Re: updating kernel to 2.6.13-rc1 from 2.6.12 + CONFIG_DEVFS_FS + empty /dev

[eric.valette@free.fr]

Quoting Greg KH <greg@kroah.com>:

> On Wed, Jun 29, 2005 at 11:03:56PM +0200, Eric Valette wrote:
> > For years now my /dev has been empty. When upgrading to 2.6.13-rc1 from
> > 2.6.12, and updating my kernel config file via "make oldconfig" I got no
> > visible warning about CONFIG_DEVFS_FS options being set (or at least did
> > no see it).
>
> devfs has been marked OBSOLETE for a year now.  It has also been
> documented as going away.  Because of this, you should not have been
> supprised at all.

I knew it! I just the announce for 2.6.13-rc1 did not contain this fact and I
did not realize booting this new kernel will fail on my machine which is bad for
a stable serie.


> What are the speed differences that you see?  I've tested it and on a
> slow old laptop, with a lot of devices, udev only takes 2 seconds to
> initialize the whole device tree.  If you put it in initramfs, it will
> take no additional time, as it will operate on all of the hotplug events
> as they happen.  Can't get faster than "nothing" :)


If I already have every device in /dev, I do not need udev and yes it is fast
:-) This is exactly what I did to boot my system again. Just via devfs, I do
not need an initial filesystem nor need anything in user space to boot a full
system which I like.


-- eric