HiDPI scaling does not hold across reboot in a virtual machine

[Sébastien Taylor]

Running Ubuntu 17.10 Beta (updated as of 29 Sept 2017) on Parallels Desktop 13. When changing the HiDPI scaling to 200% everything looks good, but on restart the settings are reset to 100%.
---
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
DisplayManager: gdm3
DistroRelease: Ubuntu 18.04
GsettingsChanges:
 b'org.gnome.shell' b'enabled-extensions' b"['<email address hidden>']"
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
InstallationDate: Installed on 2018-05-26 (0 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
NonfreeKernelModules: prl_fs_freeze prl_fs prl_eth prl_tg
Package: gnome-shell 3.28.1-0ubuntu2
PackageArchitecture: amd64
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Tags: bionic
Uname: Linux 4.15.0-20-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True

[Sebastien Bacher (seb128)]

could be the same as bug #1716341

[Sébastien Taylor (sebastient)]

Curious if this is a one off or being consistently observed. Quite annoying in my setup since the VM gets powered on/off a fair bit and the setting refuses to stick.

[Sebastien Bacher (seb128)]

Is that still an issue with the current versions?

[John Wang (johnwang)]

Yes, same problem using the final 17.10 release ISO freshly installed as a guest OS under Parallels Desktop 13 on a MacBook Pro host. The default session it logs me into uses X.org instead of Wayland for some reason. My host machine's native resolution is 2880x1800 (but it's detected by Artful as 3360x2100, although that's also the same resolution my old Zesty VM Unity session mis-detected it as).

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Sébastien Taylor (sebastient)]

Didn't think it needed another bug report, maybe it does, but as of today the option has simply disappeared...

[John Wang (johnwang)]

I confirm #6. First, as I have to do every time I boot into my Ubuntu 17.10 VM under Parallels 13, I went to Settings > Devices > Displays and changed my scaling to 200% so I can actually read text. Then I performed some outstanding Ubuntu software updates and rebooted when prompted. When I logged back in, the scaling controls were no longer present in Settings > Devices > Displays, so now I'm stuck with tiny text and UI.

I suspect the cause of the missing scaling controls was the software update I performed to mutter 3.26.2-0ubuntu0.1, which the changelog says introduced a HiDPI-related patch for bug #1724024.

[Sébastien Taylor (sebastient)]

This is a serious bug introduced in a minor (automatic) patch. Any update on a fix?

[Sebastien Bacher (seb128)]

Could somebody open a new bug about the regression, that's a new issue and more important than the original problem here.

@jbicha, is that a problem known by you?

[Jeremy Bícha (jbicha)]

No, I've not seen that possible regression reported until today.

Please do file a separate bug for your recent issue. If it is a recent regression, it can't be the same issue as a bug reported in September.

https://wiki.ubuntu.com/StableReleaseUpdates#Regressions

[Marco Trevisan (Treviño) (3v1n0)]

That's definitely another issue...

However for the main one, could you please attach your ~/.config/monitors.xml just before and after changing the setting and also after a logout/login cycle?

[Sébastien Taylor (sebastient)]

Once the other bug is fixed I can do that. But right now I can't change
the scaling at all.

On 23 November 2017 at 18:57, Marco Trevisan (Treviño) <[e-mail]>
wrote:

> That's definitely another issue...
>
> However for the main one, could you please attach your
> ~/.config/monitors.xml just before and after changing the setting and
> also after a logout/login cycle?
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1720465
>
> Title:
> HiDPI scaling does not hold across reboot
>
> Status in gnome-shell package in Ubuntu:
> Confirmed
>
> Bug description:
> Running Ubuntu 17.10 Beta (updated as of 29 Sept 2017) on Parallels
> Desktop 13. When changing the HiDPI scaling to 200% everything looks
> good, but on restart the settings are reset to 100%.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+
> bug/1720465/+subscriptions
>

[John Wang (johnwang)]

I created a new 17.10 VM in Parallels 13 and didn't update any packages post-installation, so I can still access the scale controls in Settings.

