1#!/bin/sh 2# 3# link vmlinux 4# 5# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_INIT) and 6# $(KBUILD_VMLINUX_MAIN) and $(KBUILD_VMLINUX_LIBS). Most are built-in.o files 7# from top-level directories in the kernel tree, others are specified in 8# arch/$(ARCH)/Makefile. Ordering when linking is important, and 9# $(KBUILD_VMLINUX_INIT) must be first. $(KBUILD_VMLINUX_LIBS) are archives 10# which are linked conditionally (not within --whole-archive), and do not 11# require symbol indexes added. 12# 13# vmlinux 14# ^ 15# | 16# +-< $(KBUILD_VMLINUX_INIT) 17# | +--< init/version.o + more 18# | 19# +--< $(KBUILD_VMLINUX_MAIN) 20# | +--< drivers/built-in.o mm/built-in.o + more 21# | 22# +--< $(KBUILD_VMLINUX_LIBS) 23# | +--< lib/lib.a + more 24# | 25# +-< ${kallsymso} (see description in KALLSYMS section) 26# 27# vmlinux version (uname -v) cannot be updated during normal 28# descending-into-subdirs phase since we do not yet know if we need to 29# update vmlinux. 30# Therefore this step is delayed until just before final link of vmlinux. 31# 32# System.map is generated to document addresses of all kernel symbols 33 34# Error out on error 35set -e 36 37# Nice output in kbuild format 38# Will be supressed by "make -s" 39info() 40{ 41 if [ "${quiet}" != "silent_" ]; then 42 printf " %-7s %s\n" ${1} ${2} 43 fi 44} 45 46# Thin archive build here makes a final archive with symbol table and indexes 47# from vmlinux objects INIT and MAIN, which can be used as input to linker. 48# KBUILD_VMLINUX_LIBS archives should already have symbol table and indexes 49# added. 50# 51# Traditional incremental style of link does not require this step 52# 53# built-in.o output file 54# 55archive_builtin() 56{ 57 if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then 58 info AR built-in.o 59 rm -f built-in.o; 60 ${AR} rcsTP${KBUILD_ARFLAGS} built-in.o \ 61 ${KBUILD_VMLINUX_INIT} \ 62 ${KBUILD_VMLINUX_MAIN} 63 fi 64} 65 66# Link of vmlinux.o used for section mismatch analysis 67# ${1} output file 68modpost_link() 69{ 70 local objects 71 72 if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then 73 objects="--whole-archive \ 74 built-in.o \ 75 --no-whole-archive \ 76 --start-group \ 77 ${KBUILD_VMLINUX_LIBS} \ 78 --end-group" 79 else 80 objects="${KBUILD_VMLINUX_INIT} \ 81 --start-group \ 82 ${KBUILD_VMLINUX_MAIN} \ 83 ${KBUILD_VMLINUX_LIBS} \ 84 --end-group" 85 fi 86 ${LD} ${LDFLAGS} -r -o ${1} ${objects} 87} 88 89# Link of vmlinux 90# ${1} - optional extra .o files 91# ${2} - output file 92vmlinux_link() 93{ 94 local lds="${objtree}/${KBUILD_LDS}" 95 local objects 96 97 if [ "${SRCARCH}" != "um" ]; then 98 if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then 99 objects="--whole-archive \ 100 built-in.o \ 101 --no-whole-archive \ 102 --start-group \ 103 ${KBUILD_VMLINUX_LIBS} \ 104 --end-group \ 105 ${1}" 106 else 107 objects="${KBUILD_VMLINUX_INIT} \ 108 --start-group \ 109 ${KBUILD_VMLINUX_MAIN} \ 110 ${KBUILD_VMLINUX_LIBS} \ 111 --end-group \ 112 ${1}" 113 fi 114 115 ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2} \ 116 -T ${lds} ${objects} 117 else 118 if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then 119 objects="-Wl,--whole-archive \ 120 built-in.o \ 121 -Wl,--no-whole-archive \ 122 -Wl,--start-group \ 123 ${KBUILD_VMLINUX_LIBS} \ 124 -Wl,--end-group \ 125 ${1}" 126 else 127 objects="${KBUILD_VMLINUX_INIT} \ 128 -Wl,--start-group \ 129 ${KBUILD_VMLINUX_MAIN} \ 130 ${KBUILD_VMLINUX_LIBS} \ 131 -Wl,--end-group \ 132 ${1}" 133 fi 134 135 ${CC} ${CFLAGS_vmlinux} -o ${2} \ 136 -Wl,-T,${lds} \ 137 ${objects} \ 138 -lutil -lrt -lpthread 139 rm -f linux 140 fi 141} 142 143 144# Create ${2} .o file with all symbols from the ${1} object file 145kallsyms() 146{ 147 info KSYM ${2} 148 local kallsymopt; 149 150 if [ -n "${CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX}" ]; then 151 kallsymopt="${kallsymopt} --symbol-prefix=_" 152 fi 153 154 if [ -n "${CONFIG_KALLSYMS_ALL}" ]; then 155 kallsymopt="${kallsymopt} --all-symbols" 156 fi 157 158 if [ -n "${CONFIG_KALLSYMS_ABSOLUTE_PERCPU}" ]; then 159 kallsymopt="${kallsymopt} --absolute-percpu" 160 fi 161 162 if [ -n "${CONFIG_KALLSYMS_BASE_RELATIVE}" ]; then 163 kallsymopt="${kallsymopt} --base-relative" 164 fi 165 166 local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \ 