reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git/commit/?id=c779b2a64b9d34cf93dc39b022330262e947369b
        git remote add jarkko-tpmdd https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git
        git fetch --no-tags jarkko-tpmdd tpm2-session
        git checkout c779b2a64b9d34cf93dc39b022330262e947369b

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash security/keys/trusted-keys/