Successfully build x86 and arm64 kernel headers for new linux versions

Signed-off-by: Dom Del Nano <ddelnano@gmail.com>

Author: ddelnano

tools/docker/Makefile

@@ -74,12 +74,12 @@ LINUX_HEADER_BUILD_DIR := $(BUILD_DIR)/linux_headers
 LINUX_HEADER_ASSETS_BUILD_DIR := $(LINUX_HEADER_BUILD_DIR)/assets
 LINUX_KERNEL_VERSIONS := 4.18.20 \
         5.10.252 \
-	5.14.21 \
-	6.1.167 \
-	6.6.132 \
-	6.12.80 \
-	6.18.21 \
-	6.19.10
+        5.14.21 \
+        6.1.167 \
+        6.6.132 \
+        6.12.80 \
+        6.18.21 \
+        6.19.10
 
 
 LINUX_HEADER_TEMPLATE := linux-headers-%.tar.gz
@@ -114,7 +114,8 @@ elasticsearch_image_tag := "gcr.io/pixie-oss/pixie-dev-public/elasticsearch:$(EL
 
 ## Linux kernel for qemu/BPF tests.
 KERNEL_BUILD_DIR := $(BUILD_DIR)/kernel_build
-KERNEL_BUILD_VERSIONS := 5.10.252 \
+KERNEL_BUILD_VERSIONS := 4.14.309 \
+        5.10.252 \
 	5.14.21 \
 	6.1.167 \
 	6.6.132 \

tools/docker/linux_headers_image/Dockerfile

@@ -27,29 +27,16 @@ RUN apt-get update
 RUN apt-get upgrade -y -q
 RUN apt-get install -y -q build-essential \
   bc \
-  libdw-dev \
   libelf-dev \
   libssl-dev \
   flex \
   bison \
-  kmod \
-  cpio \
   rsync \
   wget \
   binutils-aarch64-linux-gnu \
   gcc-aarch64-linux-gnu \
-  dwarves \
-  debhelper \
   python3
 
-# opensslconf.h lives at the multiarch path (e.g. /usr/include/x86_64-linux-gnu/openssl/).
-# During cross-compilation, dpkg-buildpackage alters include paths so host tools
-# (like scripts/sign-file) can no longer find it. Symlink it to the standard path.
-RUN if [ -f /usr/include/x86_64-linux-gnu/openssl/opensslconf.h ] && \
-       [ ! -f /usr/include/openssl/opensslconf.h ]; then \
-      ln -s /usr/include/x86_64-linux-gnu/openssl/opensslconf.h /usr/include/openssl/opensslconf.h; \
-    fi
-
 WORKDIR /configs
 ADD x86_64_config /configs/x86_64
 ADD arm64_config /configs/arm64

tools/docker/linux_headers_image/build_linux_headers.sh

@@ -49,56 +49,37 @@ mkdir -p "${WORKSPACE}"/src
 pushd "${WORKSPACE}"/src || exit
 
 KERN_MAJ=$(echo "${KERN_VERSION}" | cut -d'.' -f1);
-KERN_MIN=$(echo "${KERN_VERSION}" | cut -d'.' -f2);
 wget -nv http://mirrors.edge.kernel.org/pub/linux/kernel/v"${KERN_MAJ}".x/linux-"${KERN_VERSION}".tar.gz
 
 tar zxf linux-"${KERN_VERSION}".tar.gz
 
 pushd linux-"${KERN_VERSION}" || exit
 
-cp /configs/"${ARCH}" .config
-make ARCH="${ARCH}" olddefconfig
-make ARCH="${ARCH}" clean
-
 LOCALVERSION="-pl"
 
-DEB_ARCH="${ARCH//x86_64/amd64}"
-# binary builds are required for non git trees after linux v6.3 (inclusive).
-# The .deb file suffix is also different.
-TARGET='bindeb-pkg'
-DEB_SUFFIX="-1_${DEB_ARCH}.deb"
-if [ "${KERN_MAJ}" -lt 6 ] || { [ "${KERN_MAJ}" -le 6 ] && [ "${KERN_MIN}" -lt 3 ]; }; then
-    TARGET='deb-pkg'
-    DEB_SUFFIX="${LOCALVERSION}-1_${DEB_ARCH}.deb"
-fi
-echo "Building ${TARGET} for ${KERN_VERSION}${LOCALVERSION} (${ARCH})"
+cp /configs/"${ARCH}" .config
+make ARCH="${ARCH}" olddefconfig
 
-EXTRA_MAKE_ARGS=""
-if [ "${ARCH}" != "$(uname -m)" ]; then
-    # Skip dpkg dependency checks when cross-compiling, since host packages
-    # (e.g. libssl-dev) won't satisfy target arch requirements.
-    EXTRA_MAKE_ARGS="DPKG_FLAGS=-d"
-fi
-make ARCH="${ARCH}" -j "$(nproc)" "${TARGET}" LOCALVERSION="${LOCALVERSION}" ${EXTRA_MAKE_ARGS}
+# Only generate headers — no kernel or module compilation needed.
+# 'make prepare' generates include/generated/ and arch/*/include/generated/
+# which are the only outputs we package.
+echo "Generating headers for ${KERN_VERSION}${LOCALVERSION} (${ARCH})"
+make ARCH="${ARCH}" prepare LOCALVERSION="${LOCALVERSION}"
 
 popd || exit
 popd || exit
 
-# Extract headers into a tarball
-dpkg -x src/linux-headers-"${KERN_VERSION}${LOCALVERSION}_${KERN_VERSION}${DEB_SUFFIX}" .
+# Package headers into the same directory structure the old deb-pkg approach produced
+# (usr/src/linux-headers-<version><localversion>/{include,arch}).
+KERNEL_ARCH="${ARCH//x86_64/x86}"
+HEADERS_DIR="usr/src/linux-headers-${KERN_VERSION}${LOCALVERSION}"
+
+mkdir -p "${HEADERS_DIR}/arch"
+cp -a "src/linux-${KERN_VERSION}/include" "${HEADERS_DIR}/"
+cp -a "src/linux-${KERN_VERSION}/arch/${KERNEL_ARCH}" "${HEADERS_DIR}/arch/"
 
 # Remove broken symlinks
-find usr/src/linux-headers-"${KERN_VERSION}${LOCALVERSION}" -xtype l -exec rm {} +
-
-# Remove uneeded files to reduce size
-# Keep only:
-# - usr/src/linux-headers-x.x.x-pl/include
-# - usr/src/linux-headers-x.x.x-pl/arch/${ARCH}
-# This reduces the size by a little over 2x.
-rm -rf usr/share
-find usr/src/linux-headers-"${KERN_VERSION}${LOCALVERSION}" -maxdepth 1 -mindepth 1 ! -name include ! -name arch -type d \
-    -exec rm -rf {} +
-find usr/src/linux-headers-"${KERN_VERSION}${LOCALVERSION}"/arch -maxdepth 1 -mindepth 1 ! -name "${ARCH//x86_64/x86}" -type d -exec rm -rf {} +
+find "${HEADERS_DIR}" -xtype l -exec rm {} +
 
 tar zcf linux-headers-"${ARCH}"-"${KERN_VERSION}".tar.gz usr