I'm not sure why there's such a long publisher delay with this one, but it still is not appearing to apt in questing-proposed on any of my machines. Regardless, I also completed step 6 by installing the deb from https://launchpad.net/ubuntu/+source/gnome-remote- desktop/49.0-0ubuntu1.1/+build/31444533/+files/gnome-remote- desktop_49.0-0ubuntu1.1_amd64.deb manually on my older generation nvidia machine (ASUS ROG Zephryus G15 with Nvidia RTX 3060 (Ampere).)
Based on Alessandro's point in https://bugs.launchpad.net/ubuntu/+source/gnome-remote- desktop/+bug/2127792/comments/5, I am going to change step 5 of the test plan from "Run the same test without a monitor plugged in to the DUT" to "Run the same test using software rendering, or with the monitor unplugged (which should have the same impact)", and switch the order (so that people can do it before chmod'ing the descriptor). This seems more precisely tuned to the real impact of that part of the test, and will allow for a less troublesome reproducer for those without physical hardware access. With that said, I think we can mark this verified as soon as it starts getting pulled from proposed via apt. (but let me know if we're good to do it now). ** 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 (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. + version supports NVENC, the .deb does not. - 4. Test gnome-remote-desktop with and without the fix. Make sure which + 4. On the server with a Blackwell GPU, test gnome-remote-desktop with + and without the fix using software rendering, or with the monitor + unplugged (which should have the same impact) + + 5. On the server with a Blackwell GPU, run `sudo chmod 666 + /dev/dri/renderD128` to enable GPU acceleration with RDP. + + 4. Run the same test, now with GPU acceleration enabled. 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) + 6. Run the same tests (with and without software rendering) 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. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2127792 Title: Images are corrupted on blackwell GPUs To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-remote-desktop/+bug/2127792/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
