From patchwork Thu Mar 24 20:00:31 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Konrad Rzeszutek Wilk X-Patchwork-Id: 8664261 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id CCE2BC0553 for ; Thu, 24 Mar 2016 20:03:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E239820380 for ; Thu, 24 Mar 2016 20:03:40 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 190482037E for ; Thu, 24 Mar 2016 20:03:39 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ajBRZ-0007Re-FR; Thu, 24 Mar 2016 20:01:21 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ajBRY-0007PW-GP for xen-devel@lists.xenproject.org; Thu, 24 Mar 2016 20:01:20 +0000 Received: from [85.158.137.68] by server-5.bemta-3.messagelabs.com id C8/80-03651-F8744F65; Thu, 24 Mar 2016 20:01:19 +0000 X-Env-Sender: konrad@char.us.oracle.com X-Msg-Ref: server-3.tower-31.messagelabs.com!1458849677!31285431!1 X-Originating-IP: [141.146.126.69] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTQxLjE0Ni4xMjYuNjkgPT4gMjc3MjE4\n X-StarScan-Received: X-StarScan-Version: 8.11; banners=-,-,- X-VirusChecked: Checked Received: (qmail 45868 invoked from network); 24 Mar 2016 20:01:18 -0000 Received: from aserp1040.oracle.com (HELO aserp1040.oracle.com) (141.146.126.69) by server-3.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 24 Mar 2016 20:01:18 -0000 Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id u2OK17G0015290 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 24 Mar 2016 20:01:07 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserv0021.oracle.com (8.13.8/8.13.8) with ESMTP id u2OK17r1013826 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 24 Mar 2016 20:01:07 GMT Received: from abhmp0015.oracle.com (abhmp0015.oracle.com [141.146.116.21]) by aserv0121.oracle.com (8.13.8/8.13.8) with ESMTP id u2OK176m014990; Thu, 24 Mar 2016 20:01:07 GMT Received: from char.us.oracle.com (/10.137.176.158) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 24 Mar 2016 13:01:06 -0700 Received: by char.us.oracle.com (Postfix, from userid 1000) id E4C1E6A00E9; Thu, 24 Mar 2016 16:01:03 -0400 (EDT) From: Konrad Rzeszutek Wilk To: xen-devel@lists.xenproject.org, ross.lagerwall@citrix.com, konrad@kernel.org, andrew.cooper3@citrix.com, mpohlack@amazon.de, sasha.levin@oracle.com Date: Thu, 24 Mar 2016 16:00:31 -0400 Message-Id: <1458849640-22588-20-git-send-email-konrad.wilk@oracle.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1458849640-22588-1-git-send-email-konrad.wilk@oracle.com> References: <1458849640-22588-1-git-send-email-konrad.wilk@oracle.com> X-Source-IP: aserv0021.oracle.com [141.146.126.233] Cc: Keir Fraser , Julien Grall , Stefano Stabellini , Jan Beulich , Konrad Rzeszutek Wilk Subject: [Xen-devel] [PATCH v5 19/28] build_id: Provide ld-embedded build-ids X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch enables the Elf to be built with the build-id and provide in the Xen hypervisor the code to extract it. One can also retrieve the value of the build-id by doing 'readelf -n xen-syms'. For EFI builds we re-use the same build-id that the xen-syms was built with. The version of ld that first implemented --build-id is v2.18. Hence we check for that or later version - if older version found we do not build the hypervisor with the build-id (and the return code is -ENODATA for