reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/commit/?id=16adb0d62633d31709c26ea63ab9de6ec1bbdf4e
        git remote add mark https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git
        git fetch --no-tags mark sched/preempt-dynamic-optimizations
        git checkout 16adb0d62633d31709c26ea63ab9de6ec1bbdf4e

        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.4.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=loongarch olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.4.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash kernel/sched/