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

[Mark H Weaver <mhw@netris.org>]

Christopher Allan Webber <cwebber@dustycloud.org> writes:

> I recently installed GuixSD on the laptop I got fresh from Minifree.  I
> was happy to see how much worked, but I've noticed a bug that occurs in
> GuixSD but not in Debian.
>
> In Debian I can set the hardware clock (with `hwclock -w`) and if I
> reboot back into Debian again, I still have the same hardware clock.
>
> If I reboot into GuixSD, at some point in the boot process it resets my
> hardware clock to 1970!  If I reboot into Debian again after that, it's
> 1970 there also.

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?

> 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