xen_build_id() call). For x86 we have two binaries - the xen-syms and the xen - an smaller version with lots of sections removed. To make it possible for readelf -n xen we also modify mkelf32 and xen.lds.S to include the PT_NOTE ELF section. The EFI binary is more complicated. Having any non-recognizable sections (.note, .data.note, etc) causes the boot to hang. Moving the .note in the .data section makes it work. It is also worth noting that the PE/COFF does not have any "comment" sections to the author. Lastly, we MUST call --binary-id=sha1 on all linker invocation so that symbol offsets don't changes (which means we have multiple binary ids - except that the last one is the final one). Without this change, the symbol table embedded in Xen are incorrect - some of the values it contains are offset by the size of the included build id. This obviously causes problems when resolving symbols. Suggested-by: Andrew Cooper Signed-off-by: Martin Pohlack Signed-off-by: Konrad Rzeszutek Wilk --- Cc: Stefano Stabellini Cc: Julien Grall Cc: Keir Fraser Cc: Jan Beulich Cc: Andrew Cooper v1: Rebase it on Martin's initial patch v2: Move it to XENVER hypercall v3: Fix EFI building (Ross's fix) Don't use the third argument for length. Use new structure for XENVER_build_id with variable buf. Include Ross's fix. Include detection of bin-utils for build-id support, add probing for size, and return -EPERM for XSM denied calls. Build xen_build_id under ARM, required adding ELFSIZE in proper file. Rebase on top XSM version class. v4: Include the build-id .note in the xen ELF binary. s/build_id/build_id_linker/ For EFI build, moved the --build-id values in .data section Rebase on staging. Split patch in two. Always do --build-id call. Include the .note in .rodata. USe const void * and ssize_t Use -S to make build_id.o and objcopy differently (Andrew suggested) v5: Put back the #ifdef LOCK_PROFILE on ARM. (Bad change). Move the _erodata around. s/ssize_t/unsigned int/ --- Config.mk | 11 ++++ xen/arch/arm/Makefile | 2 +- xen/arch/arm/xen.lds.S | 14 ++++- xen/arch/x86/Makefile | 30 ++++++++-- xen/arch/x86/boot/mkelf32.c | 137 ++++++++++++++++++++++++++++++++++++++------ xen/arch/x86/xen.lds.S | 23 ++++++++ xen/common/version.c | 51 +++++++++++++++++ xen/include/xen/version.h | 3 + 8 files changed, 248 insertions(+), 23 deletions(-) diff --git a/Config.mk b/Config.mk index 79eb2bd..c8e89fe 100644 --- a/Config.mk +++ b/Config.mk @@ -126,6 +126,17 @@ endef check-$(gcc) = $(call cc-ver-check,CC,0x040100,"Xen requires at least gcc-4.1") $(eval $(check-y)) +ld-ver-build-id = $(shell $(1) --build-id 2>&1 | \ + grep -q unrecognized && echo n || echo y) + +# binutils 2.18 implement build-id. +ifeq ($(call ld-ver-build-id,$(LD)),n) +build_id_linker := +else +CFLAGS += -DBUILD_ID +build_id_linker := --build-id=sha1 +endif + # as-insn: Check whether assembler supports an instruction. # Usage: cflags-y += $(call as-insn "insn",option-yes,option-no) as-insn = $(if $(shell echo 'void _(void) { asm volatile ( $(2) ); }' \ diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile index 17e9e3a..a3319ab 100644 --- a/xen/arch/arm/Makefile +++ b/xen/arch/arm/Makefile @@ -94,7 +94,7 @@ $(TARGET)-syms: prelink.o xen.lds $(BASEDIR)/common/symbols-dummy.o $(NM) -pa --format=sysv $(@D)/.$(@F).1 \ | $(BASEDIR)/tools/symbols --sysv --sort >$(@D)/.