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-rwxr-xr-xscripts/link-vmlinux.sh319
1 files changed, 165 insertions, 154 deletions
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index a7124f895b24..7862a8101747 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -3,17 +3,15 @@
#
# link vmlinux
#
-# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_OBJS) and
-# $(KBUILD_VMLINUX_LIBS). Most are built-in.a files from top-level directories
-# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
+# vmlinux is linked from the objects in vmlinux.a and $(KBUILD_VMLINUX_LIBS).
+# vmlinux.a contains objects that are linked unconditionally.
# $(KBUILD_VMLINUX_LIBS) are archives which are linked conditionally
# (not within --whole-archive), and do not require symbol indexes added.
#
# vmlinux
# ^
# |
-# +--< $(KBUILD_VMLINUX_OBJS)
-# | +--< init/built-in.a drivers/built-in.a mm/built-in.a + more
+# +--< vmlinux.a
# |
# +--< $(KBUILD_VMLINUX_LIBS)
# | +--< lib/lib.a + more
@@ -30,153 +28,188 @@
# Error out on error
set -e
+LD="$1"
+KBUILD_LDFLAGS="$2"
+LDFLAGS_vmlinux="$3"
+
+is_enabled() {
+ grep -q "^$1=y" include/config/auto.conf
+}
+
# Nice output in kbuild format
# Will be supressed by "make -s"
info()
{
- if [ "${quiet}" != "silent_" ]; then
- printf " %-7s %s\n" "${1}" "${2}"
- fi
+ printf " %-7s %s\n" "${1}" "${2}"
}
-# Link of vmlinux.o used for section mismatch analysis
-# ${1} output file
-modpost_link()
+# Link of vmlinux
+# ${1} - output file
+# ${2}, ${3}, ... - optional extra .o files
+vmlinux_link()
{
- local objects
+ local output=${1}
+ local objs
+ local libs
+ local ld
+ local ldflags
+ local ldlibs
+
+ info LD ${output}
+
+ # skip output file argument
+ shift
+
+ if is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT; then
+ # Use vmlinux.o instead of performing the slow LTO link again.
+ objs=vmlinux.o
+ libs=
+ else
+ objs=vmlinux.a
+ libs="${KBUILD_VMLINUX_LIBS}"
+ fi
- objects="--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
- --no-whole-archive \
- --start-group \
- ${KBUILD_VMLINUX_LIBS} \
- --end-group"
+ if is_enabled CONFIG_MODULES; then
+ objs="${objs} .vmlinux.export.o"
+ fi
- ${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${objects}
-}
+ objs="${objs} init/version-timestamp.o"
-# Link of vmlinux
-# ${1} - optional extra .o files
-# ${2} - output file
-vmlinux_link()
-{
- local lds="${objtree}/${KBUILD_LDS}"
- local objects
-
- if [ "${SRCARCH}" != "um" ]; then
- objects="--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
- --no-whole-archive \
- --start-group \
- ${KBUILD_VMLINUX_LIBS} \
- --end-group \
- ${1}"
-
- ${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} -o ${2} \
- -T ${lds} ${objects}
+ if [ "${SRCARCH}" = "um" ]; then
+ wl=-Wl,
+ ld="${CC}"
+ ldflags="${CFLAGS_vmlinux}"
+ ldlibs="-lutil -lrt -lpthread"
else
- objects="-Wl,--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
- -Wl,--no-whole-archive \
- -Wl,--start-group \
- ${KBUILD_VMLINUX_LIBS} \
- -Wl,--end-group \
- ${1}"
-
- ${CC} ${CFLAGS_vmlinux} -o ${2} \
- -Wl,-T,${lds} \
- ${objects} \
- -lutil -lrt -lpthread
- rm -f linux
+ wl=
+ ld="${LD}"
+ ldflags="${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux}"
+ ldlibs=
fi
+
+ ldflags="${ldflags} ${wl}--script=${objtree}/${KBUILD_LDS}"
+
+ # The kallsyms linking does not need debug symbols included.
