Subject: Re: bug#35509: Stopping gdm-service results in an unresponsive system

From: Timothy Sample <[email-masked]>
Date: Wed, 01 May 2019 08:36:46 -0400

Hi Mark,

Mark H Weaver <[email-masked]> writes:

> On my x86_64-linux system running the Guix system, when I include
> gdm-service in my system services, 'herd stop xorg-server' results in a
> state where I seemingly cannot recover except by rebooting.  I'm left in
> what appears to be an empty Linux text console with a cursor in the top
> left corner, but the keyboard is unresponsive, and I'm not able to
> switch VTs.  Perhaps there is some SysRq key combination that could be
> used to recover, but I haven't yet tried.

This has been an issue with GDM since I started working on it.  IIRC,
it’s not entirely deterministic (but it fails most of the time).  I
don’t have any leads on this yet.

> Since I prefer to use Wayland, and would rather not have a separate Xorg
> session running that I never use, this means that currently I must avoid
> using 'gdm-service' entirely.

Yes.  The service does not currently support Wayland.  I believe that
Wayland support will require a few modifications to GDM itself.  At
least, we ended up modifying the X session startup a little bit, and I
would guess that the Wayland session startup would need similar changes.

> Note that this is on a system running fairly recent 'master', but before
> 'staging' was merged.  I'll try again and report back after I've
> finished rebuilding my post-staging-merge system.

Unfortunately, I wouldn’t expect the changes from staging to help here.

-- Tim