Re: Initializing a 64bit system using guix on a 32bit OS

[Mark H Weaver]

address@hidden (Ludovic Courtès) writes:

> Alex Kost <address@hidden> skribis:
>
>> Hello, I have Guix installed on a 32-bit "ArchLinux", and I use the
>> following command to “deploy” a 64-bit GuixSD:
>>
>> $ guix system init --no-grub --system=x86_64-linux my-os-config.scm /mnt/guix
>>
>> However, eventually it fails with the following output:
>>
>> ...
>> downloading `/gnu/store/qf803k3npvn8632vssc4g3zp0s5klghv-modprobe'
>> from
>> `http://hydra.gnu.org/nar/qf803k3npvn8632vssc4g3zp0s5klghv-modprobe'
>> (0.0 MiB installed)...
>> http://hydra.gnu.org/nar/qf803k3npvn8632vssc4g3zp0s5klghv-modprobe      0.5 
>> KiB transferredkilling process 18626
>> guix system: error: build failed: a `x86_64-linux' is required to build 
>> `/gnu/store/zckxg5v0pdxb22kyl6jrzawj1wwrfjby-locale.drv', but I am a 
>> `i686-linux'
>
> It works as long as there are substitutes available, but some
> derivations are not substitutable, as you noticed, and since an i686
> host cannot run x86_64 code, you get this error.
>
>> So I'm wondering is there a way to init a 64-bit system from a 32-bit
>> one or perhaps it's just not possible?
>
> It actually is possible, but a little bit trickier.  Mark did it a few
> weeks ago, though in a slightly different context.  The following should
> work:
>
>   1. Install an i686 GuixSD, simply with ‘guix system init’, but use an
>      x86_64 kernel.  To do that, you need to explicitly ask for an
>      x86_64 kernel and Guix (so that the daemon accepts to build x86_64
>      things) in the OS config:
>
>        (define linux-libre-x86_64
>          (package (inherit linux-libre)
>            (arguments `(#:system "x86_64-linux"
>                         ,@(package-arguments linux-libre)))))

I think this is not sufficient, because it would still use the kernel
config for i686.  Here's what I used for the kernel:

>From 1f6f6c9cfecfc5bf72bdfc97caf7247090c0e1f3 Mon Sep 17 00:00:00 2001
From: Mark H Weaver <address@hidden>
Date: Mon, 20 Apr 2015 23:51:45 -0400
Subject: [PATCH] LOCAL_ONLY: gnu: Add linux-libre-64.

---
 gnu/packages/linux.scm | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/gnu/packages/linux.scm b/gnu/packages/linux.scm
index 26e9aa9..c42919d 100644
--- a/gnu/packages/linux.scm
+++ b/gnu/packages/linux.scm
@@ -64,6 +64,7 @@
   #:use-module (guix build-system cmake)
   #:use-module (guix build-system python)
   #:use-module (guix build-system trivial)
+  #:use-module ((guix build utils) #:select (alist-replace))
   #:use-module (srfi srfi-26)
   #:use-module (ice-9 match))
 
@@ -308,6 +309,15 @@ It has been modified to remove all non-free binary blobs.")
     (license gpl2)
     (home-page "http://www.gnu.org/software/linux-libre/";))))
 
+(define linux-libre-64
+  (package (inherit linux-libre)
+    (arguments
+     `(#:system "x86_64-linux"
+       ,@(package-arguments linux-libre)))
+    (native-inputs
+     (alist-replace "kconfig" (list (kernel-config "x86_64-linux"))
+                    (package-native-inputs linux-libre)))))
+
 
 ;;;
 ;;; Pluggable authentication modules (PAM).
-- 
2.2.1

    Mark