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[76.210.143.223]) by smtp.gmail.com with ESMTPSA id x28sm16401572pfj.73.2020.08.25.11.04.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2020 11:04:14 -0700 (PDT) Date: Tue, 25 Aug 2020 11:04:14 -0700 (PDT) X-Google-Original-Date: Tue, 25 Aug 2020 10:31:55 PDT (-0700) Subject: Re: [PATCH v6 5/9] RISC-V: Add PE/COFF header for EFI stub In-Reply-To: <20200819222425.30721-6-atish.patra@wdc.com> CC: linux-kernel@vger.kernel.org, Atish Patra , ardb@kernel.org, anup@brainfault.org, Alistair Francis , Anup Patel , nivedita@alum.mit.edu, Damien Le Moal , greentime.hu@sifive.com, hca@linux.ibm.com, mingo@kernel.org, keescook@chromium.org, linux-efi@vger.kernel.org, linux-riscv@lists.infradead.org, masahiroy@kernel.org, michal.simek@xilinx.com, rppt@kernel.org, Nick Desaulniers , Paul Walmsley , steven.price@arm.com, longman@redhat.com, zong.li@sifive.com, daniel.schaefer@hpe.com, abner.chang@hpe.com From: Palmer Dabbelt To: Atish Patra Message-ID: Mime-Version: 1.0 (MHng) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 19 Aug 2020 15:24:21 PDT (-0700), Atish Patra wrote: > Linux kernel Image can appear as an EFI application With appropriate > PE/COFF header fields in the beginning of the Image header. An EFI > application loader can directly load a Linux kernel Image and an EFI > stub residing in kernel can boot Linux kernel directly. > > Add the necessary PE/COFF header. > > Signed-off-by: Atish Patra > Link: https://lore.kernel.org/r/20200421033336.9663-3-atish.patra@wdc.com > [ardb: - use C prefix for c.li to ensure the expected opcode is emitted > - align all image sections according to PE/COFF section alignment ] > Signed-off-by: Ard Biesheuvel > Reviewed-by: Anup Patel > --- > arch/riscv/include/asm/sections.h | 13 ++++ > arch/riscv/kernel/Makefile | 4 ++ > arch/riscv/kernel/efi-header.S | 104 ++++++++++++++++++++++++++++++ > arch/riscv/kernel/head.S | 16 +++++ > arch/riscv/kernel/image-vars.h | 51 +++++++++++++++ > arch/riscv/kernel/vmlinux.lds.S | 22 ++++++- > 6 files changed, 208 insertions(+), 2 deletions(-) > create mode 100644 arch/riscv/include/asm/sections.h > create mode 100644 arch/riscv/kernel/efi-header.S > create mode 100644 arch/riscv/kernel/image-vars.h > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h > new file mode 100644 > index 000000000000..3a9971b1210f > --- /dev/null > +++ b/arch/riscv/include/asm/sections.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + */ > +#ifndef __ASM_SECTIONS_H > +#define __ASM_SECTIONS_H > + > +#include > + > +extern char _start[]; > +extern char _start_kernel[]; > + > +#endif /* __ASM_SECTIONS_H */ > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile > index a5287ab9f7f2..eabec4dce50b 100644 > --- a/arch/riscv/kernel/Makefile > +++ b/arch/riscv/kernel/Makefile > @@ -32,6 +32,10 @@ obj-y += patch.o > obj-$(CONFIG_MMU) += vdso.o vdso/ > > obj-$(CONFIG_RISCV_M_MODE) += clint.o traps_misaligned.o > +OBJCOPYFLAGS := --prefix-symbols=__efistub_ > +$(obj)/%.stub.o: $(obj)/%.o FORCE > + $(call if_changed,objcopy) > + Is there a reason this is below those objects? I don't really care, but it triggered a merge conflict and it seems cleaner above so I put it up there. > obj-$(CONFIG_FPU) += fpu.o > obj-$(CONFIG_SMP) += smpboot.o > obj-$(CONFIG_SMP) += smp.o > diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S > new file mode 100644 > index 000000000000..822b4c9ff2bb > --- /dev/null > +++ b/arch/riscv/kernel/efi-header.S > @@ -0,0 +1,104 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * Adapted from arch/arm64/kernel/efi-header.S > + */ > + > +#include > +#include > + > + .macro __EFI_PE_HEADER > + .long PE_MAGIC > +coff_header: > +#ifdef CONFIG_64BIT > + .short IMAGE_FILE_MACHINE_RISCV64 // Machine > +#else > + .short IMAGE_FILE_MACHINE_RISCV32 // Machine > +#endif > + .short section_count // NumberOfSections > + .long 0 // TimeDateStamp > + .long 0 // PointerToSymbolTable > + .long 0 // NumberOfSymbols > + .short section_table - optional_header // SizeOfOptionalHeader > + .short IMAGE_FILE_DEBUG_STRIPPED | \ > + IMAGE_FILE_EXECUTABLE_IMAGE | \ > + IMAGE_FILE_LINE_NUMS_STRIPPED // Characteristics > + > +optional_header: > + .short PE_OPT_MAGIC_PE32PLUS // PE32+ format > + .byte 0x02 // MajorLinkerVersion > + .byte 0x14 // MinorLinkerVersion > + .long __pecoff_text_end - efi_header_end // SizeOfCode > + .long __pecoff_data_virt_size // SizeOfInitializedData > + .long 0 // SizeOfUninitializedData > + .long __efistub_efi_pe_entry - _start // AddressOfEntryPoint > + .long efi_header_end - _start // BaseOfCode > + > +extra_header_fields: > + .quad 0 // ImageBase > + .long PECOFF_SECTION_ALIGNMENT // SectionAlignment > + .long PECOFF_FILE_ALIGNMENT // FileAlignment > + .short 0 // MajorOperatingSystemVersion > + .short 0 // MinorOperatingSystemVersion > + .short LINUX_EFISTUB_MAJOR_VERSION // MajorImageVersion > + .short LINUX_EFISTUB_MINOR_VERSION // MinorImageVersion > + .short 0 // MajorSubsystemVersion > + .short 0 // MinorSubsystemVersion > + .long 0 // Win32VersionValue > + > + .long _end - _start // SizeOfImage > + > + // Everything before the kernel image is considered part of the header > + .long efi_header_end - _start // SizeOfHeaders > + .long 0 // CheckSum > + .short IMAGE_SUBSYSTEM_EFI_APPLICATION // Subsystem > + .short 0 // DllCharacteristics > + .quad 0 // SizeOfStackReserve > + .quad 0 // SizeOfStackCommit > + .quad 0 // SizeOfHeapReserve > + .quad 0 // SizeOfHeapCommit > + .long 0 // LoaderFlags > + .long (section_table - .) / 8 // NumberOfRvaAndSizes > + > + .quad 0 // ExportTable > + .quad 0 // ImportTable > + .quad 0 // ResourceTable > + .quad 0 // ExceptionTable > + .quad 0 // CertificationTable > + .quad 0 // BaseRelocationTable > + > + // Section table > +section_table: > + .ascii ".text\0\0\0" > + .long __pecoff_text_end - efi_header_end // VirtualSize > + .long efi_header_end - _start // VirtualAddress > + .long __pecoff_text_end - efi_header_end // SizeOfRawData > + .long efi_header_end - _start // PointerToRawData > + > + .long 0 // PointerToRelocations > + .long 0 // PointerToLineNumbers > + .short 0 // NumberOfRelocations > + .short 0 // NumberOfLineNumbers > + .long IMAGE_SCN_CNT_CODE | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_EXECUTE // Characteristics > + > + .ascii ".data\0\0\0" > + .long __pecoff_data_virt_size // VirtualSize > + .long __pecoff_text_end - _start // VirtualAddress > + .long __pecoff_data_raw_size // SizeOfRawData > + .long __pecoff_text_end - _start // PointerToRawData > + > + .long 0 // PointerToRelocations > + .long 0 // PointerToLineNumbers > + .short 0 // NumberOfRelocations > + .short 0 // NumberOfLineNumbers > + .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_WRITE // Characteristics > + > + .set section_count, (. - section_table) / 40 > + > + .balign 0x1000 > +efi_header_end: > + .endm > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > index c6a37e8231a8..3631147732ee 100644 > --- a/arch/riscv/kernel/head.S > +++ b/arch/riscv/kernel/head.S > @@ -13,6 +13,7 @@ > #include > #include > #include > +#include "efi-header.S" > > __HEAD > ENTRY(_start) > @@ -22,10 +23,18 @@ ENTRY(_start) > * Do not modify it without modifying the structure and all bootloaders > * that expects this header format!! > */ > +#ifdef CONFIG_EFI > + /* > + * This instruction decodes to "MZ" ASCII required by UEFI. > + */ > + c.li s4,-13 > + j _start_kernel > +#else > /* jump to start kernel */ > j _start_kernel > /* reserved */ > .word 0 > +#endif > .balign 8 > #if __riscv_xlen == 64 > /* Image load offset(2MB) from start of RAM */ > @@ -43,7 +52,14 @@ ENTRY(_start) > .ascii RISCV_IMAGE_MAGIC > .balign 4 > .ascii RISCV_IMAGE_MAGIC2 > +#ifdef CONFIG_EFI > + .word pe_head_start - _start > +pe_head_start: > + > + __EFI_PE_HEADER > +#else > .word 0 > +#endif > > .align 2 > #ifdef CONFIG_MMU > diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h > new file mode 100644 > index 000000000000..8c212efb37a6 > --- /dev/null > +++ b/arch/riscv/kernel/image-vars.h > @@ -0,0 +1,51 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * Linker script variables to be set after section resolution, as > + * ld.lld does not like variables assigned before SECTIONS is processed. > + * Based on arch/arm64/kerne/image-vars.h > + */ > +#ifndef __RISCV_KERNEL_IMAGE_VARS_H > +#define __RISCV_KERNEL_IMAGE_VARS_H > + > +#ifndef LINKER_SCRIPT > +#error This file should only be included in vmlinux.lds.S > +#endif > + > +#ifdef CONFIG_EFI > + > +/* > + * The EFI stub has its own symbol namespace prefixed by __efistub_, to > + * isolate it from the kernel proper. The following symbols are legally > + * accessed by the stub, so provide some aliases to make them accessible. > + * Only include data symbols here, or text symbols of functions that are > + * guaranteed to be safe when executed at another offset than they were > + * linked at. The routines below are all implemented in assembler in a > + * position independent manner > + */ > +__efistub_memcmp = memcmp; > +__efistub_memchr = memchr; > +__efistub_memcpy = memcpy; > +__efistub_memmove = memmove; > +__efistub_memset = memset; > +__efistub_strlen = strlen; > +__efistub_strnlen = strnlen; > +__efistub_strcmp = strcmp; > +__efistub_strncmp = strncmp; > +__efistub_strrchr = strrchr; > + > +#ifdef CONFIG_KASAN > +__efistub___memcpy = memcpy; > +__efistub___memmove = memmove; > +__efistub___memset = memset; > +#endif > + > +__efistub__start = _start; > +__efistub__start_kernel = _start_kernel; > +__efistub__end = _end; > +__efistub__edata = _edata; > +__efistub_screen_info = screen_info; > + > +#endif > + > +#endif /* __RISCV_KERNEL_IMAGE_VARS_H */ > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > index f3586e31ed1e..6dcf790282dd 100644 > --- a/arch/riscv/kernel/vmlinux.lds.S > +++ b/arch/riscv/kernel/vmlinux.lds.S > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include "image-vars.h" > > #include > OUTPUT_ARCH(riscv) > @@ -17,6 +18,9 @@ ENTRY(_start) > > jiffies = jiffies_64; > > +PECOFF_SECTION_ALIGNMENT = 0x1000; > +PECOFF_FILE_ALIGNMENT = 0x200; > + > SECTIONS > { > /* Beginning of code and text segment */ > @@ -76,6 +80,10 @@ SECTIONS > > EXCEPTION_TABLE(0x10) > > +#ifdef CONFIG_EFI > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > + __pecoff_text_end = .; > +#endif > . = ALIGN(SECTION_ALIGN); > _data = .; > > @@ -83,16 +91,26 @@ SECTIONS > .sdata : { > __global_pointer$ = . + 0x800; > *(.sdata*) > - /* End of data section */ > - _edata = .; > } > > +#ifdef CONFIG_EFI > + .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); } > + __pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end); > +#endif > + > + /* End of data section */ > + _edata = .; > + > BSS_SECTION(PAGE_SIZE, PAGE_SIZE, 0) > > .rel.dyn : { > *(.rel.dyn*) > } > > +#ifdef CONFIG_EFI > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > + __pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end); > +#endif > _end = .; > > STABS_DEBUG From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9E196C433E3 for ; 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[76.210.143.223]) by smtp.gmail.com with ESMTPSA id x28sm16401572pfj.73.2020.08.25.11.04.