reproduce (this is a W=1 build):
        # https://github.com/jcmvbkbc/linux-xtensa/commit/45c61e979c95928370efa03921af750bcc394f18
        git remote add jcmvbkbc-xtensa https://github.com/jcmvbkbc/linux-xtensa
        git fetch --no-tags jcmvbkbc-xtensa xtensa-6.11-esp32
        git checkout 45c61e979c95928370efa03921af750bcc394f18
        # 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 kernel/events/