bug#70051: guix system hangs on boot with LUKS /home partition

bug#70051: guix system hangs on boot with LUKS /home partition

[Fulbert]

Hello,

Up to guix 9b84b36, my system was properly booting with a LUKS2 partition
mounted on /home. Starting with guix d5f857a (22 mar 2024), the boot hangs on
the same system using the same configuration.scm file. The only way out I found
when it hangs is hardware shutdown. There are no avaible console nor ssh server
started to help troubleshoot and there is nothing written to /var/log/messages
when it hangs.

I have tried to transfer my /home data to a brand new LUKS1 partition, (as well
as removing pointers to the old LUKS2 partition in my config.scm, of course) and
the problem remains exactly the same, including those error messages (obtained with
a video capture of the screen at boot, after removing 'quiet' from the kernel
command line in grub) :

#+begin_src boot
shepherd[1]: Starting service device-mapping-luks-homes...
shepherd[1]: Service device-mapping-luks-homes failed to start.
shepherd[1]: Exception caught while while starting device-mapping-luks-homes: (unbound-variable #f "Unbound variable: "S" (bytevector?) #f)
#+end_src

Maybe it's worth mentionning that I have then tried one configuration of the
'mapped-device' with 'luks-device-mapping' and another one with
'luks-device-mapping-with-options #:keyfile "/…"'. I also tried one
configuration with the 'source' declared in plain "/dev/..." and another one
declared with the luks '(uuid "…")', but this didnt change anything to the
"symptoms".

So, although I have learned in the process that LUKS2 is not yet fully
supported in guix, this problem also prevents booting using a LUKS1 /home
partition in my case.

Transfering the /home data to a clear (unencrypted) partition is my current
workaround to this problem.

Below is the configuration that has worked for several weeks, if not months, using my LUKS2 /home :

  (mapped-devices
    (list
      (mapped-device
        (source (uuid "<the uuid>"))
        (target "luks-homes")
        (type luks-device-mapping))))

  (file-systems
    (append
      (list
        […]
        (file-system (mount-point "/home")
                     (device (file-system-label "luks-homes"))
                     (type "ext4")
                     (dependencies mapped-devices))
        […]

Best regards and thanks for guix !

bug#70051:

[Fulbert]

… And I forgot to mention that, when the boot hangs, shepherd still responds to ctrl-alt-del by closing some services and then the system hangs with hardware button shutdown as last resort.

bug#70051:

[Fulbert]

And I also forgot to mention *sigh* that I am not the only one affected
by this problem. See : https://lists.gnu.org/archive/html/help-guix/2024-03/msg00152.html

bug#70051: same

[Lilah Tascheter]

yep I got the same issue too. but, in my case, I have an encrypted root
with three other encrypted partitions, none of them my home. initrd
decryption succeeds, but shepherd device-mapper services fail as usual

bug#70051: [PATCH] gnu: open-luks-device: Fix unbound variables.

[aurtzy]

It seems like `use-modules' never actually worked due to the way it is eval'd
by the Shepherd, and was only apparent after a change that prevented other
module imports from leaking into the namespace.  This is fixed by using direct
references instead.

* gnu/system/mapped-devices.scm (open-luks-device): Use direct references for
variables from other modules.

Fixes: https://issues.guix.gnu.org/70051

Change-Id: I993798e161c4b4fca6e8a4f14eea5042b184ebc9
---

Hi!

I encountered this issue as well, and think I've figured out what was
happening: `use-modules' appears to not work due to the way g-expressions are
evaluated by Shepherd, so after services became properly isolated in their own
modules, the variable references became no longer available.  There's a
comment further down in the file that seems to confirm this ("XXX: We're not
at the top level here...").

Can anyone confirm this patch works for them too?

Cheers,

aurtzy

 gnu/system/mapped-devices.scm | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/gnu/system/mapped-devices.scm b/gnu/system/mapped-devices.scm
index c19a818453..e46e2c7954 100644
--- a/gnu/system/mapped-devices.scm
+++ b/gnu/system/mapped-devices.scm
@@ -201,14 +201,12 @@ (define* (open-luks-device source targets #:key key-file)
        #~(let ((source #$(if (uuid? source)
                              (uuid-bytevector source)
                              source))
-               (keyfile #$key-file))
-           ;; XXX: 'use-modules' should be at the top level.
-           (use-modules (rnrs bytevectors) ;bytevector?
-                        ((gnu build file-systems)
-                         #:select (find-partition-by-luks-uuid
-                                   system*/tty))
-                        ((guix build utils) #:select (mkdir-p)))
-
+               (keyfile #$key-file)
+               (bytevector? (@ (rnrs bytevectors) bytevector?))
+               (find-partition-by-luks-uuid (@ (gnu build file-systems)
+                                               find-partition-by-luks-uuid))
+               (system*/tty (@ (gnu build file-systems) system*/tty))
+               (mkdir-p (@ (guix build utils) mkdir-p)))
            ;; Create '/run/cryptsetup/' if it does not exist, as device locking
            ;; is mandatory for LUKS2.
            (mkdir-p "/run/cryptsetup/")

base-commit: 6e2db85ca83528199a46b002d2592bd4bef017c8
-- 
2.41.0

bug#70051: [PATCH] gnu: open-luks-device: Fix unbound variables.

[Remco van 't Veer]

2024/04/02, aurtzy:

> Can anyone confirm this patch works for them too?

Yes, it does.

Cheers,
Remco

bug#70051: guix system hangs on boot with LUKS /home partition

[Adrien 'neox' Bourmault]

I can confirm aurtzy's patch works (just tested on top of
7af70efd7633b0d70091762cf43ce01a86176e8e)

bug#70051: (no subject)

[Fulbert]

guix pull + reconfigure worked for me as well.

Thank you verry much.