$(@F).1.S $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o - $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \ + $(LD) $(LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \ $(@D)/.$(@F).1.o -o $@ rm -f $(@D)/.$(@F).[0-9]* diff --git a/xen/arch/arm/xen.lds.S b/xen/arch/arm/xen.lds.S index 9909595..aad26e3 100644 --- a/xen/arch/arm/xen.lds.S +++ b/xen/arch/arm/xen.lds.S @@ -22,6 +22,9 @@ OUTPUT_ARCH(FORMAT) PHDRS { text PT_LOAD /* XXX should be AT ( XEN_PHYS_START ) */ ; +#if defined(BUILD_ID) + note PT_NOTE ; +#endif } SECTIONS { @@ -57,9 +60,18 @@ SECTIONS *(.lockprofile.data) __lock_profile_end = .; #endif + } :text - _erodata = .; /* End of read-only data */ +#if defined(BUILD_ID) + .note : { + __note_gnu_build_id_start = .; + *(.note.gnu.build-id) + __note_gnu_build_id_end = .; + *(.note) + *(.note.*) } :text +#endif + _erodata = .; /* End of read-only data */ .data : { /* Data */ . = ALIGN(PAGE_SIZE); diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile index d4a8069..7a1f710 100644 --- a/xen/arch/x86/Makefile +++ b/xen/arch/x86/Makefile @@ -72,9 +72,16 @@ efi-y := $(shell if [ ! -r $(BASEDIR)/include/xen/compile.h -o \ -O $(BASEDIR)/include/xen/compile.h ]; then \ echo '$(TARGET).efi'; fi) +ifdef build_id_linker +num_phdrs = 2 +else +num_phdrs = 1 +endif + $(TARGET): $(TARGET)-syms $(efi-y) boot/mkelf32 ./boot/mkelf32 $(TARGET)-syms $(TARGET) 0x100000 \ - `$(NM) -nr $(TARGET)-syms | head -n 1 | sed -e 's/^\([^ ]*\).*/0x\1/'` + `$(NM) -nr $(TARGET)-syms | head -n 1 | sed -e 's/^\([^ ]*\).*/0x\1/'` \ + $(num_phdrs) $(MAKE) -f $(BASEDIR)/Rules.mk -C test install: @@ -110,22 +117,28 @@ $(BASEDIR)/common/symbols-dummy.o: $(MAKE) -f $(BASEDIR)/Rules.mk -C $(BASEDIR)/common symbols-dummy.o $(TARGET)-syms: prelink.o xen.lds $(BASEDIR)/common/symbols-dummy.o - $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \ + $(LD) $(LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \ $(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0 $(NM) -pa --format=sysv $(@D)/.$(@F).0 \ | $(BASEDIR)/tools/symbols --all-symbols --sysv --sort \ >$(@D)/.$(@F).0.S $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o - $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \ + $(LD) $(LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \ $(@D)/.$(@F).0.o -o $(@D)/.$(@F).1 $(NM) -pa --format=sysv $(@D)/.$(@F).1 \ | $(BASEDIR)/tools/symbols --all-symbols --sysv --sort --warn-dup \ >$(@D)/.$(@F).1.S $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o - $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \ + $(LD) $(LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \ $(@D)/.$(@F).1.o -o $@ rm -f $(@D)/.$(@F).[0-9]* +build_id.o: $(TARGET)-syms + $(OBJCOPY) -O binary --only-section=.note $(BASEDIR)/xen-syms $@.bin + $(OBJCOPY) -I binary -O elf64-x86-64 -B i386:x86-64 \ + --rename-section=.data=.note.gnu.build-id -S $@.bin $@ + rm -f $@.bin + EFI_LDFLAGS = $(patsubst -m%,-mi386pep,$(LDFLAGS)) --subsystem=10 EFI_LDFLAGS += --image-base=$(1) --stack=0,0 --heap=0,0 --strip-debug EFI_LDFLAGS += --section-alignment=0x200000 --file-alignment=0x20 @@ -138,6 +151,13 @@ $(TARGET).efi: VIRT_BASE = 0x$(shell $(NM) efi/relocs-dummy.o | sed -n 's, A VIR $(TARGET).efi: ALT_BASE = 0x$(shell $(NM) efi/relocs-dummy.o | sed -n 's, A ALT_START$$,,p') # Don't use $(wildcard ...) here - at least make 3.80 expands this too early! $(TARGET).efi: guard = $(if $(shell echo efi/dis* | grep disabled),:) +ifdef build_id_linker +$(TARGET).efi: build_id.o +build_id_file := build_id.o +else +build_id_file := +endif + $(TARGET).efi: prelink-efi.o efi.lds efi/relocs-dummy.o $(BASEDIR)/common/symbols-dummy.o efi/mkreloc $(foreach base, $(VIRT_BASE) $(ALT_BASE), \ $(guard) $(LD) $(call EFI_LDFLAGS,$(base)) -T efi.lds -N $< efi/relocs-dummy.o \ @@ -154,7 +174,7 @@ $(TARGET).efi: prelink-efi.o efi.lds efi/relocs-dummy.o $(BASEDIR)/common/symbol | $(guard) $(BASEDIR)/tools/symbols --sysv --sort >$(@D)/.$(@F).1s.S $(guard) $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1r.o $(@D)/.$(@F).1s.o $(guard) $(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T efi.lds -N $< \ - $(@D)/.$(@F).1r.o $(@D)/.$(@F).1s.o -o $@ + $(@D)/.$(@F).1r.o $(@D)/.$(@F).1s.o $(build_id_file) -o $@ if $(guard) false; then rm -f $@; echo 'EFI support disabled'; fi rm -f $(@D)/.$(@F).[0-9]* diff --git a/xen/arch/x86/boot/mkelf32.c b/xen/arch/x86/boot/mkelf32.c index 993a7ee..d230e4c 100644 --- a/xen/arch/x86/boot/mkelf32.c +++ b/xen/arch/x86/boot/mkelf32.c @@ -45,9 +45,9 @@ static Elf32_Ehdr out_ehdr = { 0, /* e_flags */ sizeof(Elf32_Ehdr), /* e_ehsize */ sizeof(Elf32_Phdr), /* e_phentsize */ - 1, /* e_phnum */ + 1, /* modify based on num_phdrs */ /* e_phnum */ sizeof(Elf32_Shdr), /* e_shentsize */ - 3, /* e_shnum */ + 3, /* modify based on num_phdrs */ /* e_shnum */ 2 /* e_shstrndx */ }; @@ -61,8 +61,20 @@ static Elf32_Phdr out_phdr = { PF_R|PF_W|PF_X, /* p_flags */ 64 /* p_align */ }; +static Elf32_Phdr note_phdr = { + PT_NOTE, /* p_type */ + DYNAMICALLY_FILLED, /* p_offset */ + DYNAMICALLY_FILLED, /* p_vaddr */ + DYNAMICALLY_FILLED, /* p_paddr */ + DYNAMICALLY_FILLED, /* p_filesz */ + DYNAMICALLY_FILLED, /* p_memsz */ + PF_R, /* p_flags */ + 4 /* p_align */ +}; static u8 out_shstrtab[] = "\0.text\0.shstrtab"; +/* If num_phdrs >= 2, we need to tack the .note. */ +static u8 out_shstrtab_extra[] = ".note\0"; static Elf32_Shdr out_shdr[] = { { 0 }, @@ -90,6 +102,23 @@ static Elf32_Shdr out_shdr[] = { } }; +/* + * The 17 points to the '.note' in the out_shstrtab and out_shstrtab_extra + * laid out in the file. + */ +static Elf32_Shdr out_shdr_extra = { + 17, /* sh_name */ + SHT_NOTE, /* sh_type */ + 0, /* sh_flags */ + DYNAMICALLY_FILLED, /* sh_addr */ + DYNAMICALLY_FILLED, /* sh_offset */ + DYNAMICALLY_FILLED, /* sh_size */ + 0, /* sh_link */ + 0, /* sh_info */ + 4, /* sh_addralign */ + 0 /* sh_entsize */ +}; + /* Some system header files define these macros and pollute our namespace. */ #undef swap16 #undef swap32 @@ -228,21 +257,22 @@ static void do_read(int fd, void *data, int len) int main(int argc, char **argv) { u64 final_exec_addr; - u32 loadbase, dat_siz, mem_siz; + u32 loadbase, dat_siz, mem_siz, note_base, note_sz, offset; char *inimage, *outimage; int infd, outfd; char buffer[1024]; int bytes, todo, i; + int num_phdrs; Elf32_Ehdr in32_ehdr; Elf64_Ehdr in64_ehdr; Elf64_Phdr in64_phdr; - if ( argc != 5 ) + if ( argc != 6 ) { fprintf(stderr, "Usage: mkelf32 " - " \n"); + " \n"); return 1; } @@ -250,7 +280,13 @@ int main(int argc, char **argv) outimage = argv[2]; loadbase = strtoul(argv[3], NULL, 16); final_exec_addr = strtoull(argv[4], NULL, 16); - + num_phdrs = atoi(argv[5]); + if ( num_phdrs > 2 || num_phdrs < 1 ) + { + fprintf(stderr, "Number of program headers MUST be 1 or 2, got %d!