initrd or initramfs in k3.2.30/31

[dubi]

I am building kernel 3.2.30 or 3.2.31

I do not see initramfs (or initrd) in the output just: bzImage and modules

Is it necessary to have this file or the system can boot from bzImage alone .

my .config has :
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE=""

In past k3.. builds I recall there was an initrd file generated but I do not have anymore the .config from that build to examine .

unfortunately CONFIG_INITRAMFS_SOURCE= needs specify the directories which have the initramfs content and I do not have it now, unless it is part of the kernel sources somewhere . If so where ?

[hazel]

Building a kernel does not create an initrd. You have to do that separately. Your distro will have a script for doing it - it's usually called something like mkinitrd.

The kernel parameters that you have quoted are necessary so that the kernel can read an initrd when you have created one.