02/02: doc: Document command-line options honored by the initrd.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit e90cf6c14a32472f013959f0b79b80888e6fa35c
Author: Ludovic Courtès <address@hidden>
Date:   Sat Jan 16 14:44:21 2016 +0100

    doc: Document command-line options honored by the initrd.
    
    * doc/guix.texi (Initial RAM Disk): Document kernel command-line
    options.
---
 doc/guix.texi |   44 ++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 44 insertions(+), 0 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index e583e8c..d055ae3 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -8842,6 +8842,50 @@ The @code{base-initrd} procedure also handles common use 
cases that
 involves using the system as a QEMU guest, or as a ``live'' system whose
 root file system is volatile.
 
+The initial RAM disk produced by @code{base-initrd} honors several
+options passed on the Linux kernel command line (that is, arguments
+passed @i{via} GRUB's @code{linux} command, or with QEMU's
address@hidden option), notably:
+
address@hidden @code
address@hidden address@hidden
+Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
+program, once it has mounted the root file system.
+
+GuixSD uses this option to yield control to a boot program that runs the
+service activation programs and then spawns address@hidden, the
+initialization system.
+
address@hidden address@hidden
+Mount @var{root} as the root file system.  @var{root} can be a device
+device name like @code{/dev/sda1}, a partition label, or a partition
+UUID.
+
address@hidden address@hidden
+Have @file{/run/booted-system} and @file{/run/current-system} point to
address@hidden
+
address@hidden address@hidden@dots{}
address@hidden module, black-listing
address@hidden black list, of kernel modules
+Instruct the initial RAM disk as well as the @command{modprobe} command
+(from the kmod package) to refuse to load @var{modules}.  @var{modules}
+must be a comma-separated list of module names---e.g.,
address@hidden,9pnet}.
+
address@hidden --repl
+Start a read-eval-print loop (REPL) from the initial RAM disk before it
+tries to load kernel modules and to mount the root file system.  Our
+marketing team calls it @dfn{boot-to-Guile}.  The Schemer in you will
+love it.  @xref{Using Guile Interactively,,, guile, GNU Guile Reference
+Manual}, for more information on Guile's REPL.
+
address@hidden table
+
+Now that you know all the features that initial RAM disks produced by
address@hidden provide, here is how to use it and customize it
+further.
+
 @deffn {Monadic Procedure} base-initrd @var{file-systems} @
        [#:qemu-networking? #f] [#:virtio? #f] [#:volatile-root? #f] @
        [#:extra-modules '()] [#:mapped-devices '()]