\n", + num_phdrs); + return 1; + } infd = open(inimage, O_RDONLY); if ( infd == -1 ) { @@ -285,11 +321,10 @@ int main(int argc, char **argv) (int)in64_ehdr.e_phentsize, (int)sizeof(in64_phdr)); return 1; } - - if ( in64_ehdr.e_phnum != 1 ) + if ( in64_ehdr.e_phnum != num_phdrs ) { - fprintf(stderr, "Expect precisly 1 program header; found %d.\n", - (int)in64_ehdr.e_phnum); + fprintf(stderr, "Expect precisly %d program header; found %d.\n", + num_phdrs, (int)in64_ehdr.e_phnum); return 1; } @@ -299,11 +334,36 @@ int main(int argc, char **argv) (void)lseek(infd, in64_phdr.p_offset, SEEK_SET); dat_siz = (u32)in64_phdr.p_filesz; - /* Do not use p_memsz: it does not include BSS alignment padding. */ /*mem_siz = (u32)in64_phdr.p_memsz;*/ mem_siz = (u32)(final_exec_addr - in64_phdr.p_vaddr); + note_sz = note_base = offset = 0; + if ( num_phdrs > 1 ) + { + offset = in64_phdr.p_offset; + note_base = in64_phdr.p_vaddr; + + (void)lseek(infd, in64_ehdr.e_phoff+sizeof(in64_phdr), SEEK_SET); + do_read(infd, &in64_phdr, sizeof(in64_phdr)); + endianadjust_phdr64(&in64_phdr); + + (void)lseek(infd, offset, SEEK_SET); + + note_sz = in64_phdr.p_memsz; + note_base = in64_phdr.p_vaddr - note_base; + + if ( in64_phdr.p_offset > dat_siz || offset > in64_phdr.p_offset ) + { + fprintf(stderr, "Expected .note section within .text section!\n" \ + "Offset %ld not within %d!\n", + in64_phdr.p_offset, dat_siz); + return 1; + } + /* Gets us the absolute offset within the .text section. */ + offset = in64_phdr.p_offset - offset; + } + /* * End the image on a page boundary. This gets round alignment bugs * in the boot- or chain-loader (e.g., kexec on the XenoBoot CD). @@ -322,6 +382,31 @@ int main(int argc, char **argv) out_shdr[1].sh_size = dat_siz; out_shdr[2].sh_offset = RAW_OFFSET + dat_siz + sizeof(out_shdr); + if ( num_phdrs > 1 ) + { + /* We have two of them! */ + out_ehdr.e_phnum = num_phdrs; + /* Extra .note section. */ + out_ehdr.e_shnum++; + + /* Fill out the PT_NOTE program header. */ + note_phdr.p_vaddr = note_base; + note_phdr.p_paddr = note_base; + note_phdr.p_filesz = note_sz; + note_phdr.p_memsz = note_sz; + note_phdr.p_offset = offset; + + /* Tack on the .note\0 */ + out_shdr[2].sh_size += sizeof(out_shstrtab_extra); + /* And move it past the .note section. */ + out_shdr[2].sh_offset += sizeof(out_shdr_extra); + + /* Fill out the .note section. */ + out_shdr_extra.sh_size = note_sz; + out_shdr_extra.sh_addr = note_base; + out_shdr_extra.sh_offset = RAW_OFFSET + offset; + } + outfd = open(outimage, O_WRONLY|O_CREAT|O_TRUNC, 0775); if ( outfd == -1 ) { @@ -335,8 +420,15 @@ int main(int argc, char **argv) endianadjust_phdr32(&out_phdr); do_write(outfd, &out_phdr, sizeof(out_phdr)); - - if ( (bytes = RAW_OFFSET - sizeof(out_ehdr) - sizeof(out_phdr)) < 0 ) + + if ( num_phdrs > 1 ) + { + endianadjust_phdr32(¬e_phdr); + do_write(outfd, ¬e_phdr, sizeof(note_phdr)); + } + + if ( (bytes = RAW_OFFSET - sizeof(out_ehdr) - sizeof(out_phdr) - + ( num_phdrs > 1 ? sizeof(note_phdr) : 0 ) ) < 0 ) { fprintf(stderr, "Header overflow.\n"); return 1; @@ -355,9 +447,22 @@ int main(int argc, char **argv) endianadjust_shdr32(&out_shdr[i]); do_write(outfd, &out_shdr[0], sizeof(out_shdr)); - do_write(outfd, out_shstrtab, sizeof(out_shstrtab)); - do_write(outfd, buffer, 4-((sizeof(out_shstrtab)+dat_siz)&3)); - + if ( num_phdrs > 1 ) + { + endianadjust_shdr32(&out_shdr_extra); + /* Append the .note section. */ + do_write(outfd, &out_shdr_extra, sizeof(out_shdr_extra)); + /* The normal strings - .text\0.. */ + do_write(outfd, out_shstrtab, sizeof(out_shstrtab)); + /* Our .note */ + do_write(outfd, out_shstrtab_extra, sizeof(out_shstrtab_extra)); + do_write(outfd, buffer, 4-((sizeof(out_shstrtab)+sizeof(out_shstrtab_extra)+dat_siz)&3)); + } + else + { + do_write(outfd, out_shstrtab, sizeof(out_shstrtab)); + do_write(outfd, buffer, 4-((sizeof(out_shstrtab)+dat_siz)&3)); + } close(infd); close(outfd); diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S index 5eb825e..d8661e3 100644 --- a/xen/arch/x86/xen.lds.S +++ b/xen/arch/x86/xen.lds.S @@ -31,6 +31,9 @@ OUTPUT_ARCH(i386:x86-64) PHDRS { text PT_LOAD ; +#if defined(BUILD_ID) && !defined(EFI) + note PT_NOTE ; +#endif } SECTIONS { @@ -78,6 +81,11 @@ SECTIONS *(.rodata) *(.rodata.*) +#if defined(BUILD_ID) && defined(EFI) + __note_gnu_build_id_start = .; + *(.note.gnu.build-id) + __note_gnu_build_id_end = .; +#endif . = ALIGN(8); /* Exception table */ @@ -99,6 +107,21 @@ SECTIONS _erodata = .; } :text +#if defined(BUILD_ID) && !defined(EFI) +/* + * No mechanism to put an PT_NOTE in the EFI file - so put + * it in .data section. + */ + . = ALIGN(4); + .note : { + __note_gnu_build_id_start = .; + *(.note.gnu.build-id) + __note_gnu_build_id_end = .; + *(.note) + *(.note.*) + } :note :text +#endif + #ifdef EFI . = ALIGN(MB(2)); #else diff --git a/xen/common/version.c b/xen/common/version.c index fc9bf42..35078c7 100644 --- a/xen/common/version.c +++ b/xen/common/version.c @@ -1,5 +1,9 @@ #include +#include +#include +#include #include +#include const char *xen_compile_date(void) { @@ -61,6 +65,53 @@ const char *xen_deny(void) return ""; } +#ifdef BUILD_ID +#define NT_GNU_BUILD_ID 3 +/* Defined in linker script. */ +extern const Elf_Note __note_gnu_build_id_start[], __note_gnu_build_id_end[]; + +int xen_build_id(const void **p, unsigned int *len) +{ + const Elf_Note *n = __note_gnu_build_id_start; + static bool_t checked = 0; + + if ( checked ) + { + *len = n->descsz; + *p = ELFNOTE_DESC(n); + return 0; + } + /* --build-id invoked with wrong parameters. */ + if ( __note_gnu_build_id_end <= __note_gnu_build_id_start ) + return -ENODATA; + + /* Check for full Note header. */ + if ( &n[1] > __note_gnu_build_id_end ) + return -ENODATA; + + /* Check if we really have a build-id. */ + if ( NT_GNU_BUILD_ID != n->type ) + return -ENODATA; + + /* Sanity check, name should be "GNU" for ld-generated build-id. */ + if ( strncmp(ELFNOTE_NAME(n), "GNU", n->namesz) != 0 ) + return -ENODATA; + + *len = n->descsz; + *p = ELFNOTE_DESC(n); + + checked = 1; + return 0; +} + +#else + +int xen_build_id(const void **p, unsigned int *len) +{ + return -ENODATA; +} +#endif + /* * Local variables: * mode: C diff --git a/xen/include/xen/version.h b/xen/include/xen/version.h index 2015c0b..4b57e18 100644 --- a/xen/include/xen/version.h +++ b/xen/include/xen/version.h @@ -14,4 +14,7 @@ const char *xen_changeset(void); const char *xen_banner(void); const char *xen_deny(void); +#include +int xen_build_id(const void **p, unsigned int *len); + #endif /* __XEN_VERSION_H__ */