reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        git remote add xfs-linux https://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git
        git fetch xfs-linux for-next
        git checkout xfs-linux/for-next
        b4 shazam https://lore.kernel.org/r/20250227180813.1553404-9-john.g.garry@oracle.com
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-21 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-21 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/gpu/drm/clients/ fs/xfs/ kernel/cgroup/