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From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Resolving Linux module dependencies
Date: Fri, 28 Nov 2014 08:58:50 +0100
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To: Guix-devel <guix-devel@gnu.org>

In light of <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=3D19190#23>, I
realized that the na=C3=AFve handling of kernel modules (=C3=A0 la =E2=80=
=98insmod=E2=80=99) in
the initrd and at boot time did not scale: one had to specify the
dependencies of the modules to be loaded from the initrd and do so in
topological order.

For a moment I contemplated the idea of writing libkmod bindings to do
that, and then realized that using Andy=E2=80=99s ELF parser would get us t=
here
more quickly.

So the recent commits import the ELF parser from Guile 2.1, then use it
to obtain module dependency information in (gnu build linux-boot), use
that dependency information to copy the closure of the user-specified
modules to the initrd, and finally load the closure of the
user-specified modules (=C3=A0 la =E2=80=98modprobe=E2=80=99.)

Comments & bug reports welcome!

I was happy to see we could get things done this quickly thanks to the
ELF parser.  :-)

Ludo=E2=80=99.