reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-46-gadceff0a-dirty
        # https://github.com/intel-lab-lkp/linux/commit/b2e5852793b6eb4da1fba9cac363421858b62a95
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Mina-Almasry/vsock-virtio-use-skb_frag_-helpers/20231222-164637
        git checkout b2e5852793b6eb4da1fba9cac363421858b62a95
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=x86_64 olddefconfig
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=x86_64 SHELL=/bin/bash net/core/ net/ethtool/