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* Question on initrd and initramfs
@ 2012-09-27 16:57 Ezequiel Garcia
  2012-09-27 17:43 ` Autif Khan
  2012-09-28  0:58 ` Mulyadi Santosa
  0 siblings, 2 replies; 13+ messages in thread
From: Ezequiel Garcia @ 2012-09-27 16:57 UTC (permalink / raw)
  To: kernelnewbies

Hi,

This is *not* another question about initrd vs initramfs (I already
read Documentation/...).

That said, I'm doing some experiments with:
 * qemu
* a very small kernel
* busybox static-linked rootfs

I can create an initramfs using this:
$ cd initramfs
$ find . | cpio -H newc -o > ../initramfs.cpio

Then I use start qemu like this:
$ qemu -kernel bzImage -initrd initramfs.cpio

This works.

Now to my first question:
The kernel is compiled WITHOUT any fs driver... So how the f@#ck did
he mounted initramfs? How are the files formatted?

And second question:
I want to repeat the above procedure but using initrd instead of
initramfs, is this still supported?
I'd like to use romfs or squashfs... anyone knows how to create this
initrd and how to give it to qemulated kernel?

This seems trivial, but I spent all morning and had no luck... :-(

FWIW: My current kernel size (compressed) is around 500k!
This is the smaller kernel I managed to boot. It has nothing (not even /proc)
so it's pretty useless but at least it can run a shell :-)

The question I'm trying to answer is: how little can it be, while
still remaining useful?

Thanks!
Ezequiel.

^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2012-10-07  0:36 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-09-27 16:57 Question on initrd and initramfs Ezequiel Garcia
2012-09-27 17:43 ` Autif Khan
2012-09-27 18:44   ` Ezequiel Garcia
2012-09-28 10:53   ` Ezequiel Garcia
2012-09-28 11:11     ` Ezequiel Garcia
2012-09-28  0:58 ` Mulyadi Santosa
2012-09-28 10:56   ` Ezequiel Garcia
2012-09-29 17:27     ` Mulyadi Santosa
2012-09-29 17:39       ` Ezequiel Garcia
2012-09-29 18:10       ` Tobias Boege
2012-09-30  8:01         ` Mulyadi Santosa
2012-10-05 19:25           ` Ezequiel Garcia
2012-10-07  0:36             ` Mulyadi Santosa

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