[klibc] Reason for gen_init_cpio instead of just cpio?

[Kevin P. Fleming]

I've googled to try and find discussion of this topic but didn't see any results 
particularly interesting... Is there any particular reason the kernel has 
gen_init_cpio instead of just using cpio itself? I'm working on some changes 
that would involve just cpio-ing the entire usr/root subtree as the initramfs 
image (instead of gen_init_cpio having to know ahead of time what files to 
include), and am wondering why it wouldn't be just easier to use cpio itself.

If there's a good reason, I can certainly extend gen_init_cpio to do the 
tree-walk and build the initramfs that way.