Dear maintainers,

since upgrading to systemd 239-6, my systems stops during startup, at a text
mode login prompt. Switching to other consoles with alt+ctrl+F1-8 gives no
graphical manager.

As soon as i log in as root, the system continues starting up and goes to the
graphical login manager (of kde).

In the syslog entry below, i log in as root at 07:51:58 ; before that nothing
happens (apart from timesyncd noise). I tried this several times and it is
reproducible: root login in text mode is mandatory for systemd to finish
startup.

(Note that the text login is not an "emergency" login after a crash).

Best,

Ara

Am 20.07.2018 um 08:31 schrieb Ara Keary:

Is is sufficient if you simply wiggle the mouse or type random
characters for a while?

You might have a problem of not having enough entropy. There was a
recent kernel change in that regard.
https://lists.debian.org/debian-user/2018/05/msg00599.html
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=898092

Hi,
continues after enough entropy is created,
thanks,

best,

Ara

Am 20.07.2018 um 10:29 schrieb Ara Keary:

Ok, thanks for confirming. Are you using kdm or sddm?
Is this a virtual machine?

I'm using sddm, and booting the system normally (not on a virtual machine).

Best,
Ara

Am 20.07.2018 um 10:44 schrieb Ara Keary:

I'm going to reassign this issue to sddm and merge it with the existing
bug report.

VMs are typically more prone to have low entropy during bootup and there
are some mitigations for that (like installing something like haveged or
using virtio rng).

Regards,
Michael

Maxy (KDE/sddm maintainer) just suggested me to use haveged to workaround the
issue.

From the Qt/sddm code this would certainly not affect security, as the problem
lies in a hash structure used in the code. I can not vouch for other stuff in
the machine.

I have not seen this bug so far, but if any of you can still reproduce it you
might want to give this a try.

Cheers, Lisandro.

Hi,
i confirm that installing haveged solves the issue (no need anymore to
produce hand-made entropy at startup)
best,
Ara

This has happened so far:

From the Debian side maxy added haveged as a sddm recommendation and as a
workaround.

From the Qt side Thiago from upstream is trying to determine what changed in
the kernel side, as this clearly started to happen with 4.16 and got worse
with 4.17.

Ben, linux maintainers: if you could give us a hand to determine what changed
from the kernel side it would be much much appreciated. If we find that there
are valid changes then we might have an opportunity to make Qt upstreams
reconsider the issue.

Cheers, Lisandro.

CVE-2018-1108 was fixed in the kernel.

Ben.

Thanks Ben!!!!