,6 @@ PiCpuSmmEntry ( EFI_COMPUTING_UNIT_HOST_PROCESSOR | EFI_CU_HP_PC_SMM_INIT ); - // - // Fix segment address of the long-mode-switch jump - // - if (sizeof (UINTN) == sizeof (UINT64)) { - gSmmJmpAddr.Segment = LONG_MODE_CODE_SEGMENT; - } - // // Find out SMRR Base and SMRR Size // -- 2.14.1.3.gb7cf6e02401b