On 2020-10-23, Mathieu Othacehe wrote:
>>> ice-9/boot-9.scm:1669:16: In procedure raise-exception:
>>> ERROR:
>>>   1. &i/o-filename: "/dev/disk/by-id/mmc-SDU64_0xbaf3002e"
>>
>> Thanks for testing. This is probably a regression in
>> "write-file-on-device" that fails to open this kind of files. I'll try
>> to reproduce it locally.
>
> This is because the O_EXCL flag was passed, which causes open to fail if
> the block device is mounted.
>
> The revised patch attached should fix it.

Yes, this patch fixes the issue for me.

Thanks!

live well,
  vagrant

> From 780327ebb0db74ca4cc43d26ba7cf945d64c7d30 Mon Sep 17 00:00:00 2001
> From: Mathieu Othacehe <othacehe@gnu.org>
> Date: Wed, 21 Oct 2020 10:42:50 +0200
> Subject: [PATCH] system: reconfigure: Use the disk-installer if provided.
>
> ---
>  gnu/build/bootloader.scm            |  4 ++--
>  gnu/tests/reconfigure.scm           |  4 +++-
>  guix/scripts/system/reconfigure.scm | 12 +++++++++---
>  3 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/gnu/build/bootloader.scm b/gnu/build/bootloader.scm
> index 5ec839f902..06a2c3ab76 100644
> --- a/gnu/build/bootloader.scm
> +++ b/gnu/build/bootloader.scm
> @@ -39,9 +39,9 @@
>        (let ((bv (get-bytevector-n input size)))
>          (call-with-port
>           (open-file-output-port device
> -                                (file-options no-truncate no-create)
> +                                (file-options no-truncate no-fail)
>                                  (buffer-mode block)
> -                                (native-transcoder))
> +                                (make-transcoder (latin-1-codec)))
>           (lambda (output)
>             (seek output offset SEEK_SET)
>             (put-bytevector output bv)))))))
> diff --git a/gnu/tests/reconfigure.scm b/gnu/tests/reconfigure.scm
> index 928a210a94..52beeef447 100644
> --- a/gnu/tests/reconfigure.scm
> +++ b/gnu/tests/reconfigure.scm
> @@ -260,7 +260,9 @@ bootloader's configuration file."
>       ;; test suite, the bootloader installer script is omitted. 'grub-install'
>       ;; would attempt to write directly to the virtual disk if the
>       ;; installation script were run.
> -     (test (install-bootloader-program #f #f bootcfg bootcfg-file #f "/")))))
> +     (test
> +      (install-bootloader-program #f #f #f bootcfg bootcfg-file #f "/")))))
> +
>  
>  (define %test-switch-to-system
>    (system-test
> diff --git a/guix/scripts/system/reconfigure.scm b/guix/scripts/system/reconfigure.scm
> index d89caf80fc..b1982b20d2 100644
> --- a/guix/scripts/system/reconfigure.scm
> +++ b/guix/scripts/system/reconfigure.scm
> @@ -204,7 +204,8 @@ services as defined by OS."
>  ;;; Bootloader configuration.
>  ;;;
>  
> -(define (install-bootloader-program installer bootloader-package bootcfg
> +(define (install-bootloader-program installer disk-installer
> +                                    bootloader-package bootcfg
>                                      bootcfg-file device target)
>    "Return an executable store item that, upon being evaluated, will install
>  BOOTCFG to BOOTCFG-FILE, a target file name, on DEVICE, a file system device,
> @@ -246,10 +247,12 @@ BOOTLOADER-PACKAGE."
>               ;; a broken installation.
>               (switch-symlinks new-gc-root #$bootcfg)
>               (install-boot-config #$bootcfg #$bootcfg-file #$target)
> -             (when #$installer
> +             (when (or #$installer #$disk-installer)
>                 (catch #t
>                   (lambda ()
> -                   (#$installer #$bootloader-package #$device #$target))
> +                   (if #$installer
> +                       (#$installer #$bootloader-package #$device #$target)
> +                       (#$disk-installer #$bootloader-package 0 #$device)))
>                   (lambda args
>                     (delete-file new-gc-root)
>                     (match args
> @@ -272,11 +275,14 @@ additional configurations specified by MENU-ENTRIES can be selected."
>    (let* ((bootloader (bootloader-configuration-bootloader configuration))
>           (installer (and run-installer?
>                           (bootloader-installer bootloader)))
> +         (disk-installer (and run-installer?
> +                              (bootloader-disk-image-installer bootloader)))
>           (package (bootloader-package bootloader))
>           (device (bootloader-configuration-target configuration))
>           (bootcfg-file (bootloader-configuration-file bootloader)))
>      (eval #~(parameterize ((current-warning-port (%make-void-port "w")))
>                (primitive-load #$(install-bootloader-program installer
> +                                                            disk-installer
>                                                              package
>                                                              bootcfg
>                                                              bootcfg-file
> -- 
> 2.28.0