got this with my current config. Along with other misc gcc 3 warnings. Compiling with gcc (GCC) 3.3 (Debian) ld -m elf_i386 -T arch/i386/vmlinux.lds.s arch/i386/kernel/head.o arch/i386/kernel/init_task.o init/built-in.o --start-group usr/built-in.o arch/i386/kernel/built-in.o arch/i386/mm/built-in.o arch/i386/mach-default/built-in.o kernel/built-in.o mm/built-in.o fs/built-in.o ipc/built-in.o security/built-in.o crypto/built-in.o lib/lib.a arch/i386/lib/lib.a drivers/built-in.o sound/built-in.o arch/i386/pci/built-in.o net/built-in.o --end-group -o vmlinux kernel/built-in.o(.text+0x1708e): In function `free_module': : undefined reference to `percpu_modfree' kernel/built-in.o(.text+0x17873): In function `load_module': : undefined reference to `find_pcpusec' kernel/built-in.o(.text+0x179a9): In function `load_module': : undefined reference to `percpu_modalloc' kernel/built-in.o(.text+0x17c52): In function `load_module': : undefined reference to `percpu_modcopy' kernel/built-in.o(.text+0x17d3d): In function `load_module': : undefined reference to `percpu_modfree' make: *** [vmlinux] Error 1 i've attached my config