reproduce (this is a W=1 build):
        git remote add kdave https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git
        git fetch kdave for-next
        git checkout kdave/for-next
        b4 shazam https://lore.kernel.org/r/50e41f048f26b5b58f55b25c045e5dfe94a8dcfd.1745443508.git.wqu@suse.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/btrfs/