Public bug reported:

GNOME Remote Login accepts an RDP connection and starts a headless GDM Wayland 
session. When Mutter selects
the NVIDIA GPU as the primary renderer, gnome-shell terminates with SIGSEGV and 
the RDP session is
disconnected.

The visible point of failure varies. In earlier reproductions, the client 
remained completely black and
disconnected before showing GDM. In a clean Apport reproduction with NVIDIA 
610.43.02, the GDM login
interface rendered successfully. After valid credentials were submitted, the 
display turned black and
disconnected.

The new crash report still identifies the crashing process as:

/usr/bin/gnome-shell --mode=gdm --no-x11

This suggests that the crash occurs in the remote GDM session during 
login/session handover, rather than in
an established user desktop.

The failure is reproducible with NVIDIA 610.43.02. The same machine can 
complete GNOME Remote Login
successfully when the headless session is forced to use Mesa on the AMD 
integrated GPU, while the NVIDIA
driver remains installed and active.

System information:

- Ubuntu 26.04, x86_64
- Kernel: 7.0.0-28-generic
- GNOME Shell: 50.1-0ubuntu1.1
- Mutter: 50.1-0ubuntu2.2
- GNOME Remote Desktop: based on 50.0-0ubuntu2
- NVIDIA driver: 610.43.02-0ubuntu0.26.04.1
- Driver package: nvidia-driver-610-open
- NVIDIA GPU: GeForce RTX 4070 Ti, PCI ID 10de:2782
- AMD integrated GPU: Raphael, PCI ID 1002:164e
- Client: Microsoft Remote Desktop (mstsc) on Windows

Steps to reproduce:

1. Enable Settings → System → Remote Desktop → Remote Login.
2. Ensure the headless GDM Wayland session selects the NVIDIA GPU as its 
primary renderer.
3. Connect to TCP port 3389 using Windows mstsc.
4. If the GDM login screen appears, submit valid local user credentials.
5. Observe the remote screen.

Actual result:

The client either remains black from connection time, or reaches GDM and turns 
black after credentials are
submitted. It is then disconnected.

Relevant server log:

gnome-shell: Running GNOME Shell (using mutter 50.1) as a Wayland display server
gnome-shell: No seat assigned, running headlessly
gnome-shell: Added device '/dev/dri/renderD128' (nvidia-drm) using no mode 
setting.
gnome-shell: Added device '/dev/dri/renderD129' (amdgpu) using no mode setting.
gnome-shell: Created gbm renderer for '/dev/dri/renderD128'
gnome-shell: Created gbm renderer for '/dev/dri/renderD129'
gnome-shell: Boot VGA GPU /dev/dri/renderD128 selected as primary
gnome-shell: Obtained a high priority EGL context
kernel: gnome-shell: segfault ... error 6 in memfd:/.glXXXXXX
systemd: [email protected]: Main process exited, code=dumped, 
status=11/SEGV

There are no NVIDIA Xid messages in the kernel log.

Expected result:

The GDM login screen and subsequent user desktop should render normally, and 
the RDP connection should
remain active when NVIDIA is selected as the primary renderer.

A/B comparison:

- NVIDIA GLVND/EGL selected: reproducible black screen followed by gnome-shell 
SIGSEGV.
- Mesa EGL forced for the headless session: Remote Login reaches the login 
screen and user desktop
successfully.
- Upgrading from NVIDIA 595 to NVIDIA 610.43.02 did not resolve the NVIDIA 
rendering path.

This appears similar to Launchpad bug #2062949, but this report concerns Ubuntu 
26.04, GNOME 50 and NVIDIA
610.43.02 on different hardware.

The installed GNOME Remote Desktop package contains a local fix for an 
independent libei input-event race.
That change does not affect Mutter renderer selection or EGL/GBM handling. The 
NVIDIA/Mesa A/B comparison
was performed using the same GNOME Remote Desktop binary.

** Affects: gnome-shell (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: multigpu nvidia resolute wayland

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https://bugs.launchpad.net/bugs/2162030

Title:
  GNOME Remote Login headless GDM shell crashes with NVIDIA 610

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