diff options
Diffstat (limited to 'scripts/link-vmlinux.sh')
-rwxr-xr-x | scripts/link-vmlinux.sh | 105 |
1 files changed, 58 insertions, 47 deletions
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 518c70b8db50..f7b2503cdba9 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -45,7 +45,6 @@ info() # Link of vmlinux # ${1} - output file -# ${2}, ${3}, ... - optional extra .o files vmlinux_link() { local output=${1} @@ -90,7 +89,7 @@ vmlinux_link() ldflags="${ldflags} ${wl}--script=${objtree}/${KBUILD_LDS}" # The kallsyms linking does not need debug symbols included. - if [ "$output" != "${output#.tmp_vmlinux.kallsyms}" ] ; then + if [ -n "${strip_debug}" ] ; then ldflags="${ldflags} ${wl}--strip-debug" fi @@ -101,15 +100,15 @@ vmlinux_link() ${ld} ${ldflags} -o ${output} \ ${wl}--whole-archive ${objs} ${wl}--no-whole-archive \ ${wl}--start-group ${libs} ${wl}--end-group \ - $@ ${ldlibs} + ${kallsymso} ${btf_vmlinux_bin_o} ${ldlibs} } # generate .BTF typeinfo from DWARF debuginfo # ${1} - vmlinux image -# ${2} - file to dump raw BTF data into gen_btf() { local pahole_ver + local btf_data=${1}.btf.o if ! [ -x "$(command -v ${PAHOLE})" ]; then echo >&2 "BTF: ${1}: pahole (${PAHOLE}) is not available" @@ -122,18 +121,16 @@ gen_btf() return 1 fi - vmlinux_link ${1} - - info "BTF" ${2} + info BTF "${btf_data}" LLVM_OBJCOPY="${OBJCOPY}" ${PAHOLE} -J ${PAHOLE_FLAGS} ${1} - # Create ${2} which contains just .BTF section but no symbols. Add + # Create ${btf_data} 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 + --strip-all ${1} "${btf_data}" 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 @@ -141,10 +138,12 @@ gen_btf() else et_rel='\1\0' fi - printf "${et_rel}" | dd of=${2} conv=notrunc bs=1 seek=16 status=none + printf "${et_rel}" | dd of="${btf_data}" conv=notrunc bs=1 seek=16 status=none + + btf_vmlinux_bin_o=${btf_data} } -# Create ${2} .S file with all symbols from the ${1} object file +# Create ${2}.o file with all symbols from the ${1} object file kallsyms() { local kallsymopt; @@ -157,35 +156,27 @@ kallsyms() kallsymopt="${kallsymopt} --absolute-percpu" fi - if is_enabled CONFIG_KALLSYMS_BASE_RELATIVE; then - kallsymopt="${kallsymopt} --base-relative" - fi - if is_enabled CONFIG_LTO_CLANG; then kallsymopt="${kallsymopt} --lto-clang" fi - info KSYMS ${2} - scripts/kallsyms ${kallsymopt} ${1} > ${2} + info KSYMS "${2}.S" + scripts/kallsyms ${kallsymopt} "${1}" > "${2}.S" + + info AS "${2}.o" + ${CC} ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS} \ + ${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} -c -o "${2}.o" "${2}.S" + + kallsymso=${2}.o } -# Perform one step in kallsyms generation, including temporary linking of -# vmlinux. -kallsyms_step() +# Perform kallsyms for the given temporary vmlinux. +sysmap_and_kallsyms() { - 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 - kallsyms ${kallsyms_vmlinux}.syms ${kallsyms_S} + mksysmap "${1}" "${1}.syms" + kallsyms "${1}.syms" "${1}.kallsyms" - info AS ${kallsymso} - ${CC} ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS} \ - ${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \ - -c -o ${kallsymso} ${kallsyms_S} + kallsyms_sysmap=${1}.syms } # Create map file with all symbols from ${1} @@ -223,26 +214,40 @@ fi ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o -btf_vmlinux_bin_o="" +btf_vmlinux_bin_o= +kallsymso= +strip_debug= + +if is_enabled CONFIG_KALLSYMS; then + kallsyms /dev/null .tmp_vmlinux0.kallsyms +fi + +if is_enabled CONFIG_KALLSYMS || is_enabled CONFIG_DEBUG_INFO_BTF; then + + # The kallsyms linking does not need debug symbols, but the BTF does. + if ! is_enabled CONFIG_DEBUG_INFO_BTF; then + strip_debug=1 + fi + + vmlinux_link .tmp_vmlinux1 +fi + 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 + if ! gen_btf .tmp_vmlinux1; 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 is_enabled CONFIG_KALLSYMS; then # kallsyms support # Generate section listing all symbols and add it into vmlinux - # It's a three step process: + # It's a four step process: + # 0) Generate a dummy __kallsyms with empty symbol list. # 1) Link .tmp_vmlinux.kallsyms1 so it has all symbols and sections, - # but __kallsyms is empty. + # with a dummy __kallsyms. # Running kallsyms on that gives us .tmp_kallsyms1.o with # the right size # 2) Link .tmp_vmlinux.kallsyms2 so it now has a __kallsyms section of @@ -261,19 +266,25 @@ if is_enabled CONFIG_KALLSYMS; then # a) Verify that the System.map from vmlinux matches the map from # ${kallsymso}. - kallsyms_step 1 - kallsyms_step 2 + # The kallsyms linking does not need debug symbols included. + strip_debug=1 - # step 3 - size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso_prev}) + sysmap_and_kallsyms .tmp_vmlinux1 + size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso}) + + vmlinux_link .tmp_vmlinux2 + sysmap_and_kallsyms .tmp_vmlinux2 size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso}) if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then - kallsyms_step 3 + vmlinux_link .tmp_vmlinux3 + sysmap_and_kallsyms .tmp_vmlinux3 fi fi -vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o} +strip_debug= + +vmlinux_link vmlinux # fill in BTF IDs if is_enabled CONFIG_DEBUG_INFO_BTF && is_enabled CONFIG_BPF; then @@ -293,7 +304,7 @@ fi # step a (see comment above) if is_enabled CONFIG_KALLSYMS; then - if ! cmp -s System.map ${kallsyms_vmlinux}.syms; then + if ! cmp -s System.map "${kallsyms_sysmap}"; then echo >&2 Inconsistent kallsyms data echo >&2 'Try "make KALLSYMS_EXTRA_PASS=1" as a workaround' exit 1 |