Use ramdisk to build latest kernel deb package for debian

build_kernel.sh

#!/bin/bash

if [[ $EUID -ne 0 ]]
then
   echo "This script must be run as root"
   exit 1
fi

if [[ $# -ne 1 ]]
then
    echo "need to specify kernel version"
    exit 1
fi

version=$1
VersionSeries=$(echo ${version} | cut -d. -f1)

# Download
url=https://cdn.kernel.org/pub/linux/kernel/v${VersionSeries}.x/linux-${version}.tar.xz

wget -S --spider ${url} 2>&1 | grep -q 'HTTP/1.1 200 OK'

if [[ $? == "1" ]]
then
    echo "Could not find kernel with url: ${url}"
    exit 1
fi

mkdir -p /tmp/ramdisk
# use 5GB ram as ramdisk
# building 4.18 kernel uses around 3.2GB
sudo mount -t tmpfs -o size=5G tmpfs /tmp/ramdisk
wget -O /tmp/ramdisk/linux-${version}.tar.xz ${url}
pushd /tmp/ramdisk
tar xf linux-${version}.tar.xz
cd linux-${version}
cp /boot/config-$(uname -r) ./.config
time make deb-pkg -j7