Build mainline kernel on Ubuntu 22.04

build.sh

#!/bin/bash
set -e
KERNEL_VER="6.12"

sudo apt install -y git build-essential fakeroot libncurses5-dev libssl-dev ccache dpkg-dev libelf-dev debhelper-compat libncurses-dev gawk flex bison openssl libssl-dev dkms libelf-dev libudev-dev libpci-dev libiberty-dev autoconf llvm

# Clone the kernel
mkdir -p kernelbuild
cd kernelbuild
if [ ! -d "linux-stable" ] ; then
    git clone --depth=1 -b linux-$KERNEL_VER.y git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
    cd linux-stable
else
    cd linux-stable
    git pull
fi

# Build custom kernel
cp /boot/config-`uname -r` .config # copy config from current kernel
yes '' | make oldconfig

# Remove keys
sed -i 's/CONFIG_SYSTEM_TRUSTED_KEYS=.*/CONFIG_SYSTEM_TRUSTED_KEYS=""/' .config
sed -i 's/CONFIG_SYSTEM_TRUSTED_KEYRING=.*/CONFIG_SYSTEM_TRUSTED_KEYRING=""/' .config
sed -i 's/CONFIG_SYSTEM_REVOCATION_KEYS=.*/CONFIG_SYSTEM_REVOCATION_KEYS=""/' .config

make clean
make -j $(getconf _NPROCESSORS_ONLN) deb-pkg LOCALVERSION=-custom

# Install new kernel
# sudo dpkg -i ~/kernelbuild/linux-*.deb