bug#22274: GuixSD resets hardware clock (on Lenovo x200 with libreboot)

[Christopher Allan Webber <cwebber@dustycloud.org>]

Mark H Weaver writes:

> Very strange.  FWIW, I've used Libreboot X60 and X200 laptops running
> GuixSD quite extensively -- they are my primary development machines --
> and I've never seen anything like this.
>
> One possibility that comes to mind is that perhaps your hardware clock
> battery is dead, and that sometimes Debian is able to hide that fact by
> setting the date via NTP or something.  Can you try running "hwclock -r"
> after a cold boot into Debian and see what it says?

Yes it isn't the battery.  I've also verified that this happens on my
friend Aeva's minifree x200 w/ Libreboot + Guix.  More on that in my
next email.

>> Any idea what could be causing this?  I noticed that if I rebooted it
>> at the time that it asked me for a passphrase to decrypt /home/ that it
>> didn't reset the clock, though maybe I should test that again.
>
> If you're sharing /home between Debian and GuixSD, I wonder if going
> back and forth between two different versions of GNOME while sharing the
> data in dot-files/directories is causing a problem?
>
> This in turn makes me wonder if the clock is truly being reset during
> the GuixSD boot process, or if it might be happening during login to
> your desktop environment.  Please try the following:
>
> * Cold boot into Debian.
> * Set the hardware clock (hwclock -w).
> * Read the hardware clock to verify that it works (hwclock -r).
> * Reboot into GuixSD.
> * Log in to a text console as root and check both the system clock
>   (date) and the hardware clock (hwclock -r).
>
>      Thanks,
>        Mark

I've done this and I ran into problems still.  However, I think I
figured out the source of them... I suspect there were two problems.
I'll detail in my reply to Ludovic.