167 ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}" 168 169 local afile="`basename ${2} .o`.S" 170 171 ${NM} -n ${1} | scripts/kallsyms ${kallsymopt} > ${afile} 172 ${CC} ${aflags} -c -o ${2} ${afile} 173} 174 175# Create map file with all symbols from ${1} 176# See mksymap for additional details 177mksysmap() 178{ 179 ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2} 180} 181 182sortextable() 183{ 184 ${objtree}/scripts/sortextable ${1} 185} 186 187# Delete output files in case of error 188cleanup() 189{ 190 rm -f .old_version 191 rm -f .tmp_System.map 192 rm -f .tmp_kallsyms* 193 rm -f .tmp_version 194 rm -f .tmp_vmlinux* 195 rm -f built-in.o 196 rm -f System.map 197 rm -f vmlinux 198 rm -f vmlinux.o 199} 200 201on_exit() 202{ 203 if [ $? -ne 0 ]; then 204 cleanup 205 fi 206} 207trap on_exit EXIT 208 209on_signals() 210{ 211 exit 1 212} 213trap on_signals HUP INT QUIT TERM 214 215# 216# 217# Use "make V=1" to debug this script 218case "${KBUILD_VERBOSE}" in 219*1*) 220 set -x 221 ;; 222esac 223 224if [ "$1" = "clean" ]; then 225 cleanup 226 exit 0 227fi 228 229# We need access to CONFIG_ symbols 230case "${KCONFIG_CONFIG}" in 231*/*) 232 . "${KCONFIG_CONFIG}" 233 ;; 234*) 235 # Force using a file from the current directory 236 . "./${KCONFIG_CONFIG}" 237esac 238 239# Update version 240info GEN .version 241if [ ! -r .version ]; then 242 rm -f .version; 243 echo 1 >.version; 244else 245 mv .version .old_version; 246 expr 0$(cat .old_version) + 1 >.version; 247fi; 248 249# final build of init/ 250${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init GCC_PLUGINS_CFLAGS="${GCC_PLUGINS_CFLAGS}" 251 252archive_builtin 253 254#link vmlinux.o 255info LD vmlinux.o 256modpost_link vmlinux.o 257 258# modpost vmlinux.o to check for section mismatches 259${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o 260 261kallsymso="" 262kallsyms_vmlinux="" 263if [ -n "${CONFIG_KALLSYMS}" ]; then 264 265 # kallsyms support 266 # Generate section listing all symbols and add it into vmlinux 267 # It's a three step process: 268 # 1) Link .tmp_vmlinux1 so it has all symbols and sections, 269 # but __kallsyms is empty. 270 # Running kallsyms on that gives us .tmp_kallsyms1.o with 271 # the right size 272 # 2) Link .tmp_vmlinux2 so it now has a __kallsyms section of 273 # the right size, but due to the added section, some 274 # addresses have shifted. 275 # From here, we generate a correct .tmp_kallsyms2.o 276 # 3) That link may have expanded the kernel image enough that 277 # more linker branch stubs / trampolines had to be added, which 278 # introduces new names, which further expands kallsyms. Do another 279 # pass if that is the case. In theory it's possible this results 280 # in even more stubs, but unlikely. 281 # KALLSYMS_EXTRA_PASS=1 may also used to debug or work around 282 # other bugs. 283 # 4) The correct ${kallsymso} is linked into the final vmlinux. 284 # 285 # a) Verify that the System.map from vmlinux matches the map from 286 # ${kallsymso}. 287 288 kallsymso=.tmp_kallsyms2.o 289 kallsyms_vmlinux=.tmp_vmlinux2 290 291 # step 1 292 vmlinux_link "" .tmp_vmlinux1 293 kallsyms .tmp_vmlinux1 .tmp_kallsyms1.o 294 295 # step 2 296 vmlinux_link .tmp_kallsyms1.o .tmp_vmlinux2 297 kallsyms .tmp_vmlinux2 .tmp_kallsyms2.o 298 299 # step 3 300 size1=$(stat -c "%s" .tmp_kallsyms1.o) 301 size2=$(stat -c "%s" .tmp_kallsyms2.o) 302 303 if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then 304 kallsymso=.tmp_kallsyms3.o 305 kallsyms_vmlinux=.tmp_vmlinux3 306 307 vmlinux_link .tmp_kallsyms2.o .tmp_vmlinux3 308 309 kallsyms .tmp_vmlinux3 .tmp_kallsyms3.o 310 fi 311fi 312 313info LD vmlinux 314vmlinux_link "${kallsymso}" vmlinux 315 316if [ -n "${CONFIG_BUILDTIME_EXTABLE_SORT}" ]; then 317 info SORTEX vmlinux 318 sortextable vmlinux 319fi 320 321info SYSMAP System.map 322mksysmap vmlinux System.map 323 324# step a (see comment above) 325if [ -n "${CONFIG_KALLSYMS}" ]; then 326 mksysmap ${kallsyms_vmlinux} .tmp_System.map 327 328 if ! cmp -s System.map .tmp_System.map; then 329 echo >&2 Inconsistent kallsyms data 330 echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround 331 exit 1 332 fi 333fi 334 335# We made a new kernel - delete old version file 336rm -f .old_version 337