From a2037dba7e8671c533ede60b8fdb3f09c03b565d Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Wed, 4 Mar 2020 21:01:22 +0000 Subject: [PATCH] Link stand/i386 components using a linker script LLD 10.0.0 changed the behavior of the -Ttext option, so that using -Ttext=0x0 now causes linking of the loaders to fail with: ld: error: output file too large: 18446744073707016908 bytes I reported this in https://bugs.llvm.org/show_bug.cgi?id=44715, and initially reverted the upstream change in r357259 to work around it. However, after some discussion with Fangrui Song in the upstream ticket, I think we can classify this as an unfortunate interaction between using -Ttext=0 in combination with --no-rosegment. (We added the latter in r332090, because btxld does not correctly handle input with more than 2 PT_LOAD segments.) Fangrui suggested to use a linker script instead, and Warner was already attempting this in r305353, but had to revert it due to "crypto-using boot problems" (not sure what those were :). This review updates the stand/i386/boot.ldscript to handle more sections, inserts some symbols like _edata and such that we use in libsa, and also discards any .interp section. It uses ORG which is defined on the linker command line using --defsym ORG=value to set the start of all the sections. Reviewed by: imp MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D23952 --- stand/i386/Makefile.inc | 9 ++++----- stand/i386/boot.ldscript | 16 +++++++++++----- stand/i386/boot2/Makefile | 4 ++-- stand/i386/gptboot/Makefile | 4 ++-- stand/i386/gptzfsboot/Makefile | 4 ++-- stand/i386/isoboot/Makefile | 4 ++-- stand/i386/loader/Makefile | 4 +++- stand/i386/zfsboot/Makefile | 4 ++-- 8 files changed, 28 insertions(+), 21 deletions(-) diff --git a/stand/i386/Makefile.inc b/stand/i386/Makefile.inc index e2723dd79cdb..119f8a37162f 100644 --- a/stand/i386/Makefile.inc +++ b/stand/i386/Makefile.inc @@ -22,13 +22,12 @@ CFLAGS+= -I${BTXLIB} # compact binary with no padding between text, data, bss LDSCRIPT= ${BOOTSRC}/i386/boot.ldscript -# LDFLAGS_BIN=-e start -Ttext ${ORG} -Wl,-T,${LDSCRIPT},-S,--oformat,binary -# LD_FLAGS_BIN=-static -T ${LDSCRIPT} --gc-sections -LDFLAGS_BIN=-e start -Ttext ${ORG} -Wl,-N,-S,--oformat,binary +LDFLAGS_ORG= -Wl,--defsym,ORG=${ORG},-T,${LDSCRIPT} +LDFLAGS_BIN= -e start ${LDFLAGS_ORG} -Wl,-N,-S,--oformat,binary .if ${LINKER_FEATURES:Mbuild-id} != "" -LDFLAGS_BIN+=-Wl,--build-id=none +LDFLAGS_BIN+= -Wl,--build-id=none .endif -LD_FLAGS_BIN=-static -N --gc-sections +LD_FLAGS_BIN= -static -N --gc-sections .if ${MACHINE_CPUARCH} == "amd64" DO32=1 diff --git a/stand/i386/boot.ldscript b/stand/i386/boot.ldscript index 04ea39d47693..2f2a2d3e936e 100644 --- a/stand/i386/boot.ldscript +++ b/stand/i386/boot.ldscript @@ -1,11 +1,17 @@ /* $FreeBSD$ */ -/* Merge text, data and bss together almost no padding */ +/* Simplified linker script for the boot loaders. */ OUTPUT_FORMAT("elf32-i386-freebsd") OUTPUT_ARCH(i386) ENTRY(_start) SECTIONS { - . = 0x08048000 + SIZEOF_HEADERS; - .text : { *(.text) } =0x90909090 /* Pad with nops, if needed */ - .data : { *(.data) } _edata = .; - .bss : { *(.bss) } _end = .; + . = ORG; + .text : { *(.text .text.*) } =0xcccccccc /* Pad with int3, if needed */ + .rodata : { *(.rodata .rodata.*) } + .got : { *(.got) *(.igot) } + .got.plt : { *(.got.plt) *(.igot.plt) } + .data : { *(.data .data.*) } + _edata = .; PROVIDE (edata = .); + .bss : { *(.bss .bss.*) } + _end = .; PROVIDE (end = .); + /DISCARD/ : { *(.interp) } } diff --git a/stand/i386/boot2/Makefile b/stand/i386/boot2/Makefile index 73869062204a..3830199b2c4b 100644 --- a/stand/i386/boot2/Makefile +++ b/stand/i386/boot2/Makefile @@ -56,7 +56,7 @@ boot1: boot1.out ${OBJCOPY} -S -O binary boot1.out ${.TARGET} boot1.out: boot1.o - ${LD} ${LD_FLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} boot1.o + ${LD} ${LD_FLAGS} -e start --defsym ORG=${ORG1} -T ${LDSCRIPT} -o ${.TARGET} boot1.o CLEANFILES+= boot2 boot2.ld boot2.ldr boot2.bin boot2.out boot2.o \ boot2.h sio.o @@ -84,7 +84,7 @@ CFLAGS.ashldi3.c= -Wno-missing-prototypes -Wno-missing-declarations CLEANFILES+= ashldi3.o boot2.out: ${BTXCRT} boot2.o sio.o ashldi3.o - ${LD} ${LD_FLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} + ${LD} ${LD_FLAGS} --defsym ORG=${ORG2} -T ${LDSCRIPT} -o ${.TARGET} ${.ALLSRC} SRCS= boot2.c boot2.h diff --git a/stand/i386/gptboot/Makefile b/stand/i386/gptboot/Makefile index 9666c7ab9d99..5ca6ca96535f 100644 --- a/stand/i386/gptboot/Makefile +++ b/stand/i386/gptboot/Makefile @@ -51,7 +51,7 @@ gptldr.bin: gptldr.out ${OBJCOPY} -S -O binary gptldr.out ${.TARGET} gptldr.out: gptldr.o - ${LD} ${LD_FLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} gptldr.o + ${LD} ${LD_FLAGS} -e start --defsym ORG=${ORG1} -T ${LDSCRIPT} -o ${.TARGET} gptldr.o CLEANFILES+= gptboot.bin gptboot.out gptboot.o sio.o drv.o \ cons.o ${OPENCRYPTO_XTS} @@ -60,6 +60,6 @@ gptboot.bin: gptboot.out ${OBJCOPY} -S -O binary gptboot.out ${.TARGET} gptboot.out: ${BTXCRT} gptboot.o sio.o drv.o cons.o ${OPENCRYPTO_XTS} - ${LD} ${LD_FLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} + ${LD} ${LD_FLAGS} --defsym ORG=${ORG2} -T ${LDSCRIPT} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} .include diff --git a/stand/i386/gptzfsboot/Makefile b/stand/i386/gptzfsboot/Makefile index b8b05978b1bd..ecb24e10c6d4 100644 --- a/stand/i386/gptzfsboot/Makefile +++ b/stand/i386/gptzfsboot/Makefile @@ -57,7 +57,7 @@ gptldr.bin: gptldr.out ${OBJCOPY} -S -O binary gptldr.out ${.TARGET} gptldr.out: gptldr.o - ${LD} ${LD_FLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} gptldr.o + ${LD} ${LD_FLAGS} -e start --defsym ORG=${ORG1} -T ${LDSCRIPT} -o ${.TARGET} gptldr.o CLEANFILES+= gptzfsboot.bin gptzfsboot.out zfsboot.o sio.o cons.o \ drv.o gpt.o ${OPENCRYPTO_XTS} @@ -67,7 +67,7 @@ gptzfsboot.bin: gptzfsboot.out gptzfsboot.out: ${BTXCRT} zfsboot.o sio.o gpt.o drv.o cons.o \ ${OPENCRYPTO_XTS} - ${LD} ${LD_FLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} + ${LD} ${LD_FLAGS} --defsym ORG=${ORG2} -T ${LDSCRIPT} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} zfsboot.o: ${ZFSSRC}/zfsimpl.c diff --git a/stand/i386/isoboot/Makefile b/stand/i386/isoboot/Makefile index 591dcf7df4c6..9fcd1f357231 100644 --- a/stand/i386/isoboot/Makefile +++ b/stand/i386/isoboot/Makefile @@ -53,7 +53,7 @@ gptldr.bin: gptldr.out ${OBJCOPY} -S -O binary gptldr.out ${.TARGET} gptldr.out: gptldr.o - ${LD} ${LD_FLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} gptldr.o + ${LD} ${LD_FLAGS} -e start --defsym ORG=${ORG1} -T ${LDSCRIPT} -o ${.TARGET} gptldr.o CLEANFILES+= isoboot.bin isoboot.out isoboot.o sio.o drv.o \ cons.o ${OPENCRYPTO_XTS} @@ -62,6 +62,6 @@ isoboot.bin: isoboot.out ${OBJCOPY} -S -O binary isoboot.out ${.TARGET} isoboot.out: ${BTXCRT} isoboot.o sio.o drv.o cons.o ${OPENCRYPTO_XTS} - ${LD} ${LD_FLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} + ${LD} ${LD_FLAGS} --defsym ORG=${ORG2} -T ${LDSCRIPT} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} .include diff --git a/stand/i386/loader/Makefile b/stand/i386/loader/Makefile index d0611ef6a4d9..b74ef9007d97 100644 --- a/stand/i386/loader/Makefile +++ b/stand/i386/loader/Makefile @@ -46,8 +46,10 @@ HELP_FILES= ${.CURDIR}/help.i386 CLEANFILES+= ${LOADER} ${LOADER}.bin +ORG= 0x0 + CFLAGS+= -Wall -LDFLAGS+= -static -Ttext 0x0 -Wl,--gc-sections +LDFLAGS+= -static ${LDFLAGS_ORG} -Wl,--gc-sections # i386 standalone support library LIBI386= ${BOOTOBJ}/i386/libi386/libi386.a diff --git a/stand/i386/zfsboot/Makefile b/stand/i386/zfsboot/Makefile index 6bffd4591f3d..422bce0e5b88 100644 --- a/stand/i386/zfsboot/Makefile +++ b/stand/i386/zfsboot/Makefile @@ -49,7 +49,7 @@ zfsboot1: zfsldr.out ${OBJCOPY} -S -O binary zfsldr.out ${.TARGET} zfsldr.out: zfsldr.o - ${LD} ${LD_FLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} zfsldr.o + ${LD} ${LD_FLAGS} -e start --defsym ORG=${ORG1} -T ${LDSCRIPT} -o ${.TARGET} zfsldr.o CLEANFILES+= zfsboot2 zfsboot.ld zfsboot.ldr zfsboot.bin zfsboot.out \ zfsboot.o zfsboot.s zfsboot.s.tmp sio.o cons.o drv.o @@ -75,7 +75,7 @@ zfsboot.bin: zfsboot.out ${OBJCOPY} -S -O binary zfsboot.out ${.TARGET} zfsboot.out: ${BTXCRT} zfsboot.o sio.o drv.o cons.o - ${LD} ${LD_FLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} + ${LD} ${LD_FLAGS} --defsym ORG=${ORG2} -T ${LDSCRIPT} -o ${.TARGET} ${.ALLSRC} ${LIBSA32} SRCS= zfsboot.c