Getting started with mdev
rob at landley.net
Thu Dec 14 23:09:41 UTC 2006
On Thursday 14 December 2006 5:39 pm, Trevor Harmon wrote:
> On Dec 14, 2006, at 2:04 PM, Rob Landley wrote:
> > My fault. What do you need?
> A simple docs/mdev.txt file summarizing the key points mentioned in
> this thread would have helped a lot.
> > You need /dev/console in your initramfs. This is a funky kernel
> > thing. I
> > don't know why they don't just create it, ask linux-kernel. The
> > default
> > initramfs has one.
> What is the "default" initramfs?
If you don't supply an initramfs, you get one with three
entries: /dev, /dev/console, and /root.
Why that? Because that was the example output from
scripts/gen_initramfs_list.sh when you ran it with no arguments, which the
kernel was doing for a dozen or so versions when you hadn't specified an
initramfs location in the kernel's .config. By the time anybody noticed, the
kernel had developed a dependency on the /dev/console entry in there. :)
These days, gen_initramfs_list.sh produces this default .config file when you
give it the -d option, and outputs nothing when you run it with no arguments.
This is considered an improvement.
As far as I know, nothing depends on the /root entry. It was just part of the
example config file. (You need the /dev entry to have a directory to
put /dev/console in.)
"Perfection is reached, not when there is no longer anything to add, but
when there is no longer anything to take away." - Antoine de Saint-Exupery
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