kbuild: deb-pkg: use build ID instead of debug link for dbg package

There are two ways of managing separate debug info files:

 [1] The executable contains the .gnu_debuglink section, which specifies
     the name and the CRC of the separate debug info file.

 [2] The executable contains a build ID, and the corresponding debug info
     file is placed in the .build-id directory.

We could do both, but the former, which 'make deb-pkg' currently does,
results in complicated installation steps because we need to manually
strip the debug sections, create debug links, and re-sign the modules.
Besides, it is not working with module compression.

This commit abandons the approach [1], and instead opts for [2].

Debian kernel commit de26137e2a9f ("Drop not needed extra step to add
debug links") also stopped adding debug links.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Masahiro Yamada 2023-12-26 23:33:59 +09:00
parent 5e73758b43
commit 16c36f8864
1 changed files with 13 additions and 19 deletions

View File

@ -49,7 +49,7 @@ install_linux_image () {
${MAKE} -f ${srctree}/Makefile INSTALL_DTBS_PATH="${pdir}/usr/lib/linux-image-${KERNELRELEASE}" dtbs_install
fi
${MAKE} -f ${srctree}/Makefile INSTALL_MOD_PATH="${pdir}" modules_install
${MAKE} -f ${srctree}/Makefile INSTALL_MOD_PATH="${pdir}" INSTALL_MOD_STRIP=1 modules_install
rm -f "${pdir}/lib/modules/${KERNELRELEASE}/build"
# Install the kernel
@ -110,25 +110,21 @@ install_linux_image () {
install_linux_image_dbg () {
pdir=$1
image_pdir=$2
rm -rf ${pdir}
for module in $(find ${image_pdir}/lib/modules/ -name *.ko -printf '%P\n'); do
module=lib/modules/${module}
mkdir -p $(dirname ${pdir}/usr/lib/debug/${module})
# only keep debug symbols in the debug file
${OBJCOPY} --only-keep-debug ${image_pdir}/${module} ${pdir}/usr/lib/debug/${module}
# strip original module from debug symbols
${OBJCOPY} --strip-debug ${image_pdir}/${module}
# then add a link to those
${OBJCOPY} --add-gnu-debuglink=${pdir}/usr/lib/debug/${module} ${image_pdir}/${module}
done
# Parse modules.order directly because 'make modules_install' may sign,
# compress modules, and then run unneeded depmod.
while read -r mod; do
mod="${mod%.o}.ko"
dbg="${pdir}/usr/lib/debug/lib/modules/${KERNELRELEASE}/kernel/${mod}"
buildid=$("${READELF}" -n "${mod}" | sed -n 's@^.*Build ID: \(..\)\(.*\)@\1/\2@p')
link="${pdir}/usr/lib/debug/.build-id/${buildid}.debug"
# re-sign stripped modules
if is_enabled CONFIG_MODULE_SIG_ALL; then
${MAKE} -f ${srctree}/Makefile INSTALL_MOD_PATH="${image_pdir}" modules_sign
fi
mkdir -p "${dbg%/*}" "${link%/*}"
"${OBJCOPY}" --only-keep-debug "${mod}" "${dbg}"
ln -sf --relative "${dbg}" "${link}"
done < modules.order
# Build debug package
# Different tools want the image in different locations
@ -176,9 +172,7 @@ for package in ${packages_enabled}
do
case ${package} in
*-dbg)
# This must be done after linux-image, that is, we expect the
# debug package appears after linux-image in debian/control.
install_linux_image_dbg debian/linux-image-dbg debian/linux-image;;
install_linux_image_dbg debian/linux-image-dbg;;
linux-image-*|user-mode-linux-*)
install_linux_image debian/linux-image ${package};;
linux-libc-dev)