Не собирается ядро без поддержки initrd. Обваливается с такой ошибкой -
................................................
  MODPOST vmlinux.o
WARNING: modpost: Found 1 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
  GEN     .version
  CHK     include/generated/compile.h
  UPD     include/generated/compile.h
  CC      init/version.o
  LD      init/built-in.o
  LD      .tmp_vmlinux1
init/built-in.o: In function `kernel_init':
/usr/src/linux/init/main.c:852: undefined reference to `populate_rootfs_wait'
arch/x86/built-in.o: In function `call_usermodehelper_fns':
/usr/src/linux/include/linux/kmod.h:96: undefined reference to `populate_rootfs_wait'
kernel/built-in.o: In function `call_usermodehelper_fns':
/usr/src/linux/include/linux/kmod.h:96: undefined reference to `populate_rootfs_wait'
fs/built-in.o: In function `call_usermodehelper_fns':
/usr/src/linux/include/linux/kmod.h:96: undefined reference to `populate_rootfs_wait'
security/built-in.o: In function `call_usermodehelper_fns':
/usr/src/linux/include/linux/kmod.h:96: undefined reference to `populate_rootfs_wait'
lib/lib.a(kobject_uevent.o):/usr/src/linux/include/linux/kmod.h:96: more undefined references to `populate_rootfs_wait' follow
make: *** [.tmp_vmlinux1] Error 1
root@ubuntu-test2:/usr/src/linux#

Ядро монолитное, поддержка фс и sata включены...

Система Ubuntu 12.04
linux-source-3.2.0               3.2.0-31.50                Linux kernel source for version 3.2.0 with Ubuntu patches