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2020 11:04:14 -0700 (PDT) Date: Tue, 25 Aug 2020 11:04:14 -0700 (PDT) X-Google-Original-Date: Tue, 25 Aug 2020 10:31:55 PDT (-0700) Subject: Re: [PATCH v6 5/9] RISC-V: Add PE/COFF header for EFI stub In-Reply-To: <20200819222425.30721-6-atish.patra@wdc.com> From: Palmer Dabbelt To: Atish Patra Message-ID: Mime-Version: 1.0 (MHng) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200825_140419_227887_01842E41 X-CRM114-Status: GOOD ( 33.58 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-efi@vger.kernel.org, ardb@kernel.org, Atish Patra , nivedita@alum.mit.edu, Alistair Francis , zong.li@sifive.com, linux-riscv@lists.infradead.org, mingo@kernel.org, anup@brainfault.org, masahiroy@kernel.org, michal.simek@xilinx.com, steven.price@arm.com, longman@redhat.com, greentime.hu@sifive.com, daniel.schaefer@hpe.com, keescook@chromium.org, abner.chang@hpe.com, hca@linux.ibm.com, Paul Walmsley , Damien Le Moal , Anup Patel , Nick Desaulniers , linux-kernel@vger.kernel.org, rppt@kernel.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Wed, 19 Aug 2020 15:24:21 PDT (-0700), Atish Patra wrote: > Linux kernel Image can appear as an EFI application With appropriate > PE/COFF header fields in the beginning of the Image header. An EFI > application loader can directly load a Linux kernel Image and an EFI > stub residing in kernel can boot Linux kernel directly. > > Add the necessary PE/COFF header. > > Signed-off-by: Atish Patra > Link: https://lore.kernel.org/r/20200421033336.9663-3-atish.patra@wdc.com > [ardb: - use C prefix for c.li to ensure the expected opcode is emitted > - align all image sections according to PE/COFF section alignment ] > Signed-off-by: Ard Biesheuvel > Reviewed-by: Anup Patel > --- > arch/riscv/include/asm/sections.h | 13 ++++ > arch/riscv/kernel/Makefile | 4 ++ > arch/riscv/kernel/efi-header.S | 104 ++++++++++++++++++++++++++++++ > arch/riscv/kernel/head.S | 16 +++++ > arch/riscv/kernel/image-vars.h | 51 +++++++++++++++ > arch/riscv/kernel/vmlinux.lds.S | 22 ++++++- > 6 files changed, 208 insertions(+), 2 deletions(-) > create mode 100644 arch/riscv/include/asm/sections.h > create mode 100644 arch/riscv/kernel/efi-header.S > create mode 100644 arch/riscv/kernel/image-vars.h > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h > new file mode 100644 > index 000000000000..3a9971b1210f > --- /dev/null > +++ b/arch/riscv/include/asm/sections.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + */ > +#ifndef __ASM_SECTIONS_H > +#define __ASM_SECTIONS_H > + > +#include > + > +extern char _start[]; > +extern char _start_kernel[]; > + > +#endif /* __ASM_SECTIONS_H */ > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile > index a5287ab9f7f2..eabec4dce50b 100644 > --- a/arch/riscv/kernel/Makefile > +++ b/arch/riscv/kernel/Makefile > @@ -32,6 +32,10 @@ obj-y += patch.o > obj-$(CONFIG_MMU) += vdso.o vdso/ > > obj-$(CONFIG_RISCV_M_MODE) += clint.o traps_misaligned.o > +OBJCOPYFLAGS := --prefix-symbols=__efistub_ > +$(obj)/%.stub.o: $(obj)/%.o FORCE > + $(call if_changed,objcopy) > + Is there a reason this is below those objects? I don't really care, but it triggered a merge conflict and it seems cleaner above so I put it up there. > obj-$(CONFIG_FPU) += fpu.o > obj-$(CONFIG_SMP) += smpboot.o > obj-$(CONFIG_SMP) += smp.o > diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S > new file mode 100644 > index 000000000000..822b4c9ff2bb > --- /dev/null > +++ b/arch/riscv/kernel/efi-header.S > @@ -0,0 +1,104 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * Adapted from arch/arm64/kernel/efi-header.S > + */ > + > +#include > +#include > + > + .macro __EFI_PE_HEADER > + .long