reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git/commit/?id=9ac3dc495a43f5fe6c0c4557d80ecd11d6cf3351
        git remote add trace https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
        git fetch --no-tags trace unwind/sframe-test
        git checkout 9ac3dc495a43f5fe6c0c4557d80ecd11d6cf3351
        # 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