I'm attaching copies of ~/.config/monitors.xml before changing any settings, immediately after changing Settings > Devices > Displays > Scale to 200%, and after rebooting (which yields identical results to simply logging out and back into a session).

Curiously, there are 2 Xorg servers running on a fresh installation, and this is true both before and after installing Parallels Tools in the guest VM:

---

user1@testvm1:~$ ps aux | grep -i xorg
root 1078 0.1 0.3 464924 15300 tty1 Sl+ 19:54 0:00 /usr/lib/xorg/Xorg vt1 -displayfd 3 -auth /run/user/121/gdm/Xauthority -background none -noreset -keeptty -verbose 3
root 1369 2.2 5.4 891936 220480 tty2 Sl+ 19:54 0:04 /usr/lib/xorg/Xorg vt2 -displayfd 3 -auth /run/user/1000/gdm/Xauthority -background none -noreset -keeptty -verbose 3

---

Also attaching a screenshot of Settings > Details > About, to show the string of the video driver installed by Parallels.

[John Wang (johnwang)]

I also noticed that the first monitors.xml I attached is version 1 of the file spec, while the monitors.xml files created after I changed the scale in Settings are version 2.

[Marco Trevisan (Treviño) (3v1n0)]

Is this still happening on 18.04?

I guess this could have been caused also by changing desktop (i.e. switching unity to gnome?).

[Daniel van Vugt (vanvugt)]

Removing Assigned to, so that the bug can expire.

[John Wang (johnwang)]

@3v1n0 I tried but can't yet confirm if the original reboot persistence bug is still happening, because it seems every time I test it an additional layer of problems occurs.

Parallels Desktop 13 still doesn't officially support Ubuntu 18.04. Ubuntu installs okay, but post-installation the VM guest tools (Parallels Tools) don't install due to breaking changes. Unfortunately those tools are necessary to enable the full host monitor resolution (2880x1800 in my case for my MacBook Pro) within the Ubuntu guest VM, and without the VM guest tools the Ubuntu VM is stuck with 800x600. The relevant Parallels support thread is here:

https://forum.parallels.com/threads/parallels-support-for-ubuntu-18-04-lts.344488/

In that thread this third party workaround was mentioned:

https://gist.github.com/rudolfratusinski/a4d9e3caff11a4d9d81d2e84abc9afbf

Luckily using that workaround I was able to get Parallels Tools installed successfully, but since that's not an official fix I'm not confident all of the tools are fully working. I rebooted the Ubuntu VM and it detected and enabled the full 2880x1880 resolution of my host machine, finally!

Then I opened Settings > Devices > Displays, but the HiDPI scaling controls are missing entirely. This is similar to what happened in the Ubuntu 17.10 guest VM in my comment #7 above, except this time the scaling controls are missing on a fresh installation of 18.04 without having yet performed any additional Ubuntu software updates. Even after installing all current Ubuntu updates and rebooting, the scaling controls are still missing.

Also perhaps worth mentioning is that under Parallels Desktop 13 the default Ubuntu 18.04 GNOME session continues to use the X.org backend instead of Wayland, just as under 17.10 (there are two instances of the X server running, one on vt1 serving the GNOME greeter, and one on vt2 serving the desktop session). I suspect this is due to Parallels' custom display driver, which identifies itself on my machine as "Parallels using AMD Radeon pro 555 opengl engine".

[Daniel van Vugt (vanvugt)]

Sébastien,

After you upgrade to 18.04, please run 'apport-collect 1720465' to provide us with newer system information.

[Sébastien Taylor (sebastient)]

apport information

[Sébastien Taylor (sebastient)]

apport information

[joreporter (joreporter)]

A 2017 issue still there in 2020... I have the same problem with Ubuntu 19.10

[Daniel van Vugt (vanvugt)]

I think this might have been fixed. Can anyone confirm?

[Launchpad Janitor (janitor)]

[Expired for gnome-shell (Ubuntu) because there has been no activity for 60 days.]