PE_MAGIC > +coff_header: > +#ifdef CONFIG_64BIT > + .short IMAGE_FILE_MACHINE_RISCV64 // Machine > +#else > + .short IMAGE_FILE_MACHINE_RISCV32 // Machine > +#endif > + .short section_count // NumberOfSections > + .long 0 // TimeDateStamp > + .long 0 // PointerToSymbolTable > + .long 0 // NumberOfSymbols > + .short section_table - optional_header // SizeOfOptionalHeader > + .short IMAGE_FILE_DEBUG_STRIPPED | \ > + IMAGE_FILE_EXECUTABLE_IMAGE | \ > + IMAGE_FILE_LINE_NUMS_STRIPPED // Characteristics > + > +optional_header: > + .short PE_OPT_MAGIC_PE32PLUS // PE32+ format > + .byte 0x02 // MajorLinkerVersion > + .byte 0x14 // MinorLinkerVersion > + .long __pecoff_text_end - efi_header_end // SizeOfCode > + .long __pecoff_data_virt_size // SizeOfInitializedData > + .long 0 // SizeOfUninitializedData > + .long __efistub_efi_pe_entry - _start // AddressOfEntryPoint > + .long efi_header_end - _start // BaseOfCode > + > +extra_header_fields: > + .quad 0 // ImageBase > + .long PECOFF_SECTION_ALIGNMENT // SectionAlignment > + .long PECOFF_FILE_ALIGNMENT // FileAlignment > + .short 0 // MajorOperatingSystemVersion > + .short 0 // MinorOperatingSystemVersion > + .short LINUX_EFISTUB_MAJOR_VERSION // MajorImageVersion > + .short LINUX_EFISTUB_MINOR_VERSION // MinorImageVersion > + .short 0 // MajorSubsystemVersion > + .short 0 // MinorSubsystemVersion > + .long 0 // Win32VersionValue > + > + .long _end - _start // SizeOfImage > + > + // Everything before the kernel image is considered part of the header > + .long efi_header_end - _start // SizeOfHeaders > + .long 0 // CheckSum > + .short IMAGE_SUBSYSTEM_EFI_APPLICATION // Subsystem > + .short 0 // DllCharacteristics > + .quad 0 // SizeOfStackReserve > + .quad 0 // SizeOfStackCommit > + .quad 0 // SizeOfHeapReserve > + .quad 0 // SizeOfHeapCommit > + .long 0 // LoaderFlags > + .long (section_table - .) / 8 // NumberOfRvaAndSizes > + > + .quad 0 // ExportTable > + .quad 0 // ImportTable > + .quad 0 // ResourceTable > + .quad 0 // ExceptionTable > + .quad 0 // CertificationTable > + .quad 0 // BaseRelocationTable > + > + // Section table > +section_table: > + .ascii ".text\0\0\0" > + .long __pecoff_text_end - efi_header_end // VirtualSize > + .long efi_header_end - _start // VirtualAddress > + .long __pecoff_text_end - efi_header_end // SizeOfRawData > + .long efi_header_end - _start // PointerToRawData > + > + .long 0 // PointerToRelocations > + .long 0 // PointerToLineNumbers > + .short 0 // NumberOfRelocations > + .short 0 // NumberOfLineNumbers > + .long IMAGE_SCN_CNT_CODE | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_EXECUTE // Characteristics > + > + .ascii ".data\0\0\0" > + .long __pecoff_data_virt_size // VirtualSize > + .long __pecoff_text_end - _start // VirtualAddress > + .long __pecoff_data_raw_size // SizeOfRawData > + .long __pecoff_text_end - _start // PointerToRawData > + > + .long 0 // PointerToRelocations > + .long 0 // PointerToLineNumbers > + .short 0 // NumberOfRelocations > + .short 0 // NumberOfLineNumbers > + .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ > + IMAGE_SCN_MEM_READ | \ > + IMAGE_SCN_MEM_WRITE // Characteristics > + > + .set section_count, (. - section_table) / 40 > + > + .balign 0x1000 > +efi_header_end: > + .endm > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > index c6a37e8231a8..3631147732ee 100644 > --- a/arch/riscv/kernel/head.S > +++ b/arch/riscv/kernel/head.S > @@ -13,6 +13,7 @@ > #include > #include > #include > +#include "efi-header.S" > > __HEAD > ENTRY(_start) > @@ -22,10 +23,18 @@ ENTRY(_start) > * Do not modify it without modifying the structure and all bootloaders > * that expects this header format!! > */ > +#ifdef CONFIG_EFI > + /* > + * This instruction