@Antoine I did need to `sudo chmod 666 /dev/dri/renderD128` to reproduce
this issue on Questing (since it's required to allow RDP to use the
GPU), just FYI. I'll update the test plan accordingly.

** Description changed:

  There is image distorsion in gnome-remote-desktop when a Blackwell GPU
  is in use and NVENC is responsible for the video streaming.
  
  Upstream issue: https://gitlab.gnome.org/GNOME/gnome-remote-
  desktop/-/issues/263
  
  A fix was just released by nvidia upstream, and also backported to GNOME 48: 
https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/merge_requests/344
  https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/merge_requests/346
  
  ---------------------------
  SRU Justification:
  
  [ Impact ]
  
   * This is a hardware enablement SRU.
  
   * gnome-remote-desktop, when used alongside NVENC for video streaming,
  simply does not work, because the image is broken.
  
   * With the above, the streaming is fixed.
  
  [ Fix ]
  
   * Nvidia devices never supported `NV_ENC_PARAMS_FRAME_FIELD_MODE_MBAFF`.
  Though the code worked for past, it causes interlaced line artifacts on
  Blackwell GPUs.
  
  * Using `NV_ENC_PARAMS_FRAME_FIELD_MODE_FRAME` and changing
  `grd-cuda-avc-utils` to produce progressive frames works on
  Blackwell and on older GPU generations.
  
  [ Test Plan ]
  
  1. Use a DUT that has a Blackwell GPU
  (https://en.wikipedia.org/wiki/Blackwell_(microarchitecture)#Blackwell_dies)
  
  2. Enable Remote Login from the Gnome Settings on the DUT with a monitor
  plugged in.
  
- 3. Install Reminna from Snap. This version supports NVENC, the .deb does
- not.
+ 3. Install Reminna from Snap (via the edge channel) on your client. This
+ version supports NVENC, the .deb does not. On the server, run `sudo
+ chmod 666 /dev/dri/renderD128` to enable GPU acceleration with RDP.
  
  4. Test gnome-remote-desktop with and without the fix. Make sure which
  backend is in use. This can be checked by running `nvidia-smi dmon` and
  observing an encoder activity >0%. The repro only occurs when the NVENC
  path is used. CPU encoding path or non-H264 streaming is unaffected
  
  5. Run the same test without a monitor plugged in to the DUT.
  
  6. Run the same tests (with and without monitors) on an older GPU
  generation (Maxwell, ideally)
  
  [ Where problems could occur ]
  
   * Given the nature of the fix, it should not impact non-nvidia machines.
   * Also, the  fix comes from nvidia themsleves, and it's in GNOME 48 and 49 
already, so it's pretty safe.

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https://bugs.launchpad.net/bugs/2127792

Title:
  Images are corrupted on blackwell GPUs

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