reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/sean-jc/linux/commit/13d55dfeb2036ae6cc08c9ddc0119273c9df007e
        git remote add sean-jc https://github.com/sean-jc/linux
        git fetch --no-tags sean-jc rev/userfault
        git checkout 13d55dfeb2036ae6cc08c9ddc0119273c9df007e
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash arch/arm64/