[nouveau] Gnome shell/Xorg freeze after remote connection with monitor unplugged

[Pietro Smusi]

I was trying to have a remote connection on a Ubuntu 18.04 pc with nomachine (but the behavior with Anydesk is the same) AFTER I unplugged the monitor form that pc.
Once connected the output on the client freeze by just opening the Activities panel. If I plug the monitor back in on the server, the gnome shell is glitched and the only way to gain back control is by doing ALT F2 and then r.
If I keep the monitor plugged in but turned off everything will work as it should.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7.1
ProcVersionSignature: Ubuntu 5.0.0-29.31~18.04.1-generic 5.0.21
Uname: Linux 5.0.0-29-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Tue Sep 24 00:24:03 2019
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: I just need to know a workaround
GraphicsCard:
 NVIDIA Corporation GP107 [GeForce GTX 1050 Ti] [10de:1c82] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: ZOTAC International (MCO) Ltd. GP107 [GeForce GTX 1050 Ti] [19da:2454]
InstallationDate: Installed on 2019-07-16 (69 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
MachineType: Gigabyte Technology Co., Ltd. GA-78LMT-USB3 6.0
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.0.0-29-generic root=UUID=dfa66545-9ac3-41fa-817b-433d8a61bd78 ro quiet splash vt.handoff=1
SourcePackage: xorg
Symptom: display
Title: Xorg freeze
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/25/2014
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F2
dmi.board.name: GA-78LMT-USB3 6.0
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF2:bd11/25/2014:svnGigabyteTechnologyCo.,Ltd.:pnGA-78LMT-USB36.0:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-78LMT-USB36.0:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: GA-78LMT-USB3 6.0
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.97-1ubuntu1~18.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 19.0.8-0ubuntu0~18.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx 19.0.8-0ubuntu0~18.04.1
version.xserver-xorg-core: xserver-xorg-core N/A
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A
version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A

[Daniel van Vugt (vanvugt)]

It appears the freeze was due to a crash mentioned in your kernel:

[ 551.339814] gnome-shell[1798]: segfault at 4400 ip 00007f29b593b9e1 sp 00007ffe617a1710 error 4 in libmutter-2.so.0.0.0[7f29b58b0000+158000]
[ 551.339837] Code: 00 4c 89 e2 48 89 ee 48 89 df e8 fa 04 fc ff 85 c0 74 5e 4c 8b 74 24 18 e8 4c b0 01 00 4d 85 f6 74 df 49 8b 0e 48 85 c9 74 05 <48> 39 01 74 0f 48 89 c6 4c 89 f7 e8 4f 14 fc ff 85 c0 74 c3 41 f6

therefore...

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Launchpad Janitor (janitor)]

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

[Launchpad Janitor (janitor)]

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