+ if [ "$output" != "${output#.tmp_vmlinux.kallsyms}" ] ; then
+ ldflags="${ldflags} ${wl}--strip-debug"
+ fi
+
+ if is_enabled CONFIG_VMLINUX_MAP; then
+ ldflags="${ldflags} ${wl}-Map=${output}.map"
+ fi
+
+ ${ld} ${ldflags} -o ${output} \
+ ${wl}--whole-archive ${objs} ${wl}--no-whole-archive \
+ ${wl}--start-group ${libs} ${wl}--end-group \
+ $@ ${ldlibs}
}
# generate .BTF typeinfo from DWARF debuginfo
+# ${1} - vmlinux image
+# ${2} - file to dump raw BTF data into
gen_btf()
{
- local pahole_ver;
+ local pahole_ver
if ! [ -x "$(command -v ${PAHOLE})" ]; then
- info "BTF" "${1}: pahole (${PAHOLE}) is not available"
- return 0
+ echo >&2 "BTF: ${1}: pahole (${PAHOLE}) is not available"
+ return 1
fi
pahole_ver=$(${PAHOLE} --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/')
- if [ "${pahole_ver}" -lt "113" ]; then
- info "BTF" "${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.13"
- return 0
+ if [ "${pahole_ver}" -lt "116" ]; then
+ echo >&2 "BTF: ${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.16"
+ return 1
fi
- info "BTF" ${1}
- LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J ${1}
+ vmlinux_link ${1}
+
+ info "BTF" ${2}
+ LLVM_OBJCOPY="${OBJCOPY}" ${PAHOLE} -J ${PAHOLE_FLAGS} ${1}
+
+ # Create ${2} which contains just .BTF section but no symbols. Add
+ # SHF_ALLOC because .BTF will be part of the vmlinux image. --strip-all
+ # deletes all symbols including __start_BTF and __stop_BTF, which will
+ # be redefined in the linker script. Add 2>/dev/null to suppress GNU
+ # objcopy warnings: "empty loadable segment detected at ..."
+ ${OBJCOPY} --only-section=.BTF --set-section-flags .BTF=alloc,readonly \
+ --strip-all ${1} ${2} 2>/dev/null
+ # Change e_type to ET_REL so that it can be used to link final vmlinux.
+ # GNU ld 2.35+ and lld do not allow an ET_EXEC input.
+ if is_enabled CONFIG_CPU_BIG_ENDIAN; then
+ et_rel='\0\1'
+ else
+ et_rel='\1\0'
+ fi
+ printf "${et_rel}" | dd of=${2} conv=notrunc bs=1 seek=16 status=none
}
-# Create ${2} .o file with all symbols from the ${1} object file
+# Create ${2} .S file with all symbols from the ${1} object file
kallsyms()
{
- info KSYM ${2}
local kallsymopt;
- if [ -n "${CONFIG_KALLSYMS_ALL}" ]; then
+ if is_enabled CONFIG_KALLSYMS_ALL; then
kallsymopt="${kallsymopt} --all-symbols"
fi
- if [ -n "${CONFIG_KALLSYMS_ABSOLUTE_PERCPU}" ]; then
+ if is_enabled CONFIG_KALLSYMS_ABSOLUTE_PERCPU; then
kallsymopt="${kallsymopt} --absolute-percpu"
fi
- if [ -n "${CONFIG_KALLSYMS_BASE_RELATIVE}" ]; then
+ if is_enabled CONFIG_KALLSYMS_BASE_RELATIVE; then
kallsymopt="${kallsymopt} --base-relative"
fi
- local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \
- ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}"
+ if is_enabled CONFIG_LTO_CLANG; then
+ kallsymopt="${kallsymopt} --lto-clang"
+ fi
- local afile="`basename ${2} .o`.S"
+ info KSYMS ${2}
+ scripts/kallsyms ${kallsymopt} ${1} > ${2}
+}
- ${NM} -n ${1} | scripts/kallsyms ${kallsymopt} > ${afile}
- ${CC} ${aflags} -c -o ${2} ${afile}
+# Perform one step in kallsyms generation, including temporary linking of
+# vmlinux.
+kallsyms_step()
+{
+ kallsymso_prev=${kallsymso}
+ kallsyms_vmlinux=.tmp_vmlinux.kallsyms${1}
+ kallsymso=${kallsyms_vmlinux}.o
+ kallsyms_S=${kallsyms_vmlinux}.S
+
+ vmlinux_link ${kallsyms_vmlinux} "${kallsymso_prev}" ${btf_vmlinux_bin_o}
+ mksysmap ${kallsyms_vmlinux} ${kallsyms_vmlinux}.syms ${kallsymso_prev}
+ kallsyms ${kallsyms_vmlinux}.syms ${kallsyms_S}
+
+ info AS ${kallsyms_S}
+ ${CC} ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS} \
+ ${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \
+ -c -o ${kallsymso} ${kallsyms_S}
}
# Create map file with all symbols from ${1}
# See mksymap for additional details
mksysmap()
{
- ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2}
+ info NM ${2}
+ ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2} ${3}
}
-sortextable()
+sorttable()
{
- ${objtree}/scripts/sortextable ${1}
+ ${objtree}/scripts/sorttable ${1}
}
# Delete output files in case of error
cleanup()
{
- rm -f .tmp_System.map
- rm -f .tmp_kallsyms*
- rm -f .tmp_vmlinux*
+ rm -f .btf.*
rm -f System.map
rm -f vmlinux
- rm -f vmlinux.o
-}
-
-on_exit()
-{
- if [ $? -ne 0 ]; then
- cleanup
- fi
+ rm -f vmlinux.map
}
-trap on_exit EXIT
-on_signals()
-{
