reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/brauner/linux/commit/f15a9ae05a7144ff3bc3ce58622dfb7043acb138
        git remote add brauner-github https://github.com/brauner/linux.git
        git fetch --no-tags brauner-github work.freeze
        git checkout f15a9ae05a7144ff3bc3ce58622dfb7043acb138
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-8.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-8.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash fs/gfs2/