reproduce (this is a W=1 build): git remote add tytso-ext4 https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git git fetch tytso-ext4 dev git checkout tytso-ext4/dev b4 shazam https://lore.kernel.org/r/20240326213823.528302-3-shikemeng@huaweicloud.com # 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 fs/