- exit 1
-}
-trap on_signals HUP INT QUIT TERM
-
-#
-#
# Use "make V=1" to debug this script
case "${KBUILD_VERBOSE}" in
*1*)
@@ -189,47 +222,34 @@ if [ "$1" = "clean" ]; then
exit 0
fi
-# We need access to CONFIG_ symbols
-. include/config/auto.conf
-
-# Update version
-info GEN .version
-if [ -r .version ]; then
- VERSION=$(expr 0$(cat .version) + 1)
- echo $VERSION > .version
-else
- rm -f .version
- echo 1 > .version
-fi;
-
-# final build of init/
-${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init
+${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o
-#link vmlinux.o
-info LD vmlinux.o
-modpost_link vmlinux.o
-
-# modpost vmlinux.o to check for section mismatches
-${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o
-
-info MODINFO modules.builtin.modinfo
-${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo
+btf_vmlinux_bin_o=""
+if is_enabled CONFIG_DEBUG_INFO_BTF; then
+ btf_vmlinux_bin_o=.btf.vmlinux.bin.o
+ if ! gen_btf .tmp_vmlinux.btf $btf_vmlinux_bin_o ; then
+ echo >&2 "Failed to generate BTF for vmlinux"
+ echo >&2 "Try to disable CONFIG_DEBUG_INFO_BTF"
+ exit 1
+ fi
+fi
kallsymso=""
+kallsymso_prev=""
kallsyms_vmlinux=""
-if [ -n "${CONFIG_KALLSYMS}" ]; then
+if is_enabled CONFIG_KALLSYMS; then
# kallsyms support
# Generate section listing all symbols and add it into vmlinux
# It's a three step process:
- # 1) Link .tmp_vmlinux1 so it has all symbols and sections,
+ # 1) Link .tmp_vmlinux.kallsyms1 so it has all symbols and sections,
# but __kallsyms is empty.
# Running kallsyms on that gives us .tmp_kallsyms1.o with
# the right size
- # 2) Link .tmp_vmlinux2 so it now has a __kallsyms section of
+ # 2) Link .tmp_vmlinux.kallsyms2 so it now has a __kallsyms section of
# the right size, but due to the added section, some
# addresses have shifted.
- # From here, we generate a correct .tmp_kallsyms2.o
+ # From here, we generate a correct .tmp_vmlinux.kallsyms2.o
# 3) That link may have expanded the kernel image enough that
# more linker branch stubs / trampolines had to be added, which
# introduces new names, which further expands kallsyms. Do another
@@ -242,53 +262,44 @@ if [ -n "${CONFIG_KALLSYMS}" ]; then
# a) Verify that the System.map from vmlinux matches the map from
# ${kallsymso}.
- kallsymso=.tmp_kallsyms2.o
- kallsyms_vmlinux=.tmp_vmlinux2
-
- # step 1
- vmlinux_link "" .tmp_vmlinux1
- kallsyms .tmp_vmlinux1 .tmp_kallsyms1.o
-
- # step 2
- vmlinux_link .tmp_kallsyms1.o .tmp_vmlinux2
- kallsyms .tmp_vmlinux2 .tmp_kallsyms2.o
+ kallsyms_step 1
+ kallsyms_step 2
# step 3
- size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms1.o)
- size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms2.o)
+ size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso_prev})
+ size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso})
if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then
- kallsymso=.tmp_kallsyms3.o
- kallsyms_vmlinux=.tmp_vmlinux3
-
- vmlinux_link .tmp_kallsyms2.o .tmp_vmlinux3
-
- kallsyms .tmp_vmlinux3 .tmp_kallsyms3.o
+ kallsyms_step 3
fi
fi
-info LD vmlinux
-vmlinux_link "${kallsymso}" vmlinux
+vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o}
-if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then
- gen_btf vmlinux
+# fill in BTF IDs
+if is_enabled CONFIG_DEBUG_INFO_BTF && is_enabled CONFIG_BPF; then
+ info BTFIDS vmlinux
+ ${RESOLVE_BTFIDS} vmlinux
fi
-if [ -n "${CONFIG_BUILDTIME_EXTABLE_SORT}" ]; then
- info SORTEX vmlinux
- sortextable vmlinux
-fi
+mksysmap vmlinux System.map ${kallsymso}
-info SYSMAP System.map
-mksysmap vmlinux System.map
+if is_enabled CONFIG_BUILDTIME_TABLE_SORT; then
+ info SORTTAB vmlinux
+ if ! sorttable vmlinux; then
+ echo >&2 Failed to sort kernel tables
+ exit 1
+ fi
+fi
# step a (see comment above)
-if [ -n "${CONFIG_KALLSYMS}" ]; then
- mksysmap ${kallsyms_vmlinux} .tmp_System.map
-
- if ! cmp -s System.map .tmp_System.map; then
+if is_enabled CONFIG_KALLSYMS; then
+ if ! cmp -s System.map ${kallsyms_vmlinux}.syms; then
echo >&2 Inconsistent kallsyms data
- echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
+ echo >&2 'Try "make KALLSYMS_EXTRA_PASS=1" as a workaround'
exit 1
fi
fi
+
+# For fixdep
+echo "vmlinux: $0" > .vmlinux.d
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-14 21:38:53 +0000