reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?id=d05755164e0488102f7c1ca8333a0c4bb20099a2
        git remote add arm-platforms https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git
        git fetch --no-tags arm-platforms pci/xgene-fixes
        git checkout d05755164e0488102f7c1ca8333a0c4bb20099a2
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um olddefconfig
        make W=1 O=build_dir ARCH=um SHELL=/bin/bash drivers/pci/controller/