reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/hare/scsi-devel.git/commit/?id=5ee9c143b806000467a489e080f5d0f7db3af48e
        git remote add hare-scsi-devel https://git.kernel.org/pub/scm/linux/kernel/git/hare/scsi-devel.git
        git fetch --no-tags hare-scsi-devel configfs-ns.v2
        git checkout 5ee9c143b806000467a489e080f5d0f7db3af48e

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/nvme/target/