Subject: Re: representation of persistent device status, was Re: devfs, was Re: ptyfs...
To: Jonathan Stone <>
From: Eric Haszlakiewicz <>
List: tech-kern
Date: 11/27/2004 02:29:31
On Fri, Nov 26, 2004 at 01:23:08PM -0800, Jonathan Stone wrote:
> As someone -- perhaps Daniel Carosone -- guessed at: think of an
> hardened embedded device (not unlike the hardened routers Thor
> sometimes talks about) The kind of embedded-device where perhaps you
> already have filesystems set up as either executable, or non-writable,
> or both.  (For a second example, think of a chroot jail in such an
> appliance.)

	Could you explain this a bit more please.  I'm not quite understanding
how this requires an old-style device node.  I'm also getting stuck on
what you mean by "already have filesystems set up".  As I understand it,
regardless of whether you're running on an embedded device or not, you
still go through the process of:
	kernel boots
	root is mounted
	rc.d scripts mount other filesystems
	other programs run, possibly in a chroot
i.e. there aren't any filesystems set up until the startup scripts do
something.  It seems to me that those startup scripts could also mount
the 1 + n-for-every-chroot-environment devfs's also.

	Of course, this is more complicated than just having the limited
number of necessary device nodes already present in the chroot environments.
(two steps: setup chroot /dev & setup fstab, vs just the first)
I can see how that argument has some merit, but it doesn't sound like
a complete non-starter to me.