decodes to "MZ" ASCII required by UEFI. > + */ > + c.li s4,-13 > + j _start_kernel > +#else > /* jump to start kernel */ > j _start_kernel > /* reserved */ > .word 0 > +#endif > .balign 8 > #if __riscv_xlen == 64 > /* Image load offset(2MB) from start of RAM */ > @@ -43,7 +52,14 @@ ENTRY(_start) > .ascii RISCV_IMAGE_MAGIC > .balign 4 > .ascii RISCV_IMAGE_MAGIC2 > +#ifdef CONFIG_EFI > + .word pe_head_start - _start > +pe_head_start: > + > + __EFI_PE_HEADER > +#else > .word 0 > +#endif > > .align 2 > #ifdef CONFIG_MMU > diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h > new file mode 100644 > index 000000000000..8c212efb37a6 > --- /dev/null > +++ b/arch/riscv/kernel/image-vars.h > @@ -0,0 +1,51 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Western Digital Corporation or its affiliates. > + * Linker script variables to be set after section resolution, as > + * ld.lld does not like variables assigned before SECTIONS is processed. > + * Based on arch/arm64/kerne/image-vars.h > + */ > +#ifndef __RISCV_KERNEL_IMAGE_VARS_H > +#define __RISCV_KERNEL_IMAGE_VARS_H > + > +#ifndef LINKER_SCRIPT > +#error This file should only be included in vmlinux.lds.S > +#endif > + > +#ifdef CONFIG_EFI > + > +/* > + * The EFI stub has its own symbol namespace prefixed by __efistub_, to > + * isolate it from the kernel proper. The following symbols are legally > + * accessed by the stub, so provide some aliases to make them accessible. > + * Only include data symbols here, or text symbols of functions that are > + * guaranteed to be safe when executed at another offset than they were > + * linked at. The routines below are all implemented in assembler in a > + * position independent manner > + */ > +__efistub_memcmp = memcmp; > +__efistub_memchr = memchr; > +__efistub_memcpy = memcpy; > +__efistub_memmove = memmove; > +__efistub_memset = memset; > +__efistub_strlen = strlen; > +__efistub_strnlen = strnlen; > +__efistub_strcmp = strcmp; > +__efistub_strncmp = strncmp; > +__efistub_strrchr = strrchr; > + > +#ifdef CONFIG_KASAN > +__efistub___memcpy = memcpy; > +__efistub___memmove = memmove; > +__efistub___memset = memset; > +#endif > + > +__efistub__start = _start; > +__efistub__start_kernel = _start_kernel; > +__efistub__end = _end; > +__efistub__edata = _edata; > +__efistub_screen_info = screen_info; > + > +#endif > + > +#endif /* __RISCV_KERNEL_IMAGE_VARS_H */ > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > index f3586e31ed1e..6dcf790282dd 100644 > --- a/arch/riscv/kernel/vmlinux.lds.S > +++ b/arch/riscv/kernel/vmlinux.lds.S > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include "image-vars.h" > > #include > OUTPUT_ARCH(riscv) > @@ -17,6 +18,9 @@ ENTRY(_start) > > jiffies = jiffies_64; > > +PECOFF_SECTION_ALIGNMENT = 0x1000; > +PECOFF_FILE_ALIGNMENT = 0x200; > + > SECTIONS > { > /* Beginning of code and text segment */ > @@ -76,6 +80,10 @@ SECTIONS > > EXCEPTION_TABLE(0x10) > > +#ifdef CONFIG_EFI > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > + __pecoff_text_end = .; > +#endif > . = ALIGN(SECTION_ALIGN); > _data = .; > > @@ -83,16 +91,26 @@ SECTIONS > .sdata : { > __global_pointer$ = . + 0x800; > *(.sdata*) > - /* End of data section */ > - _edata = .; > } > > +#ifdef CONFIG_EFI > + .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); } > + __pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end); > +#endif > + > + /* End of data section */ > + _edata = .; > + > BSS_SECTION(PAGE_SIZE, PAGE_SIZE, 0) > > .rel.dyn : { > *(.rel.dyn*) > } > > +#ifdef CONFIG_EFI > + . = ALIGN(PECOFF_SECTION_ALIGNMENT); > + __pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end); > +#endif > _end = .; > > STABS_DEBUG _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv