linux/scripts/link-vmlinux.sh
<<
>>
Prefs
   1#!/bin/sh
   2#
   3# link vmlinux
   4#
   5# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_INIT) and
   6# $(KBUILD_VMLINUX_MAIN). Most are built-in.o files from top-level directories
   7# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
   8# Ordering when linking is important, and $(KBUILD_VMLINUX_INIT) must be first.
   9#
  10# vmlinux
  11#   ^
  12#   |
  13#   +-< $(KBUILD_VMLINUX_INIT)
  14#   |   +--< init/version.o + more
  15#   |
  16#   +--< $(KBUILD_VMLINUX_MAIN)
  17#   |    +--< drivers/built-in.o mm/built-in.o + more
  18#   |
  19#   +-< ${kallsymso} (see description in KALLSYMS section)
  20#
  21# vmlinux version (uname -v) cannot be updated during normal
  22# descending-into-subdirs phase since we do not yet know if we need to
  23# update vmlinux.
  24# Therefore this step is delayed until just before final link of vmlinux.
  25#
  26# System.map is generated to document addresses of all kernel symbols
  27
  28# Error out on error
  29set -e
  30
  31# Nice output in kbuild format
  32# Will be supressed by "make -s"
  33info()
  34{
  35        if [ "${quiet}" != "silent_" ]; then
  36                printf "  %-7s %s\n" ${1} ${2}
  37        fi
  38}
  39
  40# Link of vmlinux.o used for section mismatch analysis
  41# ${1} output file
  42modpost_link()
  43{
  44        ${LD} ${LDFLAGS} -r -o ${1} ${KBUILD_VMLINUX_INIT}                   \
  45                --start-group ${KBUILD_VMLINUX_MAIN} --end-group
  46}
  47
  48# Link of vmlinux
  49# ${1} - optional extra .o files
  50# ${2} - output file
  51vmlinux_link()
  52{
  53        local lds="${objtree}/${KBUILD_LDS}"
  54
  55        if [ "${SRCARCH}" != "um" ]; then
  56                ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2}                  \
  57                        -T ${lds} ${KBUILD_VMLINUX_INIT}                     \
  58                        --start-group ${KBUILD_VMLINUX_MAIN} --end-group ${1}
  59        else
  60                ${CC} ${CFLAGS_vmlinux} -o ${2}                              \
  61                        -Wl,-T,${lds} ${KBUILD_VMLINUX_INIT}                 \
  62                        -Wl,--start-group                                    \
  63                                 ${KBUILD_VMLINUX_MAIN}                      \
  64                        -Wl,--end-group                                      \
  65                        -lutil ${1}
  66                rm -f linux
  67        fi
  68}
  69
  70
  71# Create ${2} .o file with all symbols from the ${1} object file
  72kallsyms()
  73{
  74        info KSYM ${2}
  75        local kallsymopt;
  76
  77        if [ -n "${CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX}" ]; then
  78                kallsymopt="${kallsymopt} --symbol-prefix=_"
  79        fi
  80
  81        if [ -n "${CONFIG_KALLSYMS_ALL}" ]; then
  82                kallsymopt="${kallsymopt} --all-symbols"
  83        fi
  84
  85        kallsymopt="${kallsymopt} --page-offset=$CONFIG_PAGE_OFFSET"
  86
  87        local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL}               \
  88                      ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}"
  89
  90        ${NM} -n ${1} | \
  91                scripts/kallsyms ${kallsymopt} | \
  92                ${CC} ${aflags} -c -o ${2} -x assembler-with-cpp -
  93}
  94
  95# Create map file with all symbols from ${1}
  96# See mksymap for additional details
  97mksysmap()
  98{
  99        ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2}
 100}
 101
 102sortextable()
 103{
 104        ${objtree}/scripts/sortextable ${1}
 105}
 106
 107# Delete output files in case of error
 108trap cleanup SIGHUP SIGINT SIGQUIT SIGTERM ERR
 109cleanup()
 110{
 111        rm -f .old_version
 112        rm -f .tmp_System.map
 113        rm -f .tmp_kallsyms*
 114        rm -f .tmp_version
 115        rm -f .tmp_vmlinux*
 116        rm -f System.map
 117        rm -f vmlinux
 118        rm -f vmlinux.o
 119}
 120
 121#
 122#
 123# Use "make V=1" to debug this script
 124case "${KBUILD_VERBOSE}" in
 125*1*)
 126        set -x
 127        ;;
 128esac
 129
 130if [ "$1" = "clean" ]; then
 131        cleanup
 132        exit 0
 133fi
 134
 135# We need access to CONFIG_ symbols
 136case "${KCONFIG_CONFIG}" in
 137*/*)
 138        . "${KCONFIG_CONFIG}"
 139        ;;
 140*)
 141        # Force using a file from the current directory
 142        . "./${KCONFIG_CONFIG}"
 143esac
 144
 145#link vmlinux.o
 146info LD vmlinux.o
 147modpost_link vmlinux.o
 148
 149# modpost vmlinux.o to check for section mismatches
 150${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o
 151
 152# Update version
 153info GEN .version
 154if [ ! -r .version ]; then
 155        rm -f .version;
 156        echo 1 >.version;
 157else
 158        mv .version .old_version;
 159        expr 0$(cat .old_version) + 1 >.version;
 160fi;
 161
 162# final build of init/
 163${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init
 164
 165kallsymso=""
 166kallsyms_vmlinux=""
 167if [ -n "${CONFIG_KALLSYMS}" ]; then
 168
 169        # kallsyms support
 170        # Generate section listing all symbols and add it into vmlinux
 171        # It's a three step process:
 172        # 1)  Link .tmp_vmlinux1 so it has all symbols and sections,
 173        #     but __kallsyms is empty.
 174        #     Running kallsyms on that gives us .tmp_kallsyms1.o with
 175        #     the right size
 176        # 2)  Link .tmp_vmlinux2 so it now has a __kallsyms section of
 177        #     the right size, but due to the added section, some
 178        #     addresses have shifted.
 179        #     From here, we generate a correct .tmp_kallsyms2.o
 180        # 2a) We may use an extra pass as this has been necessary to
 181        #     woraround some alignment related bugs.
 182        #     KALLSYMS_EXTRA_PASS=1 is used to trigger this.
 183        # 3)  The correct ${kallsymso} is linked into the final vmlinux.
 184        #
 185        # a)  Verify that the System.map from vmlinux matches the map from
 186        #     ${kallsymso}.
 187
 188        kallsymso=.tmp_kallsyms2.o
 189        kallsyms_vmlinux=.tmp_vmlinux2
 190
 191        # step 1
 192        vmlinux_link "" .tmp_vmlinux1
 193        kallsyms .tmp_vmlinux1 .tmp_kallsyms1.o
 194
 195        # step 2
 196        vmlinux_link .tmp_kallsyms1.o .tmp_vmlinux2
 197        kallsyms .tmp_vmlinux2 .tmp_kallsyms2.o
 198
 199        # step 2a
 200        if [ -n "${KALLSYMS_EXTRA_PASS}" ]; then
 201                kallsymso=.tmp_kallsyms3.o
 202                kallsyms_vmlinux=.tmp_vmlinux3
 203
 204                vmlinux_link .tmp_kallsyms2.o .tmp_vmlinux3
 205
 206                kallsyms .tmp_vmlinux3 .tmp_kallsyms3.o
 207        fi
 208fi
 209
 210info LD vmlinux
 211vmlinux_link "${kallsymso}" vmlinux
 212
 213if [ -n "${CONFIG_BUILDTIME_EXTABLE_SORT}" ]; then
 214        info SORTEX vmlinux
 215        sortextable vmlinux
 216fi
 217
 218info SYSMAP System.map
 219mksysmap vmlinux System.map
 220
 221# step a (see comment above)
 222if [ -n "${CONFIG_KALLSYMS}" ]; then
 223        mksysmap ${kallsyms_vmlinux} .tmp_System.map
 224
 225        if ! cmp -s System.map .tmp_System.map; then
 226                echo >&2 Inconsistent kallsyms data
 227                echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
 228                cleanup
 229                exit 1
 230        fi
 231fi
 232
 233# We made a new kernel - delete old version file
 234rm -f .old_version
 235
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.