The switch_root shell script did not work with bash-4.0-2, because
"exec" gets the real path of the executable which is then
"/sysroot/lib/ld-linux.so.2" instread of "./lib/ld-linux.so.2".
Also the required chroot binary might live in /usr/bin, which can
be mounted later.
Here is the switch_root code from nash, which can be stripped down
further, but which works.
>From f1b1e4f8694104f007e4483c36b0bf40a5760167 Mon Sep 17 00:00:00 2001
From: Harald Hoyer <harald-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Date: Wed, 4 Mar 2009 13:41:07 +0100
Subject: [PATCH] replace switch_root shell script with binary
The switch_root shell script did not work with bash-4.0-2, because
"exec" gets the real path of the executable which is then
"/sysroot/lib/ld-linux.so.2" instead of "./lib/ld-linux.so.2".
Also the required chroot binary might live in /usr/bin, which can
be mounted later.
Here is the switch_root code from nash, which can be stripped down
further, but which works.
This should arguably be done by importing the udev git repo as a submodule,
but I am too lazy to figure out how to do that right now.
I suppose this could also be done by rewriting the 95udev-rules.sh module
for each distribution, but that is something best left to the distro
maintainers once we acheive some sort of widespread adoption. Until then,
stealing rules from upstream udev seems like the most portable solution.
They are not needed to boot with dracut, so away they go.
Also rewrite inst_rules to automatically search likely rule locations when
installing udev rules.
This patch series aims to make dracut more distro-independent. It includes
some of the functionality that Seewer Philippe posted to the list to make
dracut work on Ubuntu.
depmod does not create these files on all distros (Debian, specifically),
so modify instmods to use pathname components and find to do what we want.
As a bonus, this removes the special-case for =ata.
When handling links sometimes one readlink isn't enough. Dracut doesn't
need to clone a whole link series, so just use readlink -f
--
dracut-functions | 8 +++-----
1 files changed, 3 insertions(+), 5 deletions(-)
On some systems with newer or unpatched bash versions the whole right
portion of =~ is considered part of the regex. Means we need to get rid
of enclosing ''.
This patch fixes this.
--
dracut-functions | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
find_binary inside dracut-functions always succeeds. Independent of
whether the file actually exists or not.
This patch fixes this.
And since we're using the function not only to find binaries at little
enhancement there shouldn't be that bad either.
--
dracut-functions | 21 ++++++++++++++++-----
1 files changed, 16 insertions(+), 5 deletions(-)
rules, hooks and modules are installed in $(DESTDIR)/usr/libexec/dracut/
instead of their corresponding sub-directories.
This patch fixes this.
--
Makefile | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
All modules now live in a subdirectory /modules.d. Each module is
self-contained -- it should contain everything that it will install
on the initrd. All modules must include a script named install, which
will be sourced by dracut. This script should do the actual file installation
using inst methods. The moddir variable will point to the full path to the
module dracut is currently working on.
As usual, this patch series applies on top of my previous patch series,
and is available as normalize-modules from http://git.fnordovax.org/dracut.
Static interfaces are still configured on the fly as we add them, but
discussions on the mailing list have suggested that we need to have finer
control over bringing up dhcp interfaces.
The default hook just runs all the requested dhclients in parallel and waits
for them to all return. If you need something more complicated than this, or
need to have more control over bringing interfaces up, you will probably need
to override some stuff in the 40network hook.
Provided that you are configuring them via DHCP. RARP, BOOTP, and static
configuration are not written yet.
Also, adding nic drivers really bloats the initrd.
I am looking for feedback on these patches from people who actually implement
booting over the network. This patch series does not include support for that
yet -- you will not find nfsroot= handling, or booting to a fs supplied by
dhcp yet. I do want to make it as easy as possible to add support for booting
over the network, as well as making it easy for people to customize things to
meet their site requirements.
This patch series is also available as the network-configurability branch at
http://git.fnordovax.org/dracut. It may be rebased without warning to keep
it in sync with the rest of dracut.
If the last character in the argument to search for is "=", then
getarg will echo all the text after the = as well as returning 0 or 1 depending
on whether or not the arg is found.
Otherwise, getarg will jsut return 0 if the exact test of the argument is found,
1 otherwise.
We now have mount hooks. They are sourced in an infinite loop until one of
them actually mounts the real root filesystem.
This makes it easier to add support for arbitrarily complex schemes to find
the root filesystem without having to patch the init script.
This patch series is also avaialble ass the hookify-finding-root branch at
http://git.fnordovax.org/dracut
Add some additional manglage to ensure that stdin/stdout is always pointing
the right thing. A more elegant way of doing this would be much appreciated
If exec fails, then the shell will die unless the next command
is part of a command list. So, exec $whatever || onoes is the way to go
There are also some minor cleanups that were leftovers from splitting
out switch_root in its current form.
This supercedes my previous switch_root patches, and applies on top of davej's
repo at git.kernel.org.
Nash is gone. In its place we have a reasonable switch_root implementation.
Of course, this switch_root is written in some rather hideous shell script,
and relies on some rather dodgy hacks. Rewriting in C would help things out.
However, it should be distro-independent, and it gets the job done.
Modules are now responsible for loading their hooks into the initrd.
This should be all the structure we need to make it easy for things
to integrate with dracut -- now to document and test it all.
We can use sh -c to accomplish the same goal
Also move cat back on to the list of debugging tools -- all the files we were
using it on in the initrd can use read to accomplish the same goal.
This replaces the eu-readelf and ld-linux.so.2 hackery.
As a bonus it will keep working if we (for some bizzare reason) need
to load a non-elf executable or shared library on the initrd.
This ensures that scripts will ahve their interpreter isntalled before
they get installed.
Also included a minor fixup that skips library checking if the binary
we are testing is already installed